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                                                                Exhibit 10.4

                           COMMERCIAL LEASE COMMITMENT

                                   BUILDING C5

                             CONSTRUCTION COMMITMENT


Signed December 24, 1998 by:

PASTEUR MERIEUX Serums et Vaccins,

A French SOCIETE ANONYME of the PASTEUR MERIEUX CONNAUGHT group, capitalized at
FRF 1,698,859,000, registered in the Lyons Trade Register under Number B 349 505
370, with corporate offices at 58 avenue Leclerc, 69007 Lyons,

Represented by  Herve Tainturier, duly authorized for this purpose,

Referred to hereinafter as "PMC" or the "Lessor,"

Party of the first part;

AND:

IMTIX-SANGSTAT,

A French SOCIETE PAR ACTIONS SIMPLIFIEE, capitalized at FRF 77,436,400,
registered in the Lyons Trade Register under Number B 418 661 039, with
corporate offices at 58 avenue Debourg, 69007 Lyons,

Represented by Gilles Alcerici, President,

Referred to hereinafter as "IMTIX-SANGSTAT" or the "Lessee,"

PARTY OF THE SECOND PART;

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                                    WHEREAS:

PASTEUR MERIEUX Serums et Vaccins is a pharmaceutical company that develops,
manufacturers and sells serums and vaccines for therapeutic use for humans.
These products are manufactured and inspected in several industrial sites,
including the site of Marcy l'Etoile.

On September 30, 1998, PMC transferred to IMTIX-SANGSTAT, as part of a spin-off,
the business branch related to transplant products.

IMTIX-SANGSTAT wishes to continue the manufacture of the products Thymoglobulin
and Lymphoglobulin in buildings C4 (for the Thymoglobulin) and V3a (for the
Lymphoglobulin) on the PMC site in March L'Etoile and, for this purpose, the
parties signed two commercial leases on September 30, 1998.

The building V3a, in which the product Lymphoglobulin is manufactured on the
date of signature of this lease, was supposed to have been modified and repaired
to comply with regulatory requirements. However, during the negotiations between
PMC and the parent company of IMTIX SANGSTAT (SangStat Medical Corp (SMC)), SMC
expressed a wish to obtain premises for its subsidiary IMTIX SANGSTAT for use as
offices and two laboratories--one for controls and the other for development.

To meet SMC's request, PMC proposed the construction of a building C5, adjacent
to C4, containing two laboratories, offices and a section for the manufacture of
the Lymphoglobulin intended to replace Building V3a.

Until PMC takes possession of Building C5, IMTIX-SANGSTAT shall continue to
produce Lymphoglobulin in building V3a, the subject of a commercial lease.

NOW, THEREFORE, IT HAS BEEN AGREED AS FOLLOWS:

ARTICLE 1 - CONSTRUCTION PROJECT

1.     FILING THE CONSTRUCTION PERMIT

PMC filed construction permit No. 69 127 98 Y 002 on December 16, 1998, which
will be revised in order to comply with the plans attached to this lease
commitment (Schedule 1).

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2.     CONSTRUCTION COMMITMENT

PMC agrees to build a building C5 as shown in Schedule 1. For this purpose, PMC
will sign, within a reasonable period after the signature of this lease
commitment, a real estate promotion agreement or any other document with
equivalent effect for the construction of Building C5 with the engineering
company that was responsible for the construction of Building C4 or, if not with
this company, with a legally solvent engineering company.

3.     DESCRIPTION OF THE PROJECT

In accordance with the plans attached to this lease commitment, Building C5
shall be built on three levels:

-      a first level for storage, technical space and the development
       laboratory;
-      a second level devoted to the section for the production of
       Lymphoglobulin
-      a third level for offices and the control laboratory.

This represents useable surface area of approximately 2,000 m (TO THE POWER OF
2), with a ground area of about 820 m (TO THE POWER OF 2). Building C5 will be
a quality equivalent to Building C4.

The completion of Building C5 is scheduled no later than June 24, 2000.

It is specified that all the minor differences between the design calculates and
the areas resulting from the plans attached hereto and the actual dimensions of
said premises shall not justify any increase or reduction in the rent; the
parties refer to the contents of the premises as they exist or shall exist.

Given the non-completion of Building C5 on the date of signature of this
Agreement, the Lessor reserves the right to make certain modifications or
improvements in the services set forth, the extent of which shall first be
communicated to the Lessee.

The Lessee declares that it agrees to lease building C5 as described and as it
shall exist, without the need to provide a more detailed description, subject to
the terms set forth below and the ordinary legal conditions that may be applied.

ARTICLE 2 - POSSESSION - AVAILABILITY OF BUILDING C5

2.1    DEFINITION AND COMPLETION DEADLINE

Because this lease commitment is granted for a future state of completion, it is
agreed as follows:

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The completion date for Building C5 is scheduled no later than June 24, 2000,
and the Lessor will make Building C5 available to the Lessee before that date
pursuant to the provisions of the Building and Housing Code, and after
validation by the Lessor of the water loop and the classification of Building C5
as "Operational Facilities" pursuant to the provisions of Article 2.2 below; it
is understood that the Lessor agrees to perform all formalities with regard to
said validations as soon as possible.

The completion date may be extended by relays resulting from events of force
majeure as defined by law or, more generally, by a legitimate cause for the
suspension of the delivery deadline.

For the application of this articles, the following will be considered
legitimate causes for suspension of the delivery deadline:

-    bad weather days as defined by the labor regulations;
-    strikes, whether general, specific to the building industry or specific to
     the companies working on the construction site;
-    administrative or court orders to suspend or stop the work;
-    disturbances resulting from hostilities, revolutions, construction
     disasters or accidents.

