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                                                                  EXHIBIT 10.38

                                  GUARANTY OF LEASE


     Guaranty (this "Guaranty"), dated December 26, 1996 made by Genzyme 
Transgenics Corporation, a Delaware corporation, that has its executive 
office and principal place of business at 25 Birch Street, Milford, MA 01757, 
(the "Guarantor") in favor of FINOVA Technology Finance, Inc. ("FINOVA"), of 
Farmington, Connecticut (hereinafter called, with its successors and assigns, 
including the assignee from time to time of its rights under this Guaranty, 
the "Beneficiary"). 

                                       RECITALS


     The Guarantor is a stockholder of or is otherwise financially interested 
in TSI Corporation (the "Lessee"). The Guarantor has previously entered into 
a guaranty of the obligations of the Lessee under the Master Equipment Lease 
Agreement between Lessee, as lessee, and FINOVA (formerly named Financing For 
Science International, Inc.) as lessor that was limited to $2,000,000.00, to 
induce FINOVA to undertake additional leasing to the Lessee, and for Ten 
Dollars ($10) and other good and valuable consideration, the receipt of which 
by the Guarantor is hereby acknowledged, the Guarantor hereby covenants and 
agrees as follows: 

     Section 1. Guaranty.  The Guarantor unconditionally and irrevocably 
guarantees to the Beneficiary: 

          (a)  the prompt and full payment of any and all amounts payable by 
the Lessee under the Lease including, but not limited to, payment of Basic 
Rent and Additional Rent under and as defined by the Lease and of other debts 
and obligations of the Lessee to the Beneficiary under the Lease including 
for taxes, due to loss or damage of the Equipment and for default by the 
Lessee under the Lease, as and when the same shall be due and payable 
(whether on a date fixed for payment, by acceleration, upon any renewal, 
expiration, termination or cancellation of the Lease Term (as defined in the 
Lease), or at any other time) in accordance with the provisions of the Lease, 
and any amounts payable to the Beneficiary by reason of any progress payments 
to suppliers of the Equipment together with any time charges or interest on 
the progress payments; and 

          (b)  the prompt, full and faithful performance and discharge of all 
obligations, undertakings (which term as used in this Guaranty shall include, 
without limitation, covenants, commitments and duties to indemnify) and 
liabilities of the Lessee under the Lease, whether or not liquidated in 
amount, in accordance with the terms thereof.

     If the Lessee shall fail to pay any such amount when and as the same 
shall be due in accordance with the terms of the Lease, or if the Lessee 
fails to perform and discharge any such obligation, undertaking or liability 
in accordance with the terms of the Lease, the Guarantor will forthwith pay 
such amount or perform and discharge such obligation, undertaking or 
liability, 

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as the case may be, not paid, performed or discharged by the Lessee, and will 
further pay any and all damages that may be payable by the Lessee in 
consequence thereof and all reasonable expenses, including attorneys' fees, 
that are incurred by the Beneficiary in enforcing such obligations and 
liabilities of the Lessee. In addition, the Guarantor shall pay all 
reasonable expenses, including attorneys' fees, that may be incurred by the 
Beneficiary in enforcing the covenants and agreements of the Guarantor in 
this Guaranty. The Guarantor further guarantees that all payments made by the 
Lessee to the Beneficiary with respect to any liabilities hereby guaranteed 
will, when made, be final and agrees that if any such payment is recovered 
from, or repaid by, the Beneficiary in whole or in part in any bankruptcy, 
insolvency or other proceeding instituted by or against the Lessee, this 
Guaranty shall continue to be fully applicable to such liabilities to the 
same extent as though the payment so recovered or repaid had never been made.

