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                                                                   EXHIBIT 10.21






                            LEASE-PURCHASE AGREEMENT





                                     BETWEEN





                           MONTGOMERY COUNTY, MARYLAND



                                       AND



                             BIORELIANCE CORPORATION






                              Dated April ___, 1998
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                                TABLE OF CONTENTS

                                                                           Page

l.   INCORPORATION OF RECITALS................................................3

2.   GENERAL PURPOSES OF LEASE................................................3

3.   DEFINITIONS..............................................................4

4.   LEASED PREMISES..........................................................8

5.   TERM AND EXTENSION.......................................................8
     A.   Preliminary and Initial Terms.......................................8
     B.   Extension Terms.....................................................8
     C.   Right to Purchase...................................................9

6.   RENTAL..................................................................10
     A.   Amount.............................................................10
     B.   Rent Commencement Date.............................................11
     C.   Security Deposit...................................................11
     D.   Additional Rent....................................................12

7.   GUARANTY OF CONSTRUCTION................................................13

8.   FEES AND COSTS OF CONSTRUCTION..........................................13

9.   LESSEE'S INSURANCE......................................................14
     A.   Mandatory Insurance Requirements During the Construction Period....14
     B.   Mandatory Insurance Requirements During the Operations Period......15

10.  INDEMNIFICATION.........................................................18

11.  LIENS, CLAIMS OR ENCUMBRANCES...........................................19
     A.   Free of Liens......................................................19
     B.   Discharge of Lien..................................................20
     C.   Failure to Discharge Lien..........................................20

12.  RIGHT TO CONSTRUCT AND ARCHITECTURAL REVIEW.............................21
     A.   Submission and Approval of Plans...................................21
     B.   Plan Approval is not in Lieu of other Approvals/Permits............22
     C.   No Monetary Liability for Approval of Plans........................22
     D.   Coordination of Plans..............................................23
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                            TABLE OF CONTENTS
                               (CONTINUED)

                                                                           Page

13.  CONSTRAINTS.............................................................23
     A.   No Nuisance........................................................23
     B.   Notice of Toxic and Hazardous Materials............................23
     C.   Indemnification....................................................23
     D.   Outdoors Activities................................................24
     E.   Building Sites.....................................................24

14.  BUILDING CONSTRUCTION AND ALTERATIONS...................................24
     A.   Building Codes.....................................................24
     B.   Cleaning of Premises...............................................25
     C.   Premises "As Is"...................................................25

15.  LANDSCAPING, OUTSIDE STORAGE AND MAINTENANCE............................25
     A.   Landscaping........................................................25
     B.   Maintenance of Landscaping.........................................25
     C.   Screening of Storage Areas.........................................25
     D.   Storage of Fuel Oil, etc...........................................26
     E.   Safe Conditions....................................................26
     F.   Vacant Buildings...................................................26

16.  UTILITY CONNECTIONS.....................................................26

17.  SIGNS OR MONUMENTS......................................................27
     A.   Defined............................................................27
     B.   Approval of Plans..................................................27
     C.   Construction Signs.................................................27

18.  PARKING AREAS AND LOADING ZONES.........................................28
     A.   Parking Facilities.................................................28
     B.   Loading and Unloading Areas........................................28

19.  TEMPORARY STRUCTURES....................................................28

20.  MAINTENANCE OF PROPERTY.................................................29
     A.   Lessee's Obligation................................................29
     B.   County's Right, but not Obligation to Repair.......................29
     C.   County's Maintenance...............................................30
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                            TABLE OF CONTENTS
                               (CONTINUED)

                                                                           Page
21.  COOPERATIVE MAINTENANCE AGREEMENT AND COMMON AREA CHARGES...............30
     A.   Maintenance Agreement..............................................30
     B.   Common Area Contribution...........................................30
     C.   Storm Water Management.............................................31

22.  UTILITY SERVICE AND ACCESS..............................................31

23.  ACCESS BY COUNTY AND EASEMENT...........................................32
     A.   Access to Maintain Pipes...........................................32
     B.   Reservation of Easements...........................................32
     C.   Accommodation of Lessee............................................33

24.  COMMON AREAS............................................................33
     A.   Lessee's Non-exclusive Right to Use................................33
     B.   County's Right to Make Changes to Common Areas.....................33

25.  ENFORCEMENT.............................................................33
     A.   Lease for the Benefit of Parties...................................33
     B.   Remedies...........................................................33
     C.   Default............................................................34
     D.   No Subordination...................................................35
     E.   Bankruptcy.........................................................36

26.  EXPIRATION..............................................................36
     A.   Surrender of Improvements..........................................36
     B.   Removal of Trade Fixtures..........................................36

27.  TENANT HOLDING OVER.....................................................37

28.  MORTGAGE OF LESSEE'S LEASEHOLD INTEREST.................................37
     A.   Notice of Default under Mortgage or Lease..........................37
     B.   Leasehold Mortgagee Right to Notice and Cure.......................38
     C.   Leasehold Mortgagee as Holder of Lessee's Interest.................38
     D.   Certain Restrictions During Leasehold Mortgage.....................39
     E.   New Financing......................................................39
     F.   Assignment by Leasehold Mortgagee..................................39
     G.   Notice of Mortgages................................................40
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29.  SUCCESSORS AND ASSIGNS; SUBLEASING......................................40


                            TABLE OF CONTENTS
                               (CONTINUED)

                                                                           Page

30.  QUIET ENJOYMENT, TITLE TO LAND AND IMPROVEMENTS.........................43
     A.   Quiet Enjoyment....................................................43
     B.   Title..............................................................43

31.  SURRENDER, WAIVER AND AMENDMENT.........................................44

32.  NON-DISCRIMINATION IN EMPLOYMENT AND SERVICES...........................45

33.  DISPUTES................................................................45
     A.   Mediation of Disputes..............................................45
     B.   Exceptions.........................................................46

34.  CONTRACT SOLICITATION...................................................46

35.  PUBLIC EMPLOYMENT.......................................................47

36.  GOVERNING LAW, SEVERABILITY, CONDEMNATION AND COMPLIANCE................47
     A.   Governing Law......................................................47
     B.   Lease not Redeemable...............................................47
     C.   Casualty Damage....................................................47
     D.   Condemnation.......................................................48
     E.   Compliance with Law................................................49
     F.   No Waiver of Governmental Immunity.................................49
     G.   Limitation of Liability............................................49
     H.   Limitation of Lessee's Liability...................................49

37.  RECORDING...............................................................50

38.  ENTIRE AGREEMENT........................................................50

39.  NOTICE..................................................................50

40.  NON-MERGER..............................................................52

41.  SUBORDINATION OF LEASE..................................................52
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42.  CAPTIONS, PRONOUNS......................................................52

                            TABLE OF CONTENTS
                               (CONTINUED)

                                                                           Page

43.  SURVIVAL ...............................................................53

44.  MISCELLANEOUS PROVISIONS................................................53
     A.   Days...............................................................53
     B.   Certain Terms......................................................53
     C.   Authority..........................................................53
     D.   No Partnership.....................................................53
     E.   Consequential Damages..............................................53


     Exhibit A   -   Diagram of Leased Premises
     Exhibit B   -   Amended and Restated Declaration of Covenants and Easements
     Exhibit C   -   Development Plan and Development Criteria
     Exhibit D   -   Purchase and Sale Agreement
     Exhibit E   -   Rent/Purchase Price Schedule
     Exhibit F   -   Estoppel Certificate and Consent
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                                      LEASE

         THIS LEASE, made this ____ day of April, 1998, by and between
MONTGOMERY COUNTY, MARYLAND, a political subdivision of the State of Maryland,
hereinafter called "County" and BIORELIANCE CORPORATION, a Delaware corporation
with its principal offices located at 9900 Blackwell Road, Rockville, Maryland
20850, hereinafter called "Lessee."

                                   WITNESSETH:

                                    Recitals

         That for and in consideration of the financial conditions hereinafter
reserved and the covenants and conditions hereinafter contained, County leases
and demises unto Lessee and Lessee rents from County the Premises and
appurtenant rights described more particularly as Parcel N/Q and containing
approximately 8.4 acres as shown on Exhibit A attached hereto and made a part
hereof, all as shown on a plat entitled "Parcel 'N/Q', Shady Grove Life Sciences
Center", recorded among the Land Records of Montgomery County, Maryland, in Plat
Book 175, Plat 19636 (the "Property" or the "Premises") in the Shady Grove Life
Sciences Center located in Montgomery County, Maryland.

         Lessee agrees to exercise reasonable efforts to begin construction of a
biopharmaceutical manufacturing facility (the "Facility") consisting of
approximately 58,733 square feet (of which only approximately 30,000 square feet
will be built out initially) on the Property within twelve (12) months following
the Lease Commencement Date (as herein defined). All improvements on the
Property, including the Facility, shall be consistent with the Montgomery County
Zoning Ordinance, as amended from time to time, and the permitted uses set forth
herein and the Development Plan (as herein defined). Lessee's right to construct
improvements on the Property, including the right to construct additional
improvements as may be allowed by the Development
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Plan, as the Development Plan may be amended from time to time, shall not exceed
density of one hundred twenty thousand (120,000) square feet on the Property.
Lessee shall exercise reasonable and diligent efforts to: (i) file an
application for the building permit(s) for the Facility within six (6) months
after the Lease Commencement Date; and (ii) obtain a building permit(s) and
begin construction of the Facility within twelve (12) months after the Lease
Commencement Date. In the event Lessee fails to secure all necessary building
permit(s) for the Facility to be constructed on the Property within twelve (12)
months from the Lease Commencement Date, Lessee, at its option, may terminate
this Lease. In the event Lessee fails to (i) file an application for the
building permit(s) for the Facility within six (6) months after the Lease
Commencement Date or (ii) exercise reasonable and diligent efforts to obtain the
building permit(s) for the Facility within twelve (12) months after the Lease
Commencement Date, and either such failure continues beyond thirty (30) days
after written notice from County thereof, County, at its option, may terminate
this Lease, in which event Lessee shall, at its expense and at the option of
County, restore the Premises, to the extent practicable, to a safe condition in
compliance with all laws, ordinary wear and tear and casualty damage excepted.
Once construction of the Facility has begun, Lessee shall exercise reasonable
efforts to continue construction activities until completion.

         Now, therefore, for and in consideration of the terms of this Lease,
the parties agree as follows:


         1. INCORPORATION OF RECITALS. The recitals are incorporated herein as
if fully set forth.


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         2. GENERAL PURPOSES OF LEASE. County hereby declares and Lessee agrees
that the general purposes of this Lease are to:

                  A. Fulfill the purpose for which the land covered by the
Development Plan was secured, namely, for the development of the Life Sciences
Center.
                  B. Protect County, Lessee, and tenants against improper
building upon and use of the Property and Common Areas (as herein defined).