If an event of force majeure or a legitimate cause for the suspension of the
delivery deadline occurs, the date scheduled for the completion of the work will
be postponed for a period equal to the period during which the event in question
has prevented continuation of the work. PMC must inform IMTIX-SangStat as soon
as possible of the event of force majeure or the legitimate cause for suspension
and of the delays projected for the availability of Building C5. The Lessor
shall make Building C5 available to the Lessee at this period pursuant to the
provisions of the Building and Housing Code.

2.2    DATE OF AVAILABILITY OF BUILDING C5

The date on which the Lessor will make Building C5 available to the Lessee will
be the latest of the following dates:

-      completion of Building C5; the notion of completion is the definition
       given by Article R. 261-1 of the Building and Housing Code;
-      date of removal of the major legitimate reservations, if any, expressed
       by the Lessee during the first availability meeting, pursuant to the
       provisions of Article 2.3 hereinabove [sic];
-      after the Lessor validated the water loop and Building C5 is classsified
       as "Operational Facilities."

It is specified, as needed, that the validation of the process equipment and the
production of Lymphoglobulin in Building C5 is the responsibility of
IMTIX-SangStat, and may not in any event delay the turnover of Building C5 and
the possession by IMTIX-SangStat pursuant to the provisions of this lease
commitment.

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2.3    VERIFICATION OF COMPLETION - REPORT

Upon completion of the work as defined in Article R. 261-1 of the Building and
Housing Code, the Lessor shall notify the Lessee by registered letter with
return receipt, along with a certificate verifying the completion of Building
C5, in order to set a meeting to establish the joint report verifying the
completion of Building C5, its condition and availability.

If there are major legitimate reservations expressed in the Report, taking
possession of Building C5 shall be delayed until the withdrawal of said
reservations, which must be performed within six months from the date of the
Report. It is specified that a major reservation is one that prevents normal
operation of the leased premises. Upon completion of the work resulting from the
major reservations expressed, the Lessor shall notify the Lessee by registered
letter with return receipt, along with a certificate verifying the completion of
Building C5, in order to set a meeting to establish the second joint report
verifying the completion of Building C5, its condition and availability for the
Lessee.

If the Lessee is absent from the first meeting or is not represented, the Lessor
shall notify the Lessee a second time, in the same forms as stipulated for the
first notification, within fifteen days from the first meeting.

If the Lessee is absent for the second Report, or is not represented, the Lessor
shall notify the Lessee a second time, in the same forms as stipulated for the
first notification, within fifteen days after the first meeting [SIC].

If the Lessee is absent or not represented at the second meeting and without an
amicable agreement to the contrary, the Lessee shall be deemed to have taken
possession of Building C5, which shall be deemed in conformity, and the Lessee
shall, as a result, be liable for the rent as of that date. The Lessee shall be
required to take Building C5 under the provisions of this lease, effective on
that date.

If the Lessee believes that it has not accepted the turnover of Building C5, and
if there is no agreement between the parties on the legitimate nature of the
dispute, they shall refer the matter to an expert named by mutual agreement, or
an expert named, at the request of the first party to act, by the Chief Judge of
the Lyons Regional Court (TRIBUNAL DE GRANDE INSTANCE), within ten days after
noting the Lessee's refusal.

The expert must make a decision within one month from the date of his nomination
and shall inform the parties of his ruling by registered letter with return
receipt.

If the designated expert believes that the building shall be considered
available, the Lessee shall be deemed to have taken Building C5 with all
consequences attached to this event pursuant to this lease. The expert's fees
and expenses shall be paid by the Lessee or the Lessor depending on whether or
not the expert has ruled that the building is complete and the Lessee is able to
take possession of Building C5.

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The Lessor and the Lessee expressly waive any action to appeal the expert's
rulings.

2.4    TERMINATION OF THE COMMERCIAL LEASE FOR BUILDING V3a

The Parties undertake to terminate the commercial lease for V3a within a maximum
period of 6 months from the date on which Building C5 successfully allows
industrial and commercial production for Lymphoglobulin, and no later than 1
month after the effective date of the commercial lease for Building C5. It is
specified that successful production means continuous production of
lymphoglobulin for at least three months without significant problems. In
addition, the parties acknowledge that the Lessee may not, under any
circumstances, occupy Building V3 as of the effective date of the commercial
lease for C5 without a legitimate reason.

2.5    RENT ALLOWANCE

The Lessor, under commercial lease V3a, shall grant a total rent allowance (all
charges included) to the Lessee for said lease as of the effective date of
commercial lease C5, for a maximum period of 12 months.

ARTICLE 3 - INTENDED USE

The Lessee may use Building C5 for industrial use to carry out the activity of a
pharmaceutical company for the manufacture of all or part of the pharmaceutical
product LYMPHOGLOBULIN, as a quality control laboratory for the products
Thymoglobulin, Lymphoglobulin, Celsior, Antilfa, and as a development laboratory
for the aforementioned products.

The Lessee may also use Building C5 for the manufacture of the monoclonal
antibody Anti-LFA1, known under the name of ANTILFA.

Any other use is excluded, and no activity other than the activity cited above
may be performed that could call into question the use or the nature of Building
C5.

Moreover, the Lessee must maintain the leased premises in permanent operating
condition.

The Lessee also undertakes to inform the Lessor of any significant change, which
has consequences for the environment, in the activity to manufacture the
pharmaceutical products referenced above, both in terms of composition and the
quality produced, pursuant to the provisions of Article 11 below.

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As Building C5 has special status with regard to the regulations governing the
environment and the pharmaceutical industry, the Lessee is prohibited from any
new act or activity that could change its status.

ARTICLE 5 - TERM OF THE LEASE

The effective date of the lease will be the date of availability of Building C5
as defined in Article 2.2 of this Agreement.