     Section 2.  Unconditional Character of Obligations of Guarantor.  
Nothing shall discharge or satisfy the liability of the Guarantor hereunder 
except the full payment and performance of all of the Lessee's obligations, 
undertakings and liabilities under the Lease, and the obligations and 
commitments of the Guarantor hereunder shall be absolute, irrevocable and 
unconditional, irrespective of, and shall not be altered or affected by, the 
validity, regularity or enforceability of any provision of the Lease, the 
recovery of any judgment against any person or any action to enforce the 
same, any failure or delay in the enforcement of the obligations of the 
Lessee under the Lease, or any other circumstance which might otherwise 
constitute a legal or equitable defense or discharge of a guarantor or 
surety, or which might otherwise limit recourse against the Guarantor by the 
Beneficiary. The Guarantor authorizes the Beneficiary, in its sole 
discretion, at any time after the occurrence of an Event of Default under the 
Lease, to proceed under this Guaranty and against any property securing the 
obligations of the Guarantor hereunder for the full amount of the Lessee's 
obligations to the Beneficiary, with or without the Beneficiary's taking any 
action against the Lessee or any other obligor with respect to the Lessee's 
obligations under the Lease, and whether or not the Beneficiary has proceeded 
against any property securing the obligations of Lessee or of the Guarantor 
hereunder or of any other such obligor. 

     Section 3.  Right to Deal with Lessee.  At any time and from time to 
time, without terminating, affecting or impairing the validity of this 
Guaranty or the obligations of the Guarantor hereunder, the Beneficiary may 
deal with the Lessee in the same manner and as fully as if this Guaranty did 
not exist and shall be entitled, among other things, to grant to the Lessee 
such extension or extensions of time to perform, or to waive any obligation 
of the Lessee to perform, any act or acts as may seem advisable to the 
Beneficiary. 

     Section 4.  Continuing Guaranty.  This Guaranty is a continuing guaranty 
of all existing and future obligations and liabilities of the Lessee to the 
Beneficiary and shall remain in full force and effect irrespective of any 
interruption in the business relations of the Lessee with the Beneficiary. 

     Section 5.  Guaranty Not Affected by Acts of Lessee or Assignments of 
Beneficiary.  The validity of this Guaranty, the obligations of the Guarantor 
hereunder and the rights of the Beneficiary to enforce this Guaranty by 
proceedings, whether by action at law, suit in equity or otherwise, shall not 
be terminated, affected or impaired by reason of any filing by or against the 


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Lessee of a petition under any bankruptcy or reorganization law or for the 
appointment of a receiver, trustee or liquidator of the Lessee, or any 
application of the Lessee for a moratorium or for an arrangement with the 
Lessee's creditors or a material part thereof, or the making by the Lessee of 
a general assignment for the benefit of creditors, or the taking by the 
Lessee of any action for the purpose of effecting any of the foregoing, or 
any limitations placed on the liability of the Lessee in any bankruptcy, 
reorganization, moratorium or other proceedings, or any assignment by the 
Beneficiary of any interest in the Lease or this Guaranty or any change in 
the identity, or the ownership of capital stock, of the Lessee. 

     Section 6.  Guaranty Not Affected by Amendments, etc.  The validity of 
this Guaranty and the obligations of the Guarantor hereunder shall not be 
terminated, affected or impaired by reason of (a) any compromise, alteration, 
release, renewal, extension, modification, amendment, termination or other 
change of, or any waiver, consent or other action or omission or failure to 
act in respect of, any of the terms, covenants or conditions of the Lease, 
any of the transactions contemplated thereby, or any of the documents 
referred to therein, (b) any assignment by any person of any interest under 
the Lease, any of the transactions contemplated thereby, or any of the 
documents referred to therein, or (c) the exercise by any person of, or any 
waiver of or failure to enforce, any of the rights or remedies provided in 
the Lease or otherwise. 

     Section 7.  Guaranty Not Affected by Other Agreements.  The covenants 
and agreements of the Guarantor in this Guaranty shall not be terminated, 
affected or impaired by reason of the existence or the terms or provisions of 
any other guaranty or guarantees to FINOVA (or its assigns) of the 
obligations of the Lessee under the Lease by the Guarantor or other agreement 
or agreements to which the Lessee or the Guarantor shall be a party and, 
notwithstanding any such guarantees, agreements, terms or provisions, the 
obligations of the Guarantor shall be as herein expressed. 

     Section 8.  Certain Rights and Powers of Beneficiary.  The Beneficiary 
may proceed to protect and enforce any or all of its rights under this 
Guaranty by suit in equity, action at law or by other appropriate 
proceedings, whether for the specific performance of any covenants or 
agreements contained in this Guaranty, or otherwise, or to take any action 
authorized or permitted under applicable law, and shall be entitled to 
require and enforce the performance of all acts and things required to be 
performed hereunder by the Guarantor. Each and every remedy shall, to the 
extent permitted by law, be cumulative and shall be in addition to any other 
remedy given hereunder or now or hereafter existing at law or in equity.