                  C. Guard against the erection on the Property or the Common
Areas of structures built of improper or unsuitable materials, or with improper
quality and methods of construction.

                  D. Provide setbacks from streets, property lines, and
easements, and in general provide adequately for a high type and quality of
improvement and for the orderly and efficient maintenance thereof.

                  E. Encourage development of the Shady Grove Life Sciences
Center:

                     (1) to enhance advancement in health delivery, education,
research, and development, and related, associated, or supporting entities and
promote an environment conducive to the advancement of health care and life
sciences technology and in general to provide a harmonious development.

                     (2) to develop strong relationships among facilities
within the Life Sciences Center so they can share the advantages of common
facilities in clinical, administrative, and support services that will result in
more efficient use of capital investment and manpower.


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                     (3)  to provide flexibility for change to accommodate
unforeseen knowledge, technology, and medical change, and advancement in
biomedical, life science, and medical device technology.

                     (4) to secure and maintain the desired functional
relationships within the Life Sciences Center for a cohesive development of
health care, research, and related medical uses.

         3. DEFINITIONS. When used in this Lease, the following terms have the
meanings set forth below:

            A. The "County" means Montgomery County, Maryland, as the owner and
lessor of the Property and grantor of use rights, and any reference in this
Lease to an approval, consent or agreement required to be obtained from County
refers to County in its capacity as the owner and lessor of the Property and
grantor of use rights and, unless otherwise indicated, does not refer to
approvals, consents or agreements required to be obtained from County in its
governmental capacity. County shall not unreasonably withhold, condition or
delay any approval, consent or agreement required under this Lease to be
obtained from County. County as the owner and lessor of the Property and grantor
of use rights shall, at Lessee's expense, cooperate with Lessee in filing any
application for zoning, land use and building permits and any other permits and
approvals necessary to the construction, development, use and operation of the
Property in a timely manner at the earliest possible date. County, in its
governmental capacity, agrees to act promptly in processing and reviewing
applications for all approvals and permits for the construction, development,
use and operation of the Property.


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            B. The "Covenants" means the Amended and Restated Declaration of
Covenants and Easements, dated March 9, 1990, and recorded among the Land
Records of Montgomery County, Maryland, in Liber 9332, folio 591. A copy of the
Covenants is attached hereto as Exhibit B. Lessee hereby acknowledges that it
has received and reviewed the Covenants.

            C. "Days" means calendar days, unless specific reference is made to
business days.

            D. The "Development Plan" means the Shady Grove Life Sciences Center
Development Plan approved by County, in its governmental capacity, on September
16, 1986, and the amendment dated February 10, 1994, to the Development Plan
which was approved by County, in its governmental capacity, on February 14,
1995, copies of which are attached hereto as Exhibit C, and any amendments to
the Development Plan which may be issued by County, in its governmental
capacity, from time to time.

            E. The "Facility" means the biopharmaceutical manufacturing facility
consisting of approximately 58,733 square feet (of which only approximately
30,000 square feet will be built out initially) to be constructed by Lessee on
the Premises, and such other and further improvements as may be allowed on the
Premises consistent with the Development Plan.

            F. "Improvements" means any structure, fixture or other improvements
now located or hereinafter erected upon the Premises, including, but in no way
limited to, the Facility and appurtenances to be constructed together with the
building, parking lots, landscaping, etc.


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            G. "Lease Commencement Date" means the effective date of this Lease,
which date is the first day of the month immediately following the date of final
ratification and execution of this Lease by County and Lessee.

            H. The "Lessee" means BioReliance Corporation, a Delaware
corporation, its successors and assigns. Lessee's interest in this Lease may be
assigned, and all or any portion of the Premises may be sublet, in accordance
with Section 29 hereof, provided that no such assignment or subletting shall be
deemed to release Lessee from its obligations under this Lease.

            I. "Mortgage" means any now or hereafter existing mortgages, deeds
of trust or other similar security agreements covering this Lease, or any
sublease or sub-sublease, and the term "Leasehold Mortgagee" means any mortgagee
or beneficiary under a deed of trust or other similar security agreement
covering this Lease, or any sublease or sub-sublease.

            J. "Occupant" includes any person or persons who, by reason of
employment or other status occupy space on or within the Premises and
Improvements.

            K. The "Plans and Specifications" means (i) the architectural and
structural plans entitled "Magenta Corporation, Shady Grove Life Sciences
Center, Rockville, Maryland," dated November 17, 1997, prepared by Gaudreau,
Inc. and Faisant Associates, Inc., and (ii) the specifications entitled "Project
Manual for Magenta Corporation, Shady Grove Life Sciences Center, Rockville,
Maryland," dated November 17, 1997, prepared by Gaudreau, Inc. and Faisant
Associates, Inc., as each of the same may be modified.

            L. The "Premises" and the "Property" mean that parcel of land more
particularly described as Parcel N/Q on Exhibit A and containing approximately
8.4 acres and shall include all Improvements constructed thereon.


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            M. "Property Value", for purposes of this Lease, means the
discounted value of the Property, in consideration of the economic development
benefits to be generated by the Facility to be constructed by Lessee, based upon
the acreage conveyed for use pursuant to this Lease. The Property Value is SEVEN
HUNDRED TWENTY THOUSAND DOLLARS ($720,000.00).

            N. "Shady Grove Life Sciences Center" and "Life Sciences Center"
mean the property and the improvements covered by the Development Plan which at
this time consists of approximately 295 acres bounded by Key West Avenue on the
north, Shady Grove Road on the east, Great Seneca Highway on the west and West
Montgomery Avenue on the south, and including an approximately 6.92 acre parcel
on the west side of Great Seneca Highway adjacent to the Public Service Training
Academy, all of which land is in Montgomery County, Maryland.

            O. The "Site Plan" means the "Storm Drain, Paving and Site Plan"
prepared by Loiederman Associates, Inc., dated August 1997, and amended October
17, 1997, October 22, 1997 and January 21, 1998, approved by the Shady Grove
Life Sciences Center Architectural Review Committee for development of the
Improvements, as the same may be amended.

         4. LEASED PREMISES.

            County hereby leases unto Lessee, for the consideration set forth
below, the Premises, initially for the construction, operation, and use of a
biopharmaceutical manufacturing facility in the Shady Grove Life Sciences
Center, and thereafter for any use permitted by the Covenants.


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         5. TERM AND EXTENSION.

            A. Preliminary and Initial Terms. The term of this Lease shall
consist of a Preliminary Term, an Initial Term and any Extension Terms exercised
by Lessee (collectively, the "Term"). The "Preliminary Term" of this Lease shall
commence on the Lease Commencement Date and expire on midnight of the day before
the Rent Commencement Date (as herein defined). The "Initial Term" of this Lease
shall be for a period of thirty-five (35) years commencing upon the Rent
Commencement Date and expiring, unless extended pursuant to the terms of this
Lease, on midnight of the last day of the thirty-fifth (35th) lease year. As
used herein, the term "lease year" means a twelve (12)-month period commencing
on the Rent Commencement Date or any anniversary thereof.

            B. Extension Terms. If this Lease has not been terminated sooner as
provided herein, then Lessee shall have the options (the "Extension Options") to
extend this Lease for two (2) additional and consecutive terms of twenty-five
(25) years each and one (1) additional consecutive term of fourteen (14) years
(each an "Extension Term" and, collectively, the "Extension Terms"). Should
Lessee, in Lessee' s sole discretion, elect not to extend this Lease, then
Lessee shall provide County with written notice of such election, together with
the written approval of any subtenant of Lessee, not later than one (1) year
before the date of expiration of the Term, failing which Lessee shall be deemed
to have exercised the Extension Option. For all purposes hereunder, there shall
be no distinction between the terms "extend" and "renew" and their derivatives.

            C. Right to Purchase. As additional consideration for the execution
of this Lease, County grants to Lessee an option to purchase the Premises at any
time during the Term


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(the "Purchase Option"), subject to the terms and conditions set forth herein
and substantially in the form of Purchase and Sale Agreement attached hereto as
Exhibit D and made a part hereof (the "Purchase Agreement"). Lessee may exercise
the Purchase Option by giving County written notice of such exercise, which
notice shall be accompanied by two (2) copies of the Purchase Agreement executed
by Lessee (the "Lessee's Notice"). County shall execute the Purchase Agreement
promptly after receipt of Lessee's Notice.

         The purchase price for the Premises shall be the unamortized balance of
the Property Value remaining as of the date of closing of said purchase based on
an equal monthly amortization of the Property Value at an interest rate equal to
the Interest Rate (as herein defined) over the period commencing on the Rent
Commencement Date and ending upon the expiration of the Initial Term. Such
amortization of the Property Value shall be computed within thirty (30) days
after determination of the Interest Rate, as set forth in Section 6.A., and
shall be set forth on a Schedule (the "Rent/Purchase Price Schedule") which
shall specify the exact amount of the monthly amortization, the portion of the
monthly amortization attributed to reduction of the Property Value, the portion
of the monthly amortization attributed to interest on the Property Value, and
the remaining unamortized balance of the Property Value for each month of the
Initial Term. The attached Exhibit E is a prototype of the Rent/Purchase Price
Schedule. The Rent/Purchase Price Schedule to be prepared after the Rent
Commencement Date shall be in substantially the same form as the prototype, and
shall be substituted for the attached Exhibit E. Notwithstanding the foregoing,
if Lessee and County close on the sale of the Premises pursuant to Lessee's
exercise of the Purchase Option prior to the Rent Commencement Date, the
purchase price for the Property shall be an amount equal to the original
Property Value, and if Lessee and


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County close on the sale of the Premises during an Extension Term, the purchase
price for the Property shall be Ten Dollars ($10.00).

         Failure by Lessee to pay the purchase price and close on the Premises
if and when obligated to do so under the Purchase Agreement shall be a default
under this Lease.

         6. RENTAL.

            A. Amount.

               (1) Initial Term. Subject to the terms and conditions of this
Lease, Lessee shall pay to County an annual base rent equal to twelve (12) times
that monthly amount required to amortize the Property Value over the period
commencing on the Rent Commencement Date and ending upon the expiration of the
Initial Term, at an interest rate (the "Interest Rate") equal to the lesser of
Seven Percent (7%) per annum or the 30-year U.S. Treasury Bond Rate as of the
Rent Commencement Date, which amount is payable in equal monthly installments,
in advance, without set off, deduction or demand, except as set forth in Section
36.D, on the first day of each month beginning on the Rent Commencement Date.
Any payment of annual base rent that is not made within fifteen (15) days after
the due date thereof is subject to a five percent (5%) late fee, which late fee
shall be waived by County twice each year.