The lease is granted for a term of 15 years from the effective date, from which
is subtracted the period between (a) the effective date of the V3a lease, in
this instance September 30, 1998, and (b) the effective date of the commercial
lease for Building C5.

The Lessee shall have the option to terminate this lease, at any time, by
notifying the Lessor twelve months before the expiration date, in the forms set
forth in the Decree of September 30, 1953.

At the same time, the Lessor shall have the option to refuse renewal of this
lease at expiration in accordance with the forms and conditions stipulated by
the Decree of September 30, 1953 and all subsequent texts amending or completing
said decree.

This lease may also be terminated at the Lessor's initiative if the Lessee fails
to meet its substantive obligations under the conditions defined in Article 14
below.

ARTICLE 5 - RENT

This lease is granted and accepted in consideration for an annual rent
(including charges) excluding tax, which shall be calculated at the time
Building C5 is made available as follows:

Annual rent (excluding tax and including charges) = [Total amount of the Direct
Investment - FRF Eight Million (8,000,000) (excluding tax and including
charges)] / 12.

However, the parties have decided by mutual agreement to set a ceiling and a
floor to the amount of the annual rent that may result from the calculation
specified above. Therefore, the annual rent may not be greater than FRF Two
Million One Hundred Thousand (2,100,000) (excluding tax and including charges),
and may not be less than FRF One Million Six Hundred Thousand (1,600,000)
(excluding tax and including charges).

All reasonable and direct expenses incurred by PMC for the construction of
Building C5 shall be integrated in the calculation of the total amount of the
Direct Investment. The amount of the Direct Investment shall be calculated using
a calculation method similar to the one normally used by PMC in the construction
of its

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industrial buildings and, in particular, the one that was used for Building C4.
The Lessee shall be given the possibility, when Building C5 is made available,
of conducting an audit of the Direct Investment within three months after
Building C5 is made available. This audit option for IMTIX-SangStat may be
exercised, however, only after IMTIX-SangStat has notified PMC of the visit by
its employees with advance notice of 15 days.

This visit may be postponed at the request of PMC to limit the inconveniences,
but this postponement may not exceed 15 days.

In the event the Lessee challenges the amount of the Direct Investment, the
matter shall be referred to an expert named by mutual agreement or, to an expert
named at the request of one party by the Chief Judge of the Lyons Regional
Court, within ten days of the challenge made by the Lessee by registered mail
with return receipt.

The expert must rule within one month from the date of his appointment and shall
inform the parties of his ruling by registered letter with return receipt.

The fees and expenses of the expert shall be paid by the Lessee or the Lessor
based on whether or not the Lessee's challenge is upheld by the expert.

The Lessor and the Lessee expressly waive any appeal of the expert's ruling.

The applicable VAT at the rate in effect, or any other tax substituted for the
VAT, shall be added to the rent, as determined by the calculation above, and
paid by the Lessee.

ARTICLE 6 - PAYMENT OF THE RENT

The rent, plus the VAT as defined in Article 5 above, shall be payable quarterly
in advance to the Lessor's domicile or any other location indicated by the
Lessor.

If the effective date of this lease occurs during a calendar quarter, then the
Lessee agrees to pay the Lessor an amount of rent and charges prorated on the
basis of the time remaining between the effective date and the end of the
quarter in question.

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ARTICLE 7 - INDEXING THE RENT - REVISION

The amount of the rent due by the Lessee will be updated every three years on
the anniversary date of the effective date based on the change in the
construction cost index, with the base index being 1058 (second quarter of 1998)
and the revision index is the index published on the successive revision dates.

It is specified that this clause constitutes a contractual indexing and does not
refer to the three-year revision stipulated by Articles 26 and 27 of the decree
of September 30, 1953 and that the omission of the indexing does not constitute
a waiver of indexing by the Lessor.

If the indices selected cease to be published or disappear before the expiration
of the lease, and if the National Institute of Statistics and Economic Studies
(INSEE) publishes a new index intended to replace the indices currently in
effect, the rent will be automatically indexed on the basis of these new indices
and the shift from the old indices to the new ones will be made using the
required correspondence coefficient.

If there are no statistics determined as indicated above, or in the event of a
challenge to the application of said indices, the index shall be set by an
expert named by mutual agreement of the parties or, if there is no agreement, by
order of the Chief Judge of the Lyons Regional Court ruling in an emergency
hearing at the request of the party acting first.

This expert must rule after hearing each of the parties within one month after
he is appointed.

The costs of the expert's services shall be divided equally between the parties,
unless the use of the expert was caused by the challenge of only one party, and
the expert does not uphold, even in part, the reasons for said challenge. In
this case, only the party that challenged the application of the index shall pay
the fees.

This indexing clause constitutes a determinant element in the parties' desire to
execute this Agreement, without which this lease would not have been granted.

If the indexing set forth above becomes contrary to the legislation in effect as
interpreted by the Courts, or to any law or regulation enacted thereafter, the
parties agree to replace the indexing, by mutual agreement or by an expert under
the conditions detailed above, with another formula that complies with legal
requirements and is as close as possible to the conditions set forth above.

ARTICLE 8 - GENERAL CHARGES AND CONDITIONS:

This lease is granted and accepted subject to the ordinary and legal charges and
conditions in such matters, particularly the following charges and conditions.
Any tolerance by either of the parties with regard to the other party's failure
to comply with these conditions may not be considered to generate any right
whatsoever; the party to which the obligation is owed may terminate said
tolerance at any time.

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8.1    OBLIGATIONS OF THE LESSOR

The Lessor is required to:

-      make Building C5 , which is being leased available to the Lessee, keeping
       it closed and covered and ensuring peaceful possession;

-      ensure security for the entire site, particularly regulation 273a;

-      insure the leased Building C5 against fire, explosion, water damage and
       leasing risks, excluding damages to the articles it contains;

-      assume, at its expense, the cost of the heavy repairs set forth in
       Articles 605 and 606 of the Civil Code, and the costs of any repointing
       of Building C5.

It is understood that the outcome of the work requested by the Lessee as the
result of a demand from a health authority (Drug Agency, European Central
Agency, Food and Drug Administration, etc.) is specified in Article 11 below.

8.2    OBLIGATIONS OF THE LESSEE:

8.2.1  OBLIGATIONS TO OPERATE AND FURNISH THE PREMISES:

The Lessee must personally and continuously carry out its activity in Building
C5.

It must furnish the leased Building C5, and keep it continually furnished for
the entire term of the lease with the equipment required for the production of
Lymphoglobulin and the controls, in sufficient quantity and value to meet, at
any time, the payment of the rent and the performance of the conditions of the
lease.

8.2.2  CONDITIONS OF OCCUPANCY:

The Lessee shall take the leased Building C5 as is on the date it takes
possession, without being able to demand any repair during the term of the
lease, with the exception of the heavy repairs set forth in Articles 605 and 606
of the Civil Code.

On the date Building C5 is made available, the parties shall establish a joint
inventory of the premises.

8.2.3  CONDITIONS OF POSSESSION:

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The Lessee must ensure that the tranquility and the quality of the Building C5
leased in the site of Marcy l'Etoile and the neighborhood is not disturbed in
any way because of its activity.

The Lessor shall make available to the Lessee Building C5 , which allow the
operation described in Article 3 above.

The Lessor specifies, in this respect, that it has not made any non-compete
commitment with regard to the occupants of the neighboring buildings.

The Lessee shall be personally responsible, without generating any liability or
claim for the Lessor, for all claims or actions arising from its activity in the
leased Building C5, notably with the occupants of the neighboring buildings or
third parties (in particular, the BIOMERIEUX company).

In the event that the Lessor has to pay certain sums because of the Lessee, the
Lessee must reimburse said sums to the Lessor immediately as well as all related
procedural costs and fees.

The Lessee must comply with the laws, requirements, and regulations in effect,
particularly with regard to road, sanitation, police, security, health and work
requirements.

It must pay the related fees and charges so that no claim is made against the
Lessor in respect thereof.

It must obtain all approvals and authorizations required to perform its business
and make all required declarations with the competent authorities.

The Lessee must not place or store any merchandise or articles in the corridors,
open spaces or access roads to Building C5, except in exceptional circumstances
for legitimate service needs.

The Lessee shall be personally responsible for all disturbances in possession
caused by the occupants of the neighboring buildings or third parties and shall
act directly against the authors of such disturbances, without holding the
Lessor liable.

The Lessee must notify the Lessor of any significant change in operating
conditions that might:

       -modify the general and specific requirements imposed by law on the
       Lessor's classified facilities for the entire site of Marcy l'Etoile;

       -require the performance of specific procedures with the competent
       authorities in terms of classified facilities (such as the notice of
       significant changes in operating conditions, applications for
       authorization, applications for supplemental classification, etc.)

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The Lessor must inform the Lessee of any regulatory change that could affect
Building C5.

However, it is agreed by the parties that the Lessee expressly waives the
exercise of any ordinary action because of damages and pollution that may result
from the Lessor's prudent performance of its own activity and, which would be
inherent, because of the distances between the different buildings of the Marcy
l'Etoile site, provided that the Lessee does not find it impossible to carry out
its activity because of such disturbances.

8.2.4  COMMERCIAL NAME - SIGN:

The Lessee may install and maintain any sign bearing its corporate name and/or
logo on Building C5 with the prior consent of the Lessor; it is specified that
any sign must be attached to Building C5 and may not be higher than this
Building.

In addition, the parties may decide, in the context of a decision made by the
PMC/IMTIX-SANGSTAT site Committee, to install signs for IMTIX-SANGSTAT on the
PMC site at Marcy L'Etoile.

The Lessee shall be solely responsible for accidents caused by the signs it has
installed. It must be insured in this respect and provide proof of such
insurance to the Lessor.

8.2.5  MAINTENANCE:

The Lessee shall be required to perform in Building C5, for the entire term of
the lease, at its expense, all repair and maintenance work, cleaning and,
generally, any customary repair or any customary replacement that proves
necessary; only the heavy repairs defined in Articles 605 and 606 of the Civil
Code shall be the responsibility of the Lessor.

In particular, the Lessee must maintain in good condition the locks, doors,
windows, glass, shades, electric installations, pipes, sanitary, heating, and
gas installations, conduits, and all other equipment considered to be real
property by use, etc.; such maintenance shall be paid by the Lessee and
performed under its responsibility.

In particular, the Lessee is required to subscribe to maintenance agreements for
the air conditioning and ventilation systems, a copy of which must be sent to
the Lessor at its request, and that it shall maintain in effect during the
entire term of this lease.

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Lessee shall take all useful precautions to avoid freezing all devices, conduits
and pipelines; it shall pay the costs for repairs or damages of any kind caused
by failure to observe the terms above.

It shall be responsible for all repairs , which are normally the Lessor's
responsibility, but , which are required either because of Lessee's failure to
perform the repairs for which it is responsible as described above, or because
of deterioration resulting from actions of the Lessee, the actions of its
personnel or its visitors.

It must keep the floor coverings in normal maintained condition.

8.2.6  WORK:

(a)      RELATED TO BUILDING C5

The Lessee must allow, and allow the performance of, without being able to claim
any indemnity or reduction in rent, all repointing, repair, reconstruction,
increase in height, expansion and other work in Building C5 , which the Lessor
deems necessary during the lease, subject to the application of Article 1724 of
the Civil Code; the Lessor agrees to exert its best efforts to warn the Lessee
with one month's advance notice and not to disturb the industrial activity of
the Lessee.