                (2) Extension Terms. During each of the Extension Terms,
provided that Lessee has exercised the applicable Extension Option, Lessee shall
pay to County an annual base rent of One Dollar ($1.00), which amount is payable
in advance, without set off, deduction or demand, on the first day of each year.

            B.  Rent Commencement Date. The Rent Commencement Date shall be the
earlier to occur of: (a) the second anniversary of the Lease Commencement Date;
or (b) the date


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on which the applicable governmental authority issues the use and occupancy
certificate for the Facility. Lessee shall diligently pursue issuance of the use
and occupancy certificate for the Facility. In the event that the use and
occupancy certificate is issued before the second anniversary of the Lease
Commencement Date, and upon appeal is revoked before the second anniversary of
the Lease Commencement Date, all annual base rent shall be abated until the
earlier to occur of the second anniversary of the Lease Commencement Date, or
the issuance of a new use and occupancy certificate.

            C. Security Deposit. As of the Lease Commencement Date, Lessee shall
pay to County a security deposit in the amount of Ten Thousand Dollars
($10,000.00), which shall promptly be deposited in an interest-bearing account
by County. The security deposit, and all accrued interest thereon, shall be
applied against the first installment of base annual rent or returned to Lessee
upon earlier termination of this Lease, less any amounts properly withheld by
the County to restore the Premises, to the extent practicable, to a safe
condition in compliance with all laws, ordinary wear and tear and casualty
damage excepted.

            D. Additional Rent.

              (1) As additional rent hereunder, commencing on the Lease
Commencement Date, Lessee shall pay to the party entitled to receive the same
and discharge as they become due, promptly and before delinquency, all taxes,
assessments, rates, charges, license fees, municipal liens, levies, excises, or
imposts, whether general or special, or ordinary or extraordinary, of every
name, nature and kind whatsoever, including all governmental charges of
whatsoever name, nature, or kind, which may be levied, assessed, charged or
imposed, or which



                                       11
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may become a lien or charge on or against the leasehold estate of Lessee, or any
Improvements now or hereafter thereon which may be a subject of taxation, or on
or against County by reason of its ownership of the fee underlying this Lease,
during the Term, excepting income taxes and excess profits, estate, single
business, inheritance, succession, franchise or capital taxes upon County. If
Lessee shall desire to contest any tax, assessment or levy, Lessee may do so,
provided that, if required by law, Lessee shall pay any contested tax,
assessment or levy prior to the date upon which the same becomes due or shall
post bond or other security. The final judgment of a court of competent
jurisdiction that determines the validity and/or amount of any such assessment,
tax or levy shall be conclusive.

              (2) Specifically and without in any way limiting the generality of
the foregoing, Lessee shall pay all special assessments and levies or charges
made by any State, municipal or political subdivision for local improvements,
and shall pay the same in cash as they fall due and before they become
delinquent. Lessee must make these payments as they may be required by the act
and proceedings under which any assessments or levies or charges are made by any
State, municipal or political subdivision. If the right is given to pay any such
special assessment or levy either in one sum or in installments, then Lessee may
elect either payment method at its option. If Lessee elects to pay such special
assessment or levy in installments, Lessee shall be liable only for any
installment(s) payable prior to the expiration of the Term. All of the taxes and
charges under this Section shall be prorated among Lessee and County at the
commencement of the Term and expiration of the Term.


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              (3) All rebates on account of any such taxes, rates, levies,
charges, or assessments required to be paid and paid by Lessee under the
provisions hereof shall belong to Lessee.

              (4) Additional rent not paid by Lessee as due, and actually paid
by County after Lessee's continued failure to pay the same for fifteen (15) days
after receipt of written notice from County that such payment is overdue, is
subject to a five percent (5%) late fee.

         7. GUARANTY OF CONSTRUCTION.

            Lessee guarantees to County completion of and payment for the full
construction of the Facility in accordance with the Site Plan and the Plans and
Specifications.

         8. FEES AND COSTS OF CONSTRUCTION.

            Lessee shall pay all appropriate fees and charges imposed by utility
companies associated with the construction and operation of the Facility and
shall pay all costs of construction.

         9. LESSEE'S INSURANCE.

            A. Mandatory Insurance Requirements During the Construction Period:

              (1) During the period of time between the Lease Commencement Date
and the date on which the use and occupancy certificate is issued for the
Facility (the "Construction Period"), and thereafter whenever and for so long as
construction is resumed, Lessee shall obtain, at its own cost and expense, and
keep in force and effect the following



                                       13
<PAGE>   20
insurance coverages with an insurance company(ies) licensed to do business in
the State of Maryland. Lessee shall provide evidence of coverage by submitting a
certificate of insurance and/or certified copies of the insurance policies
within thirty (30) days after the Lease Commencement Date. Lessee's insurance
shall be primary.

                  (a) Commercial General Liability: Minimum Five Million Dollars
($5,000,000.00) combined single limit (which may be a combination of commercial
general liability and umbrella and/or excess liability policies) for bodily
injury and property damage coverage per occurrence including the following
coverages: Contractual Liability as afforded by Lessee's commercial general
liability policy; Premises and Operations; Independent Contractors; Products and
Completed Operations; Personal Injury; and Broad Form Property Damage.

                  (b) Worker's Compensation/Employer's Liability: Meeting all
requirements of Maryland law and with the following minimum limits: (1) Bodily
Injury by Accident - $100,000 each accident; (2) Bodily Injury by Disease -
$500,000 policy limits; and (3) Bodily Injury by Disease -$500,000 each
employee.

                  (c) Automobile Liability Coverage: Minimum One Million Dollars
($1,000,000.00) combined single limit for bodily injury and property damage
coverage per occurrence including the following: (1) owned automobiles; (2)
hired automobiles and (3) non-owned automobiles.

                  (d) Builder's All Risk Property Insurance: Lessee shall
provide a Builder's All Risk Property Policy including fire and extended
coverage to protect the interest of County, contractor and sub-contractors
against loss caused by the perils insured in the amount


                                       14
<PAGE>   21
of one hundred percent (100%) of the insurable value of the Facility. The
coverage must be written on a completed value form. The policy shall also
endorse a demolition and debris removal clause, extra expense and loss of use
coverages with a sub-limit of $500,000 per occurrence.

                  (e) Additional Insured: County shall be named as an additional
insured on all liability policies.

                  (f) Policy Cancellation: Forty-five (45) days prior written
notice must be provided to County of any cancellation, for other than
non-payment of premium, or material change of any of the policies.

                  (g) Certificate Holder: County, Department of Public Works and
Transportation, Division of Facilities & Services, 110 North Washington Street,
Rockville, Maryland 20850.

         B. Mandatory Insurance Requirements During the Operations Period:

            (1)   From and after the issuance of the use and occupancy
certificate for the Facility (the "Operations Period"), Lessee shall obtain, at
its own cost and expense, and keep in force and effect during the Term, the
following insurance coverages with an insurance company(ies) licensed to do
business in the State of Maryland. Lessee must provide evidence of coverage by
submitting a certificate of insurance and/or certified copies of the insurance
policies to County within thirty (30) days after the issuance of the use and
occupancy certificate. Lessee's insurance shall be primary.

                  (a) Commercial General Liability: Minimum Five Million Dollars
($5,000,000.00) combined single limit (which may be a combination of commercial



                                       15
<PAGE>   22
general liability and umbrella and/or excess liability policies) for bodily
injury and property damage coverage per occurrence including the following
coverages: Contractual Liability as afforded by Lessee's commercial general
liability policy; Premises and Operations; Independent Contractors; Fire Legal
Liability; and Personal Injury Coverage.

                  (b) Pollution Liability: If Lessee uses any radioactive
material or process at the Premises, it shall obtain, keep in force and effect,
and provide County with evidence of, a Pollution Liability policy with a minimum
limit of One Million Dollars ($1,000,000.00), to cover liability for discharge,
release or spills of radioactive material occurring as a result of Lessee's
operations on the Premises and the resulting clean-up costs for properties
adjoining the Premises. As an alternative to maintaining Pollution Liability
coverage, Lessee may provide County with a mutually acceptable letter of credit,
payable to County, to cover such exposure.

                  (c) Worker's Compensation/Employer's Liability: Meeting all
requirements of Maryland law and with the following minimum limits: (1) Bodily
Injury by Accident - $100,000 each accident; (2) Bodily Injury by Disease -
$500,000 policy limits; and (3) Bodily Injury by Disease - $500,000 each
employee.

                  (d) Automobile Liability Coverage: Minimum One Million Dollars
($1,000,000.00) combined single limit for bodily injury and property damage
coverage per occurrence including the following: (1) owned automobiles; (2)
hired automobiles and (3) non-owned automobiles.

                  (e) Property Insurance: Lessee shall provide property damage
insurance for the Facility.

                                       16
<PAGE>   23
                  (f) Pollution Clean-up: If Lessee uses any radioactive
material or process at the Premises, it shall obtain, keep in force and effect,
and provide County with evidence of, a Pollution Clean-up policy with a minimum
limit of One Million Dollars ($1,000,000.00), to cover, in the event of
discharge, release or spills of radioactive material occurring as a result of
Lessee's operations on the Premises, the costs of extracting such pollutants
from the Premises and restoring the Premises. As an alternative to maintaining
Pollution Liability coverage, Lessee may provide County with a mutually
acceptable letter of credit, payable to Lessor and County, to cover such
exposure.

               (2) Additional Insured: County shall be named as an additional
insured on all liability policies.

               (3) Policy Cancellation: Forty-five (45) days prior written
notice must be provided to County of any cancellation, for other than
non-payment of premium, or material change of any of the policies.

               (4) Certificate Holder: County, Department of Public Works and
Transportation, Division of Facilities & Services, 110 North Washington Street,
Rockville, Maryland 20850.

          C.   Lessee may carry any additional coverages required by any lender,
and any lender providing financing shall be named as loss payee under any
coverage required thereunder.

     10. INDEMNIFICATION.

          A.   Except as otherwise provided in this Lease, Lessee, as a material
part of the consideration for County's execution of this Lease, covenants with
County that Lessee shall


                                       17
<PAGE>   24
hold County harmless from and against any loss, damage, claim of damage,
liability or expense in connection with loss of life, personal injury and/or
damage to property (collectively, "Claims") arising from or out of an occurrence
upon or at the Premises, or the occupancy and use of the Premises or any part
thereof, or occasioned wholly or in part by any act or omission in or related to
the Life Sciences Center of Lessee, its employees, agents, contractors, tenants,
licensees or invitees, excepting Claims arising out of the acts or omissions of
County, County's agents, County's employees, County's contractors, County's
licensees or County's invitees. In case County shall, without fault on its part,
be made party to any litigation commenced by or against Lessee, Lessee shall
hold County harmless and shall pay all costs, expenses and reasonable attorneys'
fees incurred or paid in connection with such litigation. In no event shall the
limits of any insurance policy provided for herein be deemed to limit Lessee's
liability to County as herein set forth.