Pursuant to this document, if the work lasts more than 40 days, the rent shall
be reduced based on the duration of the work and the degree of loss of
possession.

In addition, the Lessee must immediately notify the Lessor in writing of any
repairs in Building C5, which it has verified are necessary, subject to being
held responsible for any further deterioration resulting from its failure to do
so.

(b)      ON THE MARCY L'ETOILE SITE

The Lessee shall tolerate, without being able to claim any indemnity or
reduction in rent from the Lessor, all work performed on the Lessor's industrial
site at Marcy L'Etoile, provided that such work does not interrupt the operation
and subject to the application of Article 1724 of the Civil Code; the Lessor
agrees to exert its best efforts to warn the Lessee with reasonable advance
notice.

The Lessee shall receive prior notice of all major work on the Marcy L'Etoile
site that may directly affect access to Building C5 for the Lessee's employees
and suppliers, and the parties shall try by mutual agreement to solve this
temporary problem and the Lessor will work to ensure that this disturbance is
the least possible.

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(c)      ON THE PUBLIC ROAD

The Lessee shall tolerate, without indemnity from the Lessor, all work that may
be executed on the public road, even if its causes a disturbance to its
operation; the Lessor agrees to make every effort so that this disturbance is
the least possible and does not impede the Lessee's activity.

8.2.7  CHANGES AND IMPROVEMENTS:

The Lessor may perform in Building C5 all equipment and installation work that
it believes necessary, provided that such work does not change the intended use
of Building C5, or injures the solidity of the building, and that it complies
with all regulations, including urban zoning regulations.

All work that includes a change in distribution, or the demolition or piercing
of walls or floors, and all work performed by the Lessee on Building C5 that may
be visible from the other buildings, must receive the prior, written
authorization of the Lessor, which shall not be withheld by the Lessor without
legitimate reasons.

In addition to the Lessor's agreement, the Lessee must make sure that it has
received all required permits and it must pay any tax that may be due.

In this case, the work must be performed at the Lessee's exclusive expense,
risks and perils and under the supervision of the Lessor's architect, whose fees
shall be paid by the Lessee.

All the work, improvements, installations and constructions, including those
that may be required by legislative or regulatory provisions, if any, made by
the Lessee during this lease shall become, at the departure of the Lessee or its
assignees, the property of the Lessor, without indemnity. The Lessor may require
restoration of Building C to its original condition in whole or in part, at the
Lessee's expense, only for work it has not authorized and that not been required
by legislative provisions.

However, it is specified, as needed, that the equipment, materials and
facilities not provided by the Lessor and not affixed and which, because of this
fact, cannot be considered as part of the building by use, shall remain the
property of the Lessee and must be removed by the Lessee when it leaves, at the
written request of the Lessor; it shall be the Lessor's responsibility to
restore Building C5 after this removal.

The Lessor may not include the work performed by the Lessee in setting the
amount of the rent for the renewed lease.

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8.2.8  INSPECTION AND SUPERVISION OF BUILDING C5:

During the entire term of the lease, the Lessor, accompanied by its architect
and all agents, may visit Building C5 once a year during business hours to
verify the condition of the Building, and shall inform the Lessee of its visit
at least seven (7) days in advance of the date planned for the inspection. The
Lessee must provide, at the Lessor's first request, all supporting documentation
requested to verify correct execution of the terms of the lease.

Access to Building C5 must always be given for verification, repairs and
maintenance of the water pipes and rainwater downpipes, gas, electricity and
heating.

8.2.9  RESPECT FOR THE MARCY L'ETOILE SITE:

Given the location of Building C5 within the Lessor's industrial site at Marcy
L'Etoile, the Lessee agrees to comply, and ensure compliance by its employees,
with the internal rules of the Marcy L'Etoile site. These internal rules may be
updated at any time by the Lessor, in which case a copy of the updated internal
rules shall be sent to the Lessee so that it is aware of the rule and informs
its employees. A change in the internal rules of the Marcy L'Etoile site may
not, however, have an impact on the distribution key for charges or on the
essential provisions of this lease.

The Lessor expressly authorizes the Lessee, its employees, its suppliers and its
visitor to use the site roads in order to access Building C5 at any time during
business hours for the site and the Lessor accepts the right-of-way.

More generally, the Lessee agrees to comply, and ensure compliance by its
employees with the requirements of the prefect's order classifying the Marcy
L'Etoile site.

For this purpose, the Lessor agrees to remit as soon as possible a copy of all
changes made to orders from the prefect that apply to the site, and of all
correspondence exchanged with competent authorities on this matter.

8.2.10 CONTRIBUTIONS, TAXES AND DUTIES:

The Lessee must pay all personal real estate taxes, rental taxes and any other
taxes specifically applicable to Lessee, related to Building C5 or related to
its business, to which tenants are or may be subject. It must repay the Lessor
on a pro-rated basis for garbage removal fees, the sewer tax, and the sweeping
tax.

It must pay all city, police and road taxes applicable to Building C5 and the
business carried out.

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8.2.11 INSURANCE:

The Lessor shall subscribe to a global insurance policy for Buildings C4 and V3a
and C5, as soon as it is available, against the risks of fire, explosion, water
damage and, generally, against the rental risks of the tenants or occupants,
with the express exclusion of the furnishings in Building C5, from a legally
solvent insurance company.

The Lessee shall inform the Lessor of any loss that occurs to Building C5,
within a reasonable period, and the Lessor shall be responsible for informing
the insurance companies concerned by the loss.

In addition, the Lessee shall obtain on its own account an insurance policy to
cover the risks of its activity and damages to its assets from a known and
legally solvent insurance company.