          B. Subject to the provisions of Sections 36.F (No Waiver of
Governmental Immunity) and 36.G (Limitation of Liability) of this Lease, County,
as a material part of the consideration for Lessee's execution of this Lease,
covenants with Lessee that County shall hold Lessee harmless from and against
any Claims occasioned wholly or in part by any act or omission in or related to
the Life Sciences Center of County, its employees, agents, contractors or
invitees, excepting Claims arising out of the acts or omissions of Lessee,
Lessee's agents, Lessee's employees, Lessee's contractors, Lessee's tenants,
Lessee's licensees or Lessee's invitees. In case Lessee shall, without fault on
its part, be made party to any litigation commenced by or against County, County
shall hold Lessee harmless and shall pay all costs, expenses and reasonable
attorneys' fees incurred or paid in connection with such litigation. The duty to



                                       18
<PAGE>   25
indemnify, defend and hold harmless Lessee does not extend to actions of County
in its governmental capacity which permits it to enter the Premises to conduct
inspections and to administer or enforce State and County laws, regulations and
ordinances.

          11. LIENS, CLAIMS OR ENCUMBRANCES.

              A. Free of Liens. Lessee shall at all times keep the Premises
free and clear of mechanics', materialmen's and other monetary liens caused or
created by Lessee or anyone claiming through or under Lessee, other than the
lien, operation, and effect of such Mortgages as may be necessary from time to
time to effectuate the financing of the Improvements, provided, however, that
the lien, operation, and effect of such Mortgages are subordinate to the lien,
operation, and effect of this Lease. Except with respect to the Purchase Option,
in no event will Lessee or any Leasehold Mortgagee have any rights to acquire
County's fee, nor will any Mortgage encumber County's interest in the fee.

              B. Discharge of Lien. If any mechanics', materialmen's or other
monetary lien shall at any time be filed against the Premises for work performed
by or for Lessee, Lessee shall either cause the same to be discharged of record
within thirty (30) days after Lessee's receipt of notice of the filing of the
same or, if Lessee shall desire to contest any such lien, Lessee shall, within
thirty (30) days after the date of the filing of the lien, furnish to County
security in one hundred fifty percent (150%) of the amount of the claim, or
shall procure a bond in said amount from a reputable bonding company. The final
judgment of any court of competent jurisdiction determining the validity and/or
amount of any such lien shall be conclusive.

                                       19
<PAGE>   26
              C. Failure to Discharge Lien. If Lessee shall fail to discharge
any monetary lien not permitted by this Lease or to provide County with security
therefor or procure a bond therefor as hereinabove provided, then County may at
its option, pay or discharge any such monetary lien, and Lessee shall pay County
all amounts spent by County, including costs, expenses and reasonable attorneys'
fees, incurred by County together with interest at the rate provided in
Section 11-107(a) of the Courts and Judicial Proceedings Article, Annotated Code
of Maryland, as amended, or in the event that such Section is repealed and not
re-enacted, then interest shall be at the prime rate set by Citibank of New York
or its successor, plus one percent (1%), which payment shall constitute
additional rent due hereunder and shall be paid within thirty (30) days after
County provides a reasonably detailed written notice of the additional rent to
Lessee. Nothing herein requires County to pay or discharge any lien. County may
exercise the remedies available in Section 25 of this Lease if the lien is not
paid, discharged or secured as required by this Lease.

          12. RIGHT TO CONSTRUCT AND ARCHITECTURAL REVIEW.

              A. Submission and Approval of Plans. County grants Lessee the
right to construct a building or buildings on the Premises in accordance with
the Development Plan and the Covenants (as determined by County) and subject to
the following conditions. No building, exterior improvement or addition, or
landscaping shall be erected, placed or altered until plans therefor have been
approved by County. Plans will be reviewed promptly when submitted, and approved
or disapproved within ten (10) business days of submission. If County shall fail
to respond to Lessee's request for approval of plans within such ten (10)
business day period, and shall fail to respond to Lessee's second request for
approval of such plans within five (5) business


                                       20
<PAGE>   27
days of such second request, then such plans shall be deemed approved by County.
Any disapproval shall be accompanied by a statement explaining the reasons for
the disapproval. If any plans are disapproved, Lessee shall promptly resubmit
revised plans. To the extent permitted by Section 10-617 of the State Government
Article, Annotated Code of Maryland, County shall keep confidential those plans
and related information submitted by Lessee which have been marked specifically
by Lessee as confidential. Lessee shall provide the following information to
County in four copies for its review and approval prior to (or, where
appropriate, approval, during) construction:

                     (1) All of the plans, specifications and other information
required by Paragraph II.F.3 of the Development Criteria attached to the
Development Plan as Appendix A; and

                     (2) All of the plans, specifications and other information
required by Paragraph II.B.1 of the Covenants.


                  B. Plan Approval is not in Lieu of other Approvals/Permits.
The architectural review and approval described in this Section does not alter,
replace, or in any way substitute for or constitute approval in lieu of other
permits, approvals or authorizations required in the normal building or
construction process.

                  C. No Monetary Liability for Approval of Plans. Neither County
nor any employee or agent thereof shall be liable for monetary damages to any
occupant or lessee or to anyone submitting plans or requests for approval, or to
any other party by reason of mistake in judgment, negligence, or nonfeasance,
arising out of or in connection with the approval, disapproval or failure to
approve any such plans or requests or for any other action in connection


                                       21
<PAGE>   28
with its or their duties hereunder. Likewise, anyone so submitting plans to
County for approval, by submitting such plans or requests, and any person when
he becomes an occupant or lessee, agrees that he or it will not bring any action
or suit to recover any monetary damages against County or any employee or agent
of County for such approval or disapproval. Any approval of plans by County
shall not constitute a representation by County that such approved drawings
comply with applicable building codes. Any deficiency in design or construction,
although same had prior approval of County, shall be solely the responsibility
of Lessee. Notwithstanding anything to the contrary in this Lease, the terms of
the foregoing paragraph shall apply to County solely in its capacity as owner
and lessor of the Property and grantor of use rights, and not in its
governmental capacity. The foregoing sentence shall not be construed as a waiver
of any defenses, including immunity, available to the County in its governmental
capacity.

                  D. Coordination of Plans. Any amendments, supplements or
additions to the approved plans, specifications and construction schedules for
all Life Sciences Center construction (including but not limited to roads and
utilities, but excluding interior alterations) shall be provided to and
coordinated with representatives of County and Lessee's architect (or the
architect of Lessee's subtenant or sub-subtenant), and must be reviewed by the
Architectural Review Committee of the Life Sciences Center and approved by
County.

              13. CONSTRAINTS.

              During the Operations Period, Lessee's use of the Premises is
subject to the following permitted uses and performance standards:

                  A. No Nuisance. No activity shall be conducted nor shall
anything be done on the Premises which may be or become a material nuisance to
County, general public, or any


                                       22
<PAGE>   29
lessee by reason of unsightliness or the excessive emission of fumes, odors,
glare, vibration, gasses, radiation, dust, waste, smoke or noise.

                  B. Notice of Toxic and Hazardous Materials. Lessee shall
provide County with a copy of: (a) each notification or other document it is
required to submit to the State Emergency Response Commission under Sections 311
and 312 of the Superfund Amendments and Reauthorization Act of 1986 and any
amendments thereto; and (b) each annual report it is required to submit to the
Maryland Department of the Environment under COMAR 26.13.03.06 and any
amendments thereto. Lessee shall store, manage, and dispose of all toxic,
hazardous and radioactive materials in accordance with applicable laws and
regulations.

                  C. Indemnification. During the Term, Lessee hereby agrees to
indemnify and hold County harmless, except in the case of the negligence or
intentional misconduct of County or its agents, employees, or contractors, with
regard to any Claims arising from or out of a breach of Lessee's obligations
under Section 13.B concerning toxic and hazardous materials, radioactive
materials, controlled substances and medical waste, including but not limited
to, reasonable counsel fees, court costs, litigation related expenses, expenses
for legally required clean up, enforcement expenses, and consequential damages
to the Premises and/or the remaining portion of the Shady Grove Life Sciences
Center resulting from the use or storage of the referenced materials on the
Premises.

                  D. Outdoors Activities. All of the operations normally carried
on indoors shall be carried on within fully enclosed buildings. No outside
activities shall be carried on, except for incidental meetings or events held
outside in non-inclement weather and the parking of motor vehicles and the
loading and unloading of motor vehicles and approved recreational


                                       23
<PAGE>   30
activities, without the prior approval of County. This paragraph shall not be
deemed to prohibit therapy and types of exercise normally carried on outdoors.

                  E. Building Sites. Building sites shall be used only as
approved by County in granting this Lease and approved by County through its
Development Plan and its architectural review, and in accordance with applicable
law.

              14. BUILDING CONSTRUCTION AND ALTERATIONS.

                  A. Building Codes. Lessee agrees that construction or
alterations of any building shall be in conformance with the then existing
applicable standards, codes and ordinances.

                  B. Cleaning of Premises. During the Construction Period,
Lessee agrees that all building sites shall be kept clean on a daily basis and
all trash, rubbish and debris removed therefrom after any construction work is
performed thereon.

                  C. Premises "As Is". Lessee has leased the Premises in an "as
is" condition after an examination thereof and of the sub-surface conditions
beneath the same and without any representation or warranty on the part of
County.

              15. LANDSCAPING. OUTSIDE STORAGE AND MAINTENANCE. Lessee agrees
that it will adhere to the following requirements.

                  A. Landscaping. Landscaping shall be in accordance with the
plan submitted to and approved in writing by County in accordance with Section
12.A.. Such landscaping shall include sodding, planting of trees, shrubs, and
other customary landscaping treatment for the entire Premises, including
adequate screening of parking areas. The approved plan for



                                       24
<PAGE>   31
landscaping may not be materially altered without submitting the revised plan
for written approval of County.

                  B. Maintenance of Landscaping. Maintenance of existing and
approved landscaping shall include keeping the lawns mowed and the hedges
trimmed, and the watering and removal of weeds from planted areas, all as needed
to maintain the Premises in a neat, clean and safe condition and appearance, as
is customary for other parcels within the Shady Grove Life Sciences Center.

                  C. Screening of Storage Areas. Except during construction, no
materials, supplies, equipment, vehicles (except in designated areas), finished
products or semi-finished products, furniture, furnishings, raw materials, or
other articles of any nature shall be stored or permitted to remain on the
exterior of any building site without appropriate screening to be approved by
County.

                  D. Storage of Fuel Oil, etc. Except during construction, or as
approved by County, permanent storage facilities for fuel oil, other bulk fluids
or gasses, such as bulk oxygen systems, must be provided below grade. If below
grade storage is technically infeasible or economically prohibitive, Lessee may
store these materials above grade provided suitable screening is furnished by
Lessee and approved by County. At all times, such materials must be stored in an
environmentally safe manner, pursuant to applicable Federal, State and local
laws and regulations.

                  E. Safe conditions. Lessee shall keep the Premises,
Improvements, and appurtenances in a safe, clean and neat condition, and shall
comply in all respects with all government health and policy requirements.
Lessee shall remove at its own expense any rubbish,


                                       25
<PAGE>   32
garbage or trash of any character which may accumulate from or on the Premises.
Rubbish, trash and garbage shall be kept in a sanitary manner inside buildings.

                  F. Vacant Buildings. Vacant or unfinished buildings, or parts
thereof, shall be adequately secured against vandalism and intrusion by
trespassers.

              16. UTILITY CONNECTIONS.

                  Lessee agrees that, except for emergency electricity
generators and satellite receiving transmission dishes, all electrical and
telephone connections and installations of wires to buildings shall be made
underground to the extent reasonably possible. Where reasonably possible each
transformer, electric, gas or other meter of any type, or other apparatus, shall
be placed on or below the surface of the land, or in structures, and where
placed on the surface shall be adequately screened and fenced, and all such
installations shall be subject to the prior written approval of County.
Notwithstanding the foregoing, County agrees that Lessee may place exhaust fans,
duct work, package HVAC units, satellite dishes and other equipment on the
screened area of the roof of the Facility. Lessee shall pay the costs of all
necessary utility connections.

              17. SIGNS OR MONUMENTS.

                  A. Defined. For the purpose of this paragraph, a sign or
monument is the display of any words, numerals, figures, devices, designs or
trademarks by which anything is made known and visible to the general public.

                  B. Approval of Plans. Lessee agrees that all plans and
specifications for signs or monuments to be erected on the exterior of the
building or grounds and visible to the general public shall be subject to the
prior written approval of County. The submitted


                                       26
<PAGE>   33
information shall include details of design, materials, location, color and
lighting, if any. Lessee may, subject to prior written approval of County, place
appropriate markers and directional signs on County's property outside of the
Premises, which shall be in keeping with the character and nature of Lessee's
operations.

                  C. Construction Signs. During any construction or
reconstruction of improvements on the Premises, County agrees to allow any
lender, contractor, developer or other participant in such construction or
reconstruction to place a temporary sign publicizing its participation in the
financing, construction or reconstruction of the Facility, subject to such
reasonable requirements as may be imposed by County, and subject to applicable
ordinances.

              18. PARKING AREAS AND LOADING ZONES.

                  A. Parking Facilities. Lessee shall provide adequate paved
off-street surface parking facilities for visitors, tenants, customers, and
employees as required by zoning regulations unless otherwise legally waived by
the proper authority. The development of common or jointly shared parking
facilities is encouraged and should be undertaken whenever possible. No parking
shall be permitted on any access road, street or driveway, either public or
private, or any place other than a paved parking space provided for and so
designated. Lessee shall be responsible for taking reasonable measures to ensure
compliance with parking regulations by its employees, tenants and visitors.

                  B. Loading and Unloading Areas. Lessee agrees that loading and
unloading areas shall be designed with adequate maneuvering space to permit
pickups and deliveries. The space for maneuvering of vehicles shall avoid
interference with other traffic flow. Suitable


                                       27
<PAGE>   34
screening shall be provided so these operations are not readily visible from
ground-level public thoroughfares. Loading and receiving areas shall not be
located on that side of the building which also contains its main entrance.

              19. TEMPORARY STRUCTURES.

                  Lessee agrees that no structure, covering, garage, barn, or
other outbuilding of a temporary nature shall be situated, erected or maintained
on any part of the Premises except with prior approval of County and in
compliance with applicable zoning ordinances. This paragraph shall not apply to
construction buildings, construction trailers, storage facilities and/or other
structures of a temporary nature used in construction, used during the course of
construction of any permanent building which is now on or is to be located on
the Premises; provided, however, that any such buildings, trailers, facilities
or other structures shall be in compliance with any applicable zoning
ordinances.

                  County hereby approves Lessee's installation and use of
temporary facilities on the Premises, subject to applicable zoning ordinances
and receipt of any necessary governmental approvals, and provided that any such
temporary facility shall be kept on the Premises only for the period, not to
exceed two (2) years, during which Lessee is constructing or building out space
on the Premises into which the business conducted in such temporary facility
will be moved.

              20. MAINTENANCE OF PROPERTY.

                  A. Lessee's Obligation. Lessee shall at all times maintain and
repair the Premises at Lessee's expense. Lessee must submit, for approval by
County, all maintenance and repair plans and amendments thereto for maintenance
and repairs to building exteriors, landscaping, fences, drives, parking lots,
and the exteriors of other structures located thereon,



                                       28
<PAGE>   35
which maintenance or repairs materially alter the condition of the Premises
which existed prior to the need for such maintenance or repair arising.

                  B. County's Right, but not Obligation to Repair. In the event
of the violation of any of the restrictions set forth in Sections 13 through 20
herein by Lessee, County shall notify Lessee in writing, giving specifics as to
the nature of the alleged violation and any recommended remedial action. In the
event Lessee has not taken steps to remedy the violation in a manner reasonably
acceptable to County within thirty (30) days after Lessee's receipt of such
notice, County shall have the right to enter upon the Premises to put the same
in good order, condition and repair and all costs associated with any such work
shall be charged against Lessee as additional rent payable within thirty (30)
days after invoice, which shall include reasonable details of the costs charged
as additional rent.

                  C. County's Maintenance. Subject to appropriation of funding,
County shall maintain in good order and condition all parcels within the Shady
Grove Life Sciences Center that have not been leased or that are unoccupied.
County further agrees to be responsible for making all necessary arrangements
for the maintenance and repair of the Common Areas (as defined in Section 24.A).
This provision shall survive the exercise of the Purchase Option and the
conveyance of the Premises to Lessee.

              21. COOPERATIVE MAINTENANCE AGREEMENT AND COMMON AREA CHARGES.

                  A. Maintenance Agreement. A maintenance agreement between
County and Lessee or among lessees of the Shady Grove Life Sciences Center may
be established for the purpose of maintaining the Common Areas. No such
agreement shall discharge or relieve Lessee


                                       29
<PAGE>   36
of its responsibilities under the terms and conditions of this Lease. All such
maintenance agreements shall be subject to the approval of County.

                  B. Common Area Contribution. Within thirty (30) days after
receipt of a reasonably itemized invoice, for each year during the Term, Lessee
agrees to pay as additional rent to County, Lessee's pro rata share, for the
purpose of reimbursing County for the actual costs of its care and maintenance
of the Common Areas within the Shady Grove Life Sciences Center that do not form
a part of the Premises. Such costs shall not include the costs of constructing,
replacing, or installing roads, parking areas, utilities, or related
infrastructure (e.g. the power plant) located within the Shady Grove Life
Sciences Center. Lessee's pro rata share shall be a fraction, the numerator of
which is 8.4 acres and the denominator of which is 220 acres. Based upon this
formula, Lessee's pro rata share, expressed as a percentage, is 3.82%. County
represents and warrants to Lessee that all of the occupants of the Shady Grove
Life Sciences Center, except Shady Grove Adventist Hospital (Parcel 1A),
Ambulatory Care I (Parcel 2A), Ambulatory Care II (Parcel 2B), Charter
Behavioral Health System of Maryland at Potomac Ridge, LLC (Parcels 3A and 3B),
and University of Maryland Systems, are required to pay for Common Area
maintenance and care as described in this Section 21.B.

                  C. Storm Water Management. Lessee will provide for the safe
conveyance of storm water from the Premises in accordance with County's rules
and regulations regarding storm water management.

              22. UTILITY SERVICE AND ACCESS.

                  A. County has provided for water, sewer, gas, electricity, and
telephone service to the Premises. All meters, connecting charges and all
outlets, risers, wiring, piping,


                                       30
<PAGE>   37
duct work or other means of distribution of such services within the Premises of
Lessee shall be supplied by Lessee at Lessee's expense. Lessee covenants and
agrees that at all times its use of any of such services shall never exceed the
capacity of the mains, feeders, ducts and conduits bringing same to the Premises
or of the outlets, risers, wiring, piping, duct work or other means of
distribution of such service within the Premises if such means of distribution
shall have been installed by County. Lessee may increase the capacity of the
mains, feeders, ducts, and conduits if Lessee pays for and performs all
necessary work therefor, and has obtained County's approval in writing. Such
work performed by Lessee shall be at no increased expense or cost to County in
any manner whatsoever. Other than the matters provided above, Lessee shall
furnish and pay for installation and use of all utilities, including but not
limited to fuel, gas, electricity, water, sewer charges, telephone and the
necessary equipment therefor within the Premises. Lessee shall construct, at its
own expense, the water and sanitary sewer lines to connect the Improvements.

              23. ACCESS BY COUNTY AND EASEMENT.

                  A. Access to Maintain Pipes. In the event Lessee fails to do
so within thirty (30) days after written notice from County, Lessee shall permit
County, at Lessee's expense, and subject to the provisions of this paragraph, to
repair and maintain all pipes and conduits in and through the Premises that
Lessee is required to maintain. County or its agent shall have the right to
enter upon the Premises at all reasonable times and upon at least forty-eight
(48) hours' notice except in case of an emergency to examine same and to make
such repairs, alterations, improvements or additions to same as may be required
of County pursuant hereto, and County shall be allowed to take all material into
and upon said Premises that may be required therefor



                                       31
<PAGE>   38
without the same constituting an eviction of Lessee, in whole or in part. In
case of an emergency, County shall give such notice to Lessee as is reasonable
under the circumstances.

                  B. Reservation of Easements. County reserves the right,
consistent with the Development Plan, Covenants and with the Plans and
Specifications, to establish easements and/or rights-of-way, for streets, roads,
underground utilities, and other related purposes, in order to facilitate
development of the Life Science Center. Such easements or rights-of-way shall
not interfere with the use, operations, or maintenance of, or materially
adversely affect the value of, the Property.

                  C. Accommodation of Lessee. County shall use reasonable
efforts to minimize the interference with business activities on the Premises
when exercising County's rights pursuant to this Section.

              24. COMMON AREAS.

                  A. Lessee's Non-exclusive Right to Use. County hereby grants
to Lessee a non-exclusive right to use: (i) the public conveniences and common
areas, if any, in the Life Sciences Center; and (ii) all other areas in the Life
Sciences Center such as sidewalks, roads and driveways, to be used in common by
lessees of the Life Sciences Center, ((i) and (ii) collectively referred to and
identified for use as "Common Areas").