The Lessee must pay all premiums, portions of premiums or premium surcharges
payable because of its activity under its own policies.

The Lessee shall pay the premiums for such insurance and shall provide proof to
the Lessor, at any request from the Lessor, subject to termination of the lease.

The Lessor agrees to waive, and ensure waiver by its insurers, any action
against the Lessee and its insurers and, conversely, the Lessee and its insurers
waive any action against the Lessor whatever the reason for the damages.

8.2.12 LIABILITY, CLAIMS:

Under no circumstances shall the Lessee hold the Lessor liable for any theft or
damage that may be committed in Building C5, and it may not claim from the
Lessor any indemnity or damages or any reduction in rent in this respect, unless
such thefts or damages are the fault of the Lessor.

The Lessee may not claim any reduction in rent in the event of temporary
elimination or reduction in community services such as water, gas, electricity,
phone, or heating. The Lessor shall exert its best efforts so that the community
services so eliminated or reduced temporarily are reestablished as soon as
possible.

8.2.13 RESTORATION OF THE BUILDING:

Before transferring its facilities, the Lessee must, prior to any removal, even
partial, of the equipment, furnishings and materials, prove by presenting
documentation the payment of its contributions, both for past years and for the
current year (if necessary, the provision for the professional tax) and all
installments of its rent.

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It must also return Building C5 after completing the repairs that are its
responsibility or, if not, pay the Lessor the cost of the work necessary to
return the premises to good condition.

At the Lessor's request, it must remove, at its expense, the signs it has
installed or its predecessor has installed.

An inventory of the premises will be conducted, in the presence of the Lessee,
which has been duly called, no later than one month before the expiration of the
lease.

This inventory of the premises will include the list of the repairs to be
performed, which are the Lessee's responsibility.

The Lessee is required to perform, before its departure, all repairs for which
it is responsible. The inventory of the premises will be verified by both
parties after the Lessee leaves completely and before remittal of the keys. The
payment of the sums due by the Lessee shall be made upon the Lessor's first
request.

ARTICLE 9 - PMC/IMTIX-SANGSTAT SITE COMMITTEE

The parties have decided to create a Site Committee responsible for supervising
the application of the clauses of this lease by the two parties. The Site
Committee shall be composed of a representative of each party.

The persons appointed are as follows:

     (i)   FOR PMC:

The Director of the Marcy L'Etoile site or a delegated person.

     (ii)  FOR IMTIX-SANGSTAT

The person designated as the manager for the IMTIX-SANGSTAT Establishment on the
Marcy L'Etoile site.

In this respect, IMTIX-SANGSTAT agrees to appoint one of its employees as the
manager for Buildings C4 and C5.

Meetings of the Site Committee shall be held once every six months. However, the
members of the Site Committee may, by unanimous decision, call a meeting at any
time.

The Site Committee may be assisted by one or more experts of their choice who
work for the parties, on a case by case basis, depending on the agenda for the
meeting. In this case, the party that wants an expert to attend must inform the
other Party within a reasonable period before the scheduled date of the Site
Committee meeting in order to obtain the other party's prior agreement.

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The role of the Site Committee is to supervise the application of the clauses of
the contract and to solve any dispute concerning the application of this lease,
provided that the solution to the dispute does not have the effect of creating
an exemption from the contractual provisions already stipulated; if that is the
case, the Site Committee must refer the dispute to the legal representatives of
the two parties who shall settle the dispute.

All decisions must be adopted unanimously by the members of the Site Committee.
Under no circumstances may such decisions be considered to modify the provisions
of this contract or to increase or limit the rights and obligations of the
parties arising therefrom; such modifications may be made only by amendment to
this contract. In the exceptional event that the decisions made by the Site
Committee exceed the framework or the terms of this contract, they shall become
effective only after they are approved by the legal representatives, and an
amendment must be drafted in writing and signed by the parties to become an
integral part of this contract.

A copy of the minutes of each Site Committee meeting must be transmitted for
information purposes to each of the parties.

ARTICLE 10 - HEALTH, SAFETY, ENVIRONMENT

10.1 PRINCIPLE

The Lessee acknowledges that it has read the requirements imposed on the
industrial site of Marcy L'Etoile pursuant to Law 76-663 of July 19, 1976.

The Lessee acknowledges that it has read the prefect's authorization order of
August 24, 1994, a copy of which has been transmitted to the Lessee.

It acknowledges that it has been informed by the Lessor of the existence of a
draft prefect's order currently in preparation and the specific requirements
contained therein.

In particular, the Lessee acknowledges that it has been informed that the site
on which it conducts it activity is the subject of a single zoning order.

That, as a result of this order, the activity performed in Building C5, although
not classified, may be subject to the requirements stipulated by the prefect's
order authorizing the operations conducted by the Lessor under heading 273a of
the nomenclature of facilities classified for the protection of the environment;
the facilities and equipment, because of their proximity and related nature,
could modify the environmental impacts of the authorized facility.

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The Lessor guarantees the Lessee that the administrative authorizations in
effect on the date of this Agreement, in particular the prefect's order of
August 28, 1994, allow the Lessee to conduct the activity described in Article 3
herein and that the aforementioned proposed prefect's order does not affect this
ability.

The Lessee recognizes that the significant changes made to the conditions for
performing the activity conducted on the Marcy L'Etoile site are designed to:

-    modify the pollution emitted by the operation for which the Lessor is
     responsible;

-    require, as a result, the filing of a new application for authorization.

Given the nature of the activity, the parties recognizes that the impacts of the
Lessee's activity on the Lessor's obligations are primarily related to:

-    the limitation on water withdrawal and use;

-    the conditions for elimination of the special industrial wastes produced by
     the Lessee's activity;

-    the hazardous substances and materials used in the process to manufacture
     the products;

-    compliance with the concentration limits on residual waters stipulated by
     the prefect's authorization order.