                  B. County's Right to Make Changes to Common Areas. County
reserves the right to construct buildings and to make changes, additions,
alterations or improvements on or to the Common Areas; provided, however, that
such activity does not cause an obstruction of the access to the Premises, any
unreasonable interference with the permitted uses of the Premises, or a material
adverse effect on the value of the Premises.

                                       32
<PAGE>   39
              25. ENFORCEMENT.

                  A. Lease for the Benefit of Parties. The provisions of this
Lease shall run for the Term of this Lease (including any Extension Terms) and
be binding upon and inure to the benefit of County and Lessee and Lessee's
successors and assigns. These provisions shall be enforced, as provided
hereinafter, by County or by Lessee for their respective benefit or protection.

                B. Remedies. A violation of any provision herein contained
shall give to County or Lessee the right to bring proceedings in a court of
competent jurisdiction against the party or parties violating or attempting to
violate any of said covenants, conditions, restrictions and reservations, to
enjoin them from so doing, to cause any violation to be remedied, and/or to
recover damages resulting from such violation. In addition, violation of any
covenants, conditions, restrictions, and reservations shall give to County the
right to enter upon the Premises to remove, at the expense of Lessee, any
structure, thing or condition that may be contrary to the provisions hereof
after providing Lessee's subtenant and sub-subtenant and any Leasehold
Mortgagee, if any, with written notice of the violation and providing not less
than thirty (30) days in which to cure the alleged violation, which cure period
shall be extended for so long as may be reasonably necessary to cure such
violation, so long as Lessee, Lessee's subtenant or sub-subtenant or any
Leasehold Mortgagee proceeds diligently to effect such cure after receipt of
County's notice. In any judicial proceeding to enforce the provisions hereof or
to enjoin their violation, the prevailing party or parties shall be entitled to
reasonable attorneys' fees from the party or parties against whom judgment is
entered in such amount as may be fixed by the court in such proceedings. Such
remedies shall be cumulative and not exclusive.


                                       33
<PAGE>   40
                  C. Default. Lessee's violation of any of the provisions of
Section 6 requiring Lessee to pay annual base rent and additional rent, Section
7 requiring Lessee to complete and pay for the full construction of the
Facility, or Section 9 requiring Lessee to maintain and provide County with
evidence of the insurance coverages set forth therein, or Lessee's use of the
Premises for any use other than those permitted by the Covenants, shall, at
County's option, be deemed to create a default under this Lease and to give rise
to the right of termination or eviction, or any other remedy provided by law,
provided that said violation has not been cured within thirty (30) days after
written notice has been given to Lessee, Lessee's subtenant and sub-subtenant
and any Leasehold Mortgagee, and further provided that Lessee, Lessee's
subtenant or sub-subtenant or any Leasehold Mortgagee has not taken steps to
remedy said violation in a manner reasonably acceptable to County within said
thirty (30) days after the written notice or has not thereafter diligently
proceeded to complete the remedying of such violation, and further provided that
Lessee's subtenant or sub-subtenant has not cured such violation within a
reasonable time after receipt of the second default notice described in Section
29. Lessee's material violation of any of the other provisions set forth herein
shall, at County's option, be deemed to create a default under this Lease but
shall not in any event give rise to the right of termination or eviction;
provided, however, that such default shall give rise to any other remedy
provided by law, provided that said violation has not been cured within thirty
(30) days after written notice has been given to Lessee, Lessee's subtenant and
sub-subtenant and any Leasehold Mortgagee, and further provided that Lessee,
Lessee's subtenant or sub-subtenant or any Leasehold Mortgagee has not taken
steps to remedy said violation in a manner reasonably acceptable to County
within said thirty (30) days after the written notice or has not thereafter



                                       34
<PAGE>   41
diligently proceeded to complete the remedying of such violation, and further
provided that Lessee's subtenant or sub-subtenant has not cured such violation
within a reasonable time after receipt of the second default notice described in
Section 29.

                  D. No Subordination. Notwithstanding any other provision
herein, the parties hereto agree that this Lease shall not be subordinated to
the terms of financing or the financing entity or to any other instrument,
individual or entity.

                  E. Bankruptcy. Lessee agrees that it shall be a default of
this Lease if Lessee is (i) voluntarily placed into bankruptcy for purposes of
liquidation or (ii) involuntarily placed into bankruptcy for purposes of
liquidation and such bankruptcy proceeding is not dismissed within one hundred
fifty (150) days. In the event that Lessee is placed into bankruptcy for the
purpose of reorganization or rehabilitation, County and Lessee agree that it
shall be a default of this Lease only if such bankruptcy proceeding reduces the
amount of rent to be paid by Lessee; or Lessee has failed to pay the rent in
accordance with Section 6 of this Lease. Upon default of this Lease, County and
Lessee retain their respective remedies and cure rights set forth in this Lease.

              26. EXPIRATION.

                  A. Surrender of Improvements. At the expiration or earlier
termination of the Term, all buildings, alterations, additions or improvements
then upon the Premises shall become the property of County and remain upon and
be surrendered with the Premises as a part thereof.

                  B. Removal of Trade Fixtures. All trade fixtures, furnishings
and equipment, whether or not they are or may be deemed to constitute part of
the Improvements may be removed by Lessee, at its sole option. Lessee, at its
expense, shall immediately repair any



                                       35
<PAGE>   42
damage to the Premises or Improvements by reason of removal of any such trade
fixture, furnishings and equipment. If County elects to enter thereon and take
possession at the termination of this Lease, all repairs not previously made, at
the option of County, may be corrected at the expense of Lessee, normal wear and
tear excepted.

              27. TENANT HOLDING OVER.

                  If Lessee shall not immediately surrender possession of the
Premises at the expiration or termination of this Lease, County shall be
entitled to retake or recover possession of the Premises as hereinbefore
provided in case of expiration or termination on the part of Lessee and have
available to it any and all other remedies available by law. If Lessee shall
fail to surrender possession of the Premises immediately upon the expiration of
the Term, Lessee hereby agrees that all the rights and obligations of Lessee and
County applicable during the Term shall be equally applicable during such period
of subsequent occupancy, except that Lessee shall pay fair market rental during
the holdover tenancy. The determination of the fair market rental shall be
determined by an independent appraisal by an appraiser who is selected jointly
by County and Lessee.

              28. MORTGAGE OF LESSEE'S LEASEHOLD INTEREST.

                  A. Notice of Default under Mortgage or Lease. Lessee shall
have the right at any time and from time to time to mortgage this Lease and/or
assign or hypothecate Lessee's interest in this Lease and/or in the Improvements
as security for a loan, provided that this Lease is not subordinated to the
terms of any assignment or Mortgage. Any subtenant or sub-subtenant (but no
tenant of any sub-subtenant) of Lessee shall have the right at any time and from
time to


                                       36
<PAGE>   43
time to mortgage its sublease and/or assign or hypothecate its interest in such
sublease and/or in the Improvements as security for a loan, and Lessee may
subordinate its interest in such sublease to the terms of any such assignment or
mortgage, provided that this Lease is not subordinated to the terms of any
assignment or Mortgage.

                  B. Leasehold Mortgagee Right to Notice and Cure. Any Leasehold
Mortgagee with respect to which County has received a written notice specifying
the name and address of such Leasehold Mortgagee, shall be given (by personal
delivery or by certified mail, return receipt requested) by County a copy of
each notice of default by Lessee or other notice or demand to or upon Lessee, at
the same time as and whenever such notice of default or other notice or demand
shall thereafter be given by County to Lessee, addressed to such Leasehold
Mortgagee at the address last furnished to County. No notice of a default by
Lessee or demand upon Lessee shall be deemed to have been given by County to
Lessee unless and until a copy thereof shall have been given to each Leasehold
Mortgagee with respect to which County has been notified. County will accept
performance by any such Leasehold Mortgagee of any covenant, condition or
agreement on Lessee's part to be performed hereunder with the same force and
effect as though performed by Lessee, and any Leasehold Mortgagee which performs
any covenant, condition or agreement shall be subrogated to any and all rights
of Lessee with respect thereto. Nothing contained in this Lease shall obligate
any Leasehold Mortgagee to cure any default of Lessee under this Lease or
constitute an assumption by any Leasehold Mortgagee of the obligations of Lessee
under this Lease.

                  C. Leasehold Mortgagee as Holder of Lessee's Interest. A
Leasehold Mortgagee may become the legal owner and holder of Lessee's interest
under this Lease by


                                       37
<PAGE>   44
foreclosure of its Mortgage, or as a result of the assignment of this Lease in
lieu of foreclosure, whereupon (but in no event before becoming such legal owner
or holder) such Leasehold Mortgagee shall immediately become and remain liable
under this Lease, so long as (but no longer than) such Leasehold Mortgagee is
entitled to possession of the Premises.

                  D. Certain Restrictions During Leasehold Mortgage. So long as
any Mortgage is in existence, and no default exists hereunder which has not been
cured (by Lessee, any Leasehold Mortgagee or any Subtenant, as defined herein)
within the period of time provided herein, County shall not accept a surrender
of the Premises or a termination or modification of this Lease, prior to the
expiration of this Lease, without the prior written consent of all Leasehold
Mortgagees (of whom County has received prior written notice). Any right or
remedy which permits Lessee to terminate this Lease shall be conditioned on the
written consent to such termination by all Leasehold Mortgagees.

                  E. New Financing. In the event any Leasehold Mortgagee
requires, as a condition of providing financing, that modifications to this
Lease be obtained, and provided that such modifications do not, in County's
reasonable judgment, unreasonably increase County's obligations or reduce
County's rights under this Lease, then Lessee shall submit to County a written
amendment to this Lease incorporating such required modifications, and County
shall execute such amendment and deliver the same to Lessee within thirty (30)
days after receipt of such amendment.

                  F. Assignment by Leasehold Mortgagee. Any party, including a
Leasehold Mortgagee or the assignee of such Leasehold Mortgagee, that becomes
the owner of or acquires any interest in this Lease pursuant to foreclosure and
sale or by assignment in lieu of foreclosure,


                                       38
<PAGE>   45
may sell, assign, transfer or otherwise dispose of this Lease or its interest in
this Lease without the consent of County. All rights and references herein to a
Leasehold Mortgagee, shall be read to include the assignee of such Leasehold
Mortgagee. Notice of any such assignment shall be given to County.

                  G. Notice of Mortgages. Lessee shall give County notice of any
recorded mortgages or liens upon Lessee's leasehold interest in the Premises in
connection with the financing of the Premises.

              29. SUCCESSORS AND ASSIGNS; SUBLEASING.

                  County acknowledges that Lessee intends to enter into a
sublease with BPG Industrial Partners II, LLC, for a portion of the Premises,
and that BPG Industrial Partners II, LLC intends to sub-sublease such portion of
the Premises to Lessee's wholly-owned subsidiary, MAGENTA Corporation. County
hereby consents to such sublease and such sub-sublease. Lessee shall have the
right, without the consent of the County, to assign this Lease to, or enter into
a sublease with, or permit BPG Industrial Partners II, LLC or any other
subtenant of Lessee to assign its sublease to, or enter into a sub-sublease with
(i) any entity which controls, is controlled by or is under common control with,
Lessee for any use allowed by the Covenants, or (ii) any other party for any
manufacturing and industrial use allowed by the Covenants. Lessee shall not
assign this Lease to, or enter into a sublease with, or permit BPG Industrial
Partners II, LLC or any other subtenant of Lessee to assign its sublease to, or
enter into a sub-sublease with any party other than an entity which controls, is
controlled by or is under common control with, Lessee for any use other than a
manufacturing and industrial use allowed by the Covenants, without the consent
of County, which shall not be unreasonably withheld, conditioned or



                                       39
<PAGE>   46
delayed. Any sub-subtenant shall have the right to sublease all or any portion
of its subleased premises without the necessity of obtaining the County's
consent, provided that such sub-sub-sublease is subject to the use restrictions
set forth in this paragraph. No assignment or subletting shall be deemed to
release Lessee from its obligations under this Lease.

                  Any subtenant or sub-subtenant (each a "Subtenant", which term
does not include any tenant of a sub-subtenant) of Lessee, with respect to which
County has received a written notice specifying the name and address of such
Subtenant, shall be given by County a copy of each notice of default by Lessee
or other notice or demand to or upon Lessee, at the same time and in the same
manner as and whenever such notice of default or other notice or demand shall
thereafter be given by County to Lessee, addressed to such Subtenant at the
address last furnished to County. No notice of a default by Lessee shall be
deemed to have been given by County to Lessee unless and until a copy thereof
shall have been given to each Subtenant with respect to which County has been
notified. In the event that Lessee receives notice from the County of a default
by Lessee and such default is not cured by Lessee pursuant to the provisions of
this Lease, County shall, prior to commencing any judicial proceedings or taking
any other action, including ejectment or dispossession proceedings, to obtain
possession of the Premises, in addition to giving the notice to each Subtenant,
give a second notice of the failure of Lessee to cure such default to each
Subtenant at the expiration of the period within which Lessee may cure as set
forth in this Lease, and the Subtenant may proceed to cure any such failure.
County will accept performance by any such Subtenant of any covenant, condition
or agreement on Lessee's part to be performed hereunder with the same force and
effect as though performed by Lessee, whether or not Lessee is in default under
this Lease at the time of such performance. Any


                                       40
<PAGE>   47
Subtenant which performs any covenant, condition or agreement shall be
subrogated to any and all rights of Lessee with respect thereto. Nothing
contained in this Lease shall obligate any Subtenant to cure any default of
Lessee under this Lease or constitute an assumption by any Subtenant of the
obligations of Lessee under this Lease.

                  County and Lessee agree that all of the terms, covenants and
conditions, agreements, rights, privileges, obligations and duties contained in
this Lease shall be construed to be covenants running with the land, and all
rights and liabilities herein given to, or imposed upon, the respective parties
hereto shall extend to and bind the respective successors and assigns of said
parties; and if Lessee shall be comprised of more than one individual or entity,
they shall all be bound jointly and severally by the terms, covenants and
agreements herein.

                  So long as any sublease or sub-sublease is in effect, and no
default exists hereunder which has not been cured (by Lessee, any Subtenant or
any Leasehold Mortgagee) within the period of time provided herein, County shall
not accept a surrender of the Premises or a termination or modification of this
Lease, prior to the expiration of this Lease, without the prior written consent
of all Subtenants (of whom County has received prior written notice). Any right
or remedy which is expressly granted in this Lease allowing Lessee to terminate
this Lease shall be conditioned on the written consent to such termination by
all Subtenants.

                  County agrees that in the event this Lease is terminated,
County will not disturb the rights of any Subtenant, so long as (i) such
Subtenant complies with all of the material terms of its sublease or
sub-sublease, as applicable, and (ii) such sublease or sub-sublease, as
applicable, is expressly subject to this Lease; and County in the exercise of
its rights and remedies under this Lease shall not deprive any such Subtenant of
possession or occupancy of



                                       41
<PAGE>   48
the area of the Premises, or portion thereof, covered by its sublease or
sub-sublease, as applicable, during the term thereof or join any such Subtenant
as a party in any action or proceeding to enforce or terminate this Lease or
obtain possession of said area for any reason. The provisions of this paragraph
shall be self-executing but County, upon request by Lessee or any Subtenant,
agrees to execute additional documentation to effectuate the provisions of this
paragraph.

              30. QUIET ENJOYMENT, TITLE TO LAND AND IMPROVEMENTS.

                  A. Quiet Enjoyment. Upon payment by Lessee of the rents herein
provided and upon the observance and performance of all covenants, terms and
conditions on Lessee's part to be observed and performed, Lessee shall peaceably
and quietly hold and enjoy the Premises for the term hereby demised without
hindrance or interruption by County or any other person or persons lawfully or
equitably claiming by, through or under County, subject to the terms and
conditions of this Lease.

                  B. Title. County represents that it owns the Premises in fee
simple, and that, except for the Covenants and the Development Plan, there is no
encumbrance upon the Premises that is superior to this Lease or that would
adversely affect the use or value of the Premises. County covenants that it
shall not at any time hereafter (except for a sale of the fee simple interest to
Lessee as referred to herein) convey or sell any interest of County in the
Premises unless such conveyance or sale is made subject to this Lease and any
Leasehold Mortgage. County further represents that it has the right to make this
Lease and covenants that it will execute or procure any further necessary
assurances of title that may be reasonably required for the protection of
Lessee. County and Lessee each represent to the other that it has the full
right,


                                       42
<PAGE>   49
power, and authority to enter into this Lease for the Term and that the Premises
may be used by Lessee during the Term for the purposes herein set forth provided
Lessee conforms to the provisions of this Lease and all applicable laws and
regulations. Without limiting the generality of the foregoing, County shall
execute and deliver to Lessee (or to any Leasehold Mortgage), within forty-five
(45) days after request therefor, an Estoppel Certificate and Consent in
substantially the form of Exhibit F attached hereto and made a part hereof. As
consideration for the execution of this Lease, County acknowledges that Lessee,
or any subtenant or sub-subtenant of the Lessee, shall hold title to all of the
Improvements as long as this Lease is in effect.

              31. SURRENDER - WAIVER AND AMENDMENT.

                  No agreement to amend or to accept a surrender of this Lease
or a waiver of either party's obligations hereunder shall be valid unless in
writing signed by County and Lessee. No employee of County or its agent shall
have any power to accept the keys of the Premises prior to the termination of
this Lease. The delivery of keys to any employee of County or its agent shall
not operate as a termination of this Lease or a surrender of the Premises. The
failure of any party to seek redress for violation of, or to insist upon the
strict performance of any covenant or condition of this Lease, shall not prevent
a subsequent act, which would have originally constituted a violation of this
Lease from having all the force and effect of an original violation of this
Lease. The receipt and acceptance by County of rent with knowledge of the breach
of any condition or covenant of this Lease shall not be deemed a waiver of such
breach. The right to enforce any such condition or covenant is in the sole
jurisdiction of County. The failure by either party to enforce any of the
conditions or covenants set forth herein or hereinafter



                                       43
<PAGE>   50
adopted, against the other or against any other lessee in the Life Sciences
Center, shall not be deemed a waiver of any such conditions or covenants.

              32. NON-DISCRIMINATION IN EMPLOYMENT AND SERVICES.

                  Lessee agrees to comply with the non-discrimination in
employment policies in County contracts as required by Section 11B-33 and
Section 27-19 of the Montgomery County Code 1994, as amended, as well as all
other applicable state and federal laws regarding employment discrimination.

              33. DISPUTES.

                  A. Mediation of Disputes. Except as otherwise set forth in
subparagraph B of this Paragraph 33, any claim or controversy arising out of or
relating to this Lease, or the breach thereof, may, at the option of either
party hereto, be submitted to mediation under mediation rules to be mutually
agreed upon. The party electing mediation shall initiate the mediation by filing
a request for mediation with the other party. The parties agree as follows with
respect to such mediation:

                     (i) The cost of the mediation, including the cost of the
mediator, shall be borne equally by the parties;

                     (ii) Mediation shall occur in Montgomery County, Maryland,
at a time and location to be designated by the mediator;

                     (iii) In the mediation sessions, the parties shall endeavor
in good faith to resolve the claim or controversy at issue;

                     (iv) Any party or the mediator shall have the right to
terminate the mediation at any time after the first mediation session; and

                                       44
<PAGE>   51
                     (v) Neither party may make any disclosure of the existence
or results of the mediation without the prior written consent of the other
party. The mediator may not make any disclosure of the existence or results of
the mediation without the prior written consent of both parties. No discussions
in the mediation shall be admissible in any litigation between the parties, and
the mediator shall not be subject to subpoena to testify to any communication
between the mediator and either party.

                  B. Exceptions. County shall not be required to mediate any
default or breach of this Lease which entitles County, under this Lease, to
terminate this Lease. If Lessee desires to mediate the issue of whether it is
responsible for the payment of any rental or other amount or the performance of
any material obligation claimed by County to be then due or overdue under this
Lease, County may require, as a condition of agreeing to mediate such issue,
that Lessee pay such disputed rental or other amount or perform such disputed
obligation prior to the commencement of the mediation. Either party may seek
injunctive relief from a court pending the outcome of any mediation.

              34. CONTRACT SOLICITATION.

                  Lessee represents that Lessee has not retained anyone to
solicit or secure this Lease from Montgomery County, Maryland, upon an agreement
or understanding for a commission, percentage, brokerage or contingent fee,
excepting for bona fide employees or bona fide established commercial, selling
or leasing agencies retained by Lessee for the purpose of securing business or
an attorney rendering professional legal services consistent with applicable
canons of ethics.

              35. PUBLIC EMPLOYMENT.

                  Lessee understands that unless authorized under Section 1lB-52
and Chapter 19A of the Montgomery County Code 1994, as amended, it is unlawful
for any person transacting



                                       45
<PAGE>   52
business with County to employ a public employee for employment contemporaneous
with his or her public employment.

              36. GOVERNING LAW, SEVERABILITY, CASUALTY, CONDEMNATION AND
                  COMPLIANCE.

                  A. Governing Law. This Lease shall be construed and governed
by the laws of the State of Maryland wherein the Premises and the Shady Grove
Life Sciences Center are located. Should any provisions of this Lease and/or of
its conditions be deemed illegal or not enforceable under the laws of the said
jurisdiction, it or they shall be considered severable, and the balance of this
Lease and its conditions shall remain in force and be binding upon the parties
as though such provisions had never been included.