As a result of which, the Lessee acknowledges:

-    that, based on the information provided to the Lessee by the Lessor, its
     activity generates the production of water effluents and contributes 5.3
     tons/year to the sulfate wastes currently treated by the internal
     purification facility at the Marcy L'Etoile site;

-    that any significant change in the operating conditions, even if it does
     not reach the 25% threshold, could change the operating conditions for the
     Marcy L'Etoile site and result in an obligation for the Lessor to notify
     the competent authorities of said changes.

Therefore, the Lessee:

-    agrees to use the best technologies available and similar to what the
     Lessor uses for its products at an economically acceptable costs in order
     to limit its water use and withdrawals and the concentration of its aqueous
     effluents;

-    will exert its best efforts in any event in order not to modify the
     manufacturing processes if the proposed modification were to result in a
     significant and permanent increase, with constant production, in this use
     or these effluents;

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-    undertakes to notify the Lessor of any new use of specifically regulated
     hazardous substances or preparations in significant quantities;

-    agrees to remit to the Lessor, for the purpose of elimination, the
     alcoholic and blood industrial wastes and soiled materials generated by its
     activity so that the Lessor can eliminate them or have them eliminated by
     duly authorized third parties in compliance with the laws and regulations
     in effect.

In return, the Lessor agrees to provide the Lessee with all documents (invoices
and annual certificates if requested) to prove the elimination of said wastes.
It is expressly agreed that the conditions for remittal and elimination of the
wastes and the definition of wastes shall be covered by a separate agreement.

Finally, if the Lessee wishes to obtain from the competent authorities its own
authorization to operate on the site, separate from the Lessor's authorization,
the Lessor agrees to exert its best efforts to assist the Lessee in its
procedures with said authorities and obtain the modification of the prefect's
authorization order.

10.2 RESPONSIBILITY

The Lessee agrees to pay the expenses incurred for the completion of the
additional work or facilities required because of an increase in the effluents
generated by its activity, in a proportion equal to the ratio of the volume of
effluents generated by its activity to all effluents treated by the effluent
treatment facility on the Marcy L'Etoile site. If necessary, it will consult an
expert named jointly by the parties to evaluate the polluting load of the
respective activities of PMC and IMTIX-SANGSTAT in order to obtain an equitable
division between the Lessor and the Lessee of the costs to complete the
aforementioned work.

More generally, it agrees to pay the costs required to repair or limit the
pollution generated by its activity in order to limit said pollution to a level
comparable to the pollution resulting from the Lessor's activity.

This commitment is also valid in the event the Lessor, in its capacity as
operator of the March L'Etoile site, has received formal notice to perform the
work or make the modifications required by the administration, the principal
reason for which is to repair polluting effects resulting directly from the
Lessee's activity.

The Lessee expressly acknowledges that the obligations binding on the Lessor in
its capacity as operator of the Marcy l'Etoile site with regard to the
administration shall not, under any circumstances, constitute a release from its
own responsibility for the contractual obligations defined by the parties.

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The Lessor agrees to inform the Lessee of any request or action by the
administration in a timely manner to allow the Lessee to produce the supporting
documentation and explanations it deems necessary.

The Lessee must transmit annually a report concerning the safety and environment
in Building C5 and present the results of the report to the Lessor.

The Lessor agrees to perform its obligations concerning the toxic wastes and
effluents on the entire site and not to modify the facilities for Building C5
that could modify the regulations and safety of Building C5.

10.3 RIGHT OF ACCESS

In the event that PMC has reasonable doubts about a possible major and imminent
risk to health, safety and the environment because of the actions of
IMTIX-SANGSTAT in Building C5, it is expressly stipulated that PMC may
immediately access Building C5, after attempting to contact the Lessee, in order
to make the verifications necessary, and it may use any competent administrative
authority to eliminate the risk.

10.4 AUDIT

Given the liability of PMC in respect of the environment because of the acts of
IMTIX-SANGSTAT, IMTIX-SANGSTAT shall ensure that the representatives of PMC's
environmental department may have access to Building C5 and to any document
concerning these matters, but excluding all documents containing confidential
information on the activities operated by the Lessee. In addition, the
representatives of the PMC quality department must be able to meet with the
person at IMTIX-SANGSTAT responsible for Buildings C4 and C5.

This audit option for PMC may, however, be exercised only after PMC has notified
IMTIX-SANGSTAT of the visit by its employees, 15 days in advance, and not more
than once a year, with the exception of the right of access described in Article
10.3 above.

This inspection may be postponed at the request of IMTIX-SANGSTAT in order to
limit any inconvenience, but this postponement may not exceed 15 days.

Moreover, IMTIX-SANGSTAT duly notes that representatives from the French
authorities responsible for health, safety and/or the environment may conduct
inspections in Building C5 and shall make sure that it does not prevent these
inspections in any way.

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ARTICLE 11 - WORK

Work to bring Building C5 into compliance in case of a decision from a French,
European health authority or the FDA.

All major work on Building C5 necessary after an official decision from the
French Drug Agency, a European agency or the FDA in the US must be discussed by
the parties. The parties agree to exert their best efforts to reach an agreement
on sharing the costs and planning for such work. Under no circumstances may
IMTIX-SANGSTAT perform such work without first informing PMC in writing, and PMC
will exert its best efforts to allow IMTIX-SANGSTAT to meet its regulatory
obligations.

ARTICLE 12 - DECLARATION OF THE LESSEE

The conditions for the transfer to Building C5 of the quality-control
departments currently performed by PMC under the service agreement signed
September 30, 1998 by PMC and IMTIX-SANGSTAT shall be determined by the parties
in agreement with the principles of said agreement.

ARTICLE 13 - SPECIAL CONDITIONS

13.1 TRANSFERS, SPIN-OFFS

The Lessee may not, without the written agreement of the Lessor, assign or
transfer its rights to this lease to any other person, for consideration or
without; however, it is understood that in the case of an assignment, transfer
or delegation to its Affiliates ( for the purposes of this Agreement,
"Affiliate" refers to any company or entity , which, directly or indirectly,
through one or more intermediaries, controls or is controlled by, or is under
joint control with another entity, in which the term control has the meaning
given by Article 355-1 of the Law of July 24, 1966) or in the case of a merger,
reorganization of the Lessee, or the sale by the Lessee of substantially all its
assets, no agreement from the Lessor shall be necessary, and this lease shall be
automatically transmitted, in these cases, to the Lessee's assignee or
successor.

In any event, the assignor must remain the joint guarantor of the assignee, both
for the payment of the rent, charges and fees, and for compliance with the terms
of the leases. This provision shall apply to all successive transfers. There
shall be joint and several liability among all successive Lessees for the entire
term of the lease.

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A copy of the instrument of transfer or contribution must be remitted without
charge to the Lessor, within a month after the signature.

13.2 SUB-LEASE

The Lessee may not sub-lease the Buildings, in whole or in part, nor lend them,
even without charge, without the prior express written agreement of the Lessor,
except to an Affiliate. The term of any sub-lease may not, under any
circumstance, exceed the term remaining on this lease.

As an express exception to paragraph 2, Article 22 of the Decree of September
30, 1953, it is specified that, at the expiration of the principal lease, the
Lessor shall not be required to renew partial or full sub-lease agreements. The
Lessee must be personally responsible for the eviction of any sub-lessee.

All renovation work following any sub-leases shall be the exclusive
responsibility of the Lessee, not only at the time the sub-lessee takes
possession, but also when it departs.

Any potential sub-lessee must be informed of this clause by the Lessee and under
its responsibility, prior to the signature of any sub-lease agreement. The
Lessee undertakes to ensure compliance with this clause by any sub-lessee.

ARTICLE 14 - TERMINATION CLAUSE - FINAL CLAUSES

It is expressly agreed and accepted that:

14.1  If payment of a single rent installment is not made on the due date, or if
      costs, charges or fees are not reimbursed, this lease shall be legally
      terminated at the discretion of the Lessor, without the necessity of any
      legal action, one month after an order sent to IMTIX-SANGSTAT, with a copy
      to SangStat Medical Corporation, remains unanswered, and the effect of
      this clause may not be neutralized by offers after this date. In this
      case, and if the Lessee refuses to evacuate the premises, an order issued
      by the Chief Judge of the Regional Court of Lyons will be sufficient to
      force the Lessee to evacuate the premises.

14.2  Rent and charges due and unpaid on the due date shall legally be
      increased, as penalty, by 2% per each month late as of the due date,
      without the necessity of any legal action; this indemnity must be paid at
      the same location and at the same time as the principal rent.

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14.3  In the event that, to recover its rent or fees, the Lessor is forced to
      initiate legal action or produce an order, it shall then have the right to
      an indemnity equal to ten percent of the amounts to be recovered with a
      minimum of one thousand francs to cover any and all losses and other
      damages, independently of the reimbursement of all costs and fees that it
      has paid to recover the amounts due.

14.4  In the event of significant violation of the commitments made in Articles
      3 and 10.1 of this lease, without the prior authorization of the Lessor,
      and in the event of violation of the legislative and regulatory provisions
      governing facilities classified for the protection of the environment,
      hazardous substances and preparations, and waste treatment and elimination
      duly verified by the Administration by formal notice and sanctioned by a
      final court ruling, the Lessor reserves the right to terminate this lease.

      This termination shall take effect after formal notice to correct the
      situation, sent to the Lessee by registered mail with return receipt, with
      a copy to SangStat Medical Corporation, is not followed by compliance that
      is initiated and notified to the Lessor within a period of one month.

ARTICLE 15 - CLAUSES OF THE LEASE

It is formally agreed that none of the conditions inserted in the lease may be
considered to be comminatory or stylistic but, to the contrary, must all be
fully and completely executed, without which the lease would not have been
signed.

ARTICLE 16 - FEES - RECORDING

The Lessee shall pay all fees for this Agreement, stamp taxes and, if
applicable, recording fees, as well as all fees resulting or arising therefrom.
Each of the parties shall be responsible for the fees of its counsel.

ARTICLE 17 - TRANSFERABILITY

The Lessee expressly recognizes that the Lessor has the option to transfer this
Agreement to any purchaser of Building C5, provided that such a transfer results
in no change to the provisions of this lease, without the Lessee's agreement to
such changes.

/initials                                                                PAGE 24

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ARTICLE 18 - DISPUTES

Subject to the provisions of the Decree of September 30, 1953, which assigns
exclusive jurisdiction to a national court for certain disputes, all disputes
arising from this lease, which are not amicably settled by the parties, shall be
definitively settled by arbitration in English in accordance with the
Arbitration Rules of the International Chamber of Commerce, rules that the
parties hereby declare they know, by one arbitrator if the dispute results in a
claim less than or equal to Five Hundred Thousand US Dollars (USD 500,000), or
by three arbitrators if the dispute results in a claim of more than Five Hundred
Thousand US Dollars (500,000). The site of arbitration shall be Paris, France.

Executed in as many copies as there are parties, plus one copy for recording,

In Lyons

For PASTEUR MERIEUX Serums & Vaccins                 For IMTIX-SANGSTAT

/s/ Herve Tainturier                                 /s/ Gilles Alberici
                                                          President

/initials                                                                PAGE 25

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                                   SCHEDULE 1

                              PLANS FOR BUILDING C5

/initials                                                                PAGE 26