                  B. Lease not Redeemable. The purpose of this Lease is not
primarily residential and shall not be redeemable as provided in Section 8-110 
of the Real Property Article, Annotated Code of Maryland.

                  C. Casualty Damage. In the event the Facility or other
Improvements shall be damaged or destroyed by fire or other casualty, Lessee, at
its option and at its sole cost and expense, shall either repair, reconstruct or
replace the Improvements or portion thereof so damaged or destroyed (whichever
is reasonably required), or demolish the Facility and other Improvements and
restore the Premises to a safe and orderly condition in compliance with all
laws. This Lease shall remain in full force and effect and there shall be no
abatement of annual base rent or any other amount payable under this Lease.

                  D. Condemnation. If the entire Premises are condemned for any
public use or purpose by a public authority, unless Lessee exercises the
Purchase Option prior to the date of


                                       46
<PAGE>   53
surrender of possession, this Lease shall cease and rent be accounted for as of
the date of surrender of possession. In the event of a partial taking, unless
Lessee exercises the Purchase Option prior to the date of surrender of
possession, a pro rata reduction in the rent and the purchase price under the
Purchase Option shall be provided in the proportion which the property so taken
or condemned bears to the entire Property originally devised. Further, in the
event of any taking or condemnation, unless Lessee exercises the Purchase Option
prior to the date of surrender of possession, Lessee shall not be entitled to
claim any value for the underlying fee interest or the Purchase Option, but may
claim the value of the leasehold interest and Improvements from the condemning
authority, and both County and Lessee shall be entitled to claim, prove and
receive in the condemnation proceeding such awards as may be allowed for their
respective interests in fixtures, equipment and other property. If the entire
Premises are condemned for any public use or purpose by a public authority, and
Lessee exercises the Purchase Option prior to the date of surrender of
possession, then the purchase price payable by Lessee for the Property shall be
the entire price set forth on the Rent/Purchase Price Schedule for the date of
closing on such purchase, and Lessee shall be entitled to claim, prove and
receive in the condemnation proceeding such awards as may be allowed for the fee
interest in the Property and for the Improvements and all fixtures, equipment
and other property therein or thereon. County shall give Lessee prompt written
notice of any condemnation or threatened condemnation of the Premises.

                  E. Compliance with Law. It is understood, agreed and
covenanted by Lessee that it shall promptly comply with, observe and perform all
of the requirements of all the statutes, ordinances, rules, orders and
regulations now in effect or hereinafter promulgated whether


                                       47
<PAGE>   54
required by the Federal Government, the State of Maryland, County, in its
governmental capacity or the Montgomery County Fire Marshal.

                  F. No Waiver of Governmental Immunity. The responsibilities
and obligations of County as set forth in this Lease shall not constitute a
waiver by County of any provision of the Local Government Tort Claims Act,
Section 5-401, et seq., of the Courts and Judicial Proceedings Article,
Annotated Code of Maryland.

                  G. Limitation of Liability. County's liability to Lessee, its
employees, agents, visitors, tenants, licensees or concessionaires for recovery
of any loss, expense or judgment under this Lease shall be limited as set forth
herein and as set forth in the Local Government Tort Claims Act, Section 5-401,
et seq., of the Courts and Judicial Proceedings Article, Annotated Code of
Maryland.

                  H. Limitation of Lessee's Liability. Notwithstanding any
contrary provision contained in this Lease, County agrees that the obligations
of Lessee hereunder shall not constitute personal obligations of the officers,
directors, shareholders, partners or members of Lessee.

              37. RECORDING.

                  Lessee and County shall have the right to record this entire
Lease or to execute a Memorandum of Lease and have it properly acknowledged for
the purpose of recording. Such Memorandum of Lease shall have included therein
such of the provisions hereof as may be requested by either of the parties. The
cost of recording this entire Lease or such Memorandum


                                       48
<PAGE>   55
of Lease (including all stamps, conveyance, recordation and other taxes incident
thereto) shall be borne solely by Lessee.

              38. ENTIRE AGREEMENT.

                  This Lease, Exhibits, and Addenda, if any, attached hereto and
forming a part hereof, sets forth all the covenants, promises, agreements,
conditions and understandings between County and Lessee concerning the Premises
and there are no covenants, promises, agreements, conditions or understandings,
either oral or written, between them other than as herein set forth. Except as
herein otherwise provided, no subsequent alteration, amendment, change or
addition to this Lease shall be binding upon County or Lessee unless reduced to
writing and signed by them.

              39. NOTICE. All notices required or permitted hereunder shall be
deemed to have been given if delivered by a reputable messenger, overnight
delivery service, facsimile or mailed in any United States Post Office by
certified mail, return receipt requested, postage prepaid, addressed to County
or Lessee, respectively, at the following addresses or to such other addresses
as the parties may designate in writing from time to time. All notices shall be
deemed to be received on the date of delivery by messenger or overnight delivery
service, the date indicated by a facsimile confirmation receipt signed by the
recipient, or three (3) business days after depositing them with the United
States Post Office.

            Notice of the identity and address of any Leasehold Mortgagee and
any Subtenant shall be in the form of a written notice sent to County in
accordance with this Section.

COUNTY:                               LESSEE:

Montgomery County, Maryland           BioReliance Corporation


                                       49
<PAGE>   56
Department of Public Works and         9900 Blackwell Road
         Transportation                Rockville, Maryland 20850
Division of Facilities and Services    Attention: Capers W. McDonald, President
Office of Real Estate Management       Facsimile: (301) 738-1033
110 North Washington Street
Rockville, Maryland 20850
Facsimile: (301) 217-6080

With a copy to:                         With a copy to:

County Attorney                         The Buccini/Pollin Group, Inc.
101 Monroe Street, Third Floor          250 Park Avenue, 17th Floor
Rockville, Maryland 20850               New York, New York 10177
Facsimile: (301) 217-2662               Facsimile: (212) 949-5995

                                        And a copy to:

                                        Shulman,Rogers,Gandal,Pordy & Ecker,P.A.
                                        11921 Rockville Pike, Suite 300
                                        Rockville, Maryland 20852
                                        Attention:  Lawrence A. Shulman, Esquire
                                        Facsimile:  (301) 230-2891

                                        And a copy to:

                                        Arent Fox
                                        1050 Connecticut Avenue, N.W.
                                        Washington, D.C. 20036
                                        Attention: Richard L. Brand, Esquire
                                        Facsimile: (202) 857-6395


              40. NON-MERGER.

                  The fee title of County and the leasehold estate of Lessee
shall, at all times during the period of this Lease, be separate and apart and
shall in no event be merged, notwithstanding the fact that this Lease or the
leasehold estate created hereby, or any interest in either thereof, may be held
directly or indirectly by or for the account of any person who shall own the fee



                                       50
<PAGE>   57
estate in the Premises or any portion thereof; and no provisions contained in
this Lease shall survive the execution of any deed conveying the fee simple
title to any entity owning the leasehold estate but shall be merged by operation
of law upon the execution of such deed.

            41. SUBORDINATION OF LEASE. County will not subordinate this Lease
to any deed of trust or similar security interest which may hereafter be
placed on Lessee's leasehold interest in the Premises.

            42. CAPTIONS. PRONOUNS. The captions and paragraph numbers appearing
in this Lease are inserted only as a matter of convenience and in no way
define, limit, construe, or describe the scope or intent of this Lease,
nor in any way affect this Lease.

            The use of the neuter singular pronoun to refer to County or Lessee
shall be deemed a proper reference even though County or Lessee may be an
individual, a partnership, a joint venture, a corporation, or a group of two or
more individuals, partnerships, joint ventures or corporations. The necessary
grammatical changes required to make the provisions of this Lease apply in the
plural sense shall in all instances be assumed as though in each case fully
expressed.

            43. SURVIVAL. The following obligations shall survive the expiration
or termination of this Lease: (a) any obligation herein permitted to be
performed after the expiration or termination of this Lease; (b) any obligation
not reasonably susceptible to performance prior to the expiration or termination
of this Lease; and (c) any obligation, required hereunder to be performed at or
before the expiration or termination of this Lease, not so performed.

            44. MISCELLANEOUS PROVISIONS.

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<PAGE>   58
                  A. Days. If the date on which either County or Lessee is
required to take or complete an action hereunder is not a business day (as
defined below), the action shall be taken or completed on the next succeeding
business day. For purposes hereof, "business day" means any day other than a
Saturday, Sunday or federal holiday.

                  B. Certain Terms. For purposes of this Lease, there shall be
no distinction between the terms "breach" and "default."

                  C. Authority. County and Lessee hereby covenant each for
itself, that each has full right, power and authority to enter into this Lease
upon the terms and conditions herein set forth.

                  D. No Partnership. Nothing contained in this Lease shall be
deemed or construed to create a partnership or joint venture of or between
County and Lessee, or to create any other relationship between the parties other
than that of lessor and lessee.

                  E. Consequential Damages. Notwithstanding anything to the
contrary in this Lease, in no event shall either County or Lessee be liable to
the other for consequential damages, except as set forth in Section 13.C.

         IN WITNESS WHEREOF, the parties hereto do hereby execute this Lease as
of the day and year first above written.

WITNESS OR ATTEST:                MONTGOMERY COUNTY, MARYLAND


                                  By:
----------------------------         -----------------------------------------
                                     Douglas M. Duncan


                                       52
<PAGE>   59
                                     County Executive


WITNESS OR ATTEST:                BIORELIANCE CORPORATION


                                  By:
----------------------------         -----------------------------------------
                                     Capers W. McDonald
                                     President


APPROVED AS TO FORM AND LEGALITY
OFFICE OF THE COUNTY ATTORNEY


By:
   ---------------------------

Dated:
      ------------------------


STATE OF MARYLAND,                           , to wit:
                  --------------------------
         ON THIS     day of                     , 1998, before me, the
                ---         -------------------
undersigned officer, personally appeared Douglas M. Duncan, County Executive for
Montgomery County Maryland, known to me to be the person whose name is
subscribed to the foregoing, who did fully acknowledge that he executed the same
as his voluntary act and deed for the purposes therein contained.

         WITNESS my hand and official seal the same day and year first above
written.


                                         -----------------------------------


                                       53
<PAGE>   60
                                                         Notary Public
My Commission Expires:
                      -------------------------

STATE OF MARYLAND,                       , to wit:
                    --------------------
         ON THIS     day of                 , 1998, before me, the undersigned
                ----       -----------------
officer, personally appeared Capers W. McDonald, President of BioReliance
Corporation, known to me to be the person whose name is subscribed to the
foregoing, who did fully acknowledge that he executed the same as his voluntary
act and deed for the purposes therein contained.

         WITNESS my hand and official seal the same day and year first above
written.


                                            -----------------------------------
                                            Notary Public
My Commission Expires
                     ------------------


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