     Section 9.  Subordination of Guarantor.  With respect to all amounts 
paid by the Guarantor pursuant to this Guaranty, until the Beneficiary shall 
have received full and complete payment and performance of all present and 
future sums, undertakings, duties, liabilities, and obligations of the Lessee 
to the Beneficiary, the Guarantor expressly waives and disclaims any right 
to, and agrees not to seek or claim, contribution, indemnification or 
reimbursement from the Lessee, or right of recourse to any security for the 
debts and obligations of the Lessee to the Beneficiary. Any and all present 
and future debts and obligations of, and other payments from, Lessee to the 
Guarantor payable in money or monies, securities, other property, or any 
combination thereof, including, without limitation, payments on any note of 
Lessee at any time held by or payable to the order of the Guarantor, and any 
distribution by Lessee of earnings and profits or of return of capital are 
hereby waived and postponed in favor of and subordinated to 


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the full payment and performance of all present and future debts and 
obligations of the Lessee to the Beneficiary. At any time or times that any 
such subordinated properties or payments are received by the Guarantor, they 
shall be received in trust for the Beneficiary and promptly delivered to the 
Beneficiary. The Guarantor shall cooperate with the Beneficiary to enable the 
Beneficiary to receive the benefits of the subordination effected by this 
Guaranty.

     Section 10.  Insolvency.  If the Lessee or the Guarantor should at any 
time become insolvent or make a general assignment for the benefit of 
creditors, or if any petition in bankruptcy or any insolvency or 
reorganization proceedings shall be filed or commenced by, against or in 
respect of the Lessee or the Guarantor, any and all obligations of the 
Guarantor hereunder shall, at the Beneficiary's option, forthwith become due 
and payable without notice or demand. The Guarantor hereby grants power of 
attorney to FINOVA to file claims against the Lessee in respect of the debts, 
obligations and other payments subordinated by this Guaranty at any time that 
the Lessee is insolvent or has made a general assignment for the benefit of 
creditors, or if any petition in bankruptcy or any insolvency or 
reorganization proceedings shall be filed or commenced by, against or in 
respect of the Lessee. The Guarantor shall not file any claims in such 
proceedings except with the advance written approval of the Beneficiary.

     Section 11.  Information on Guarantor.  The Guarantor agrees to furnish 
upon the request of FINOVA or its assign such financial, business and 
operational information concerning the Guarantor as FINOVA or its assign may 
from time to time reasonably request including copies of the tax returns of 
the Guarantor. Additionally, the Guarantor shall furnish to FINOVA and its 
assigns so long as there are any obligations guaranteed hereby in existence 
and without notice or demand therefor two complete copies of (i) the 
Guarantor's quarterly interim financial statements within 45 days of the 
close of each of its first three fiscal quarters of every year certified by 
its chief financial officer and (ii) the Guarantor's annual financial 
statements within 90 days of the close of each of its fiscal years reported 
on by its independent accountants without material adverse qualification or 
comment. All such financial statements shall be prepared in accordance with 
generally accepted accounting principles consistently applied, and shall 
accurately and completely present the Guarantor's financial condition and the 
results of its operations as of the dates of and for the periods covered by 
such statements. Throughout the term of the Lease, the Guarantor shall 
promptly furnish to the Beneficiary copies of any definitive proxy statements 
or reports on Form 10-K, 10-Q, or 8-K or similar forms, or amendments 
thereof, that it files with the SEC or any government agency. 

     Section 12.  Representations and Warranties of Guarantor.  The Guarantor 
represents and warrants (and if requested by the Beneficiary, will provide an 
opinion of counsel and other supporting documents to the effect) that as of 
the date hereof: (i) the Guarantor is a corporation duly organized, validly 
existing and in good standing under the laws of the jurisdiction of its 
organization, and is qualified and in good standing to do business wherever 
necessary to carry on its present business and operations; (ii) the Guarantor 
has the corporate power to enter into this Guaranty and to pay and perform 
its obligations hereunder; (iii) this Guaranty has been duly authorized, 
executed and delivered by the Guarantor, and constitutes the valid, legal and 
binding obligation of the Guarantor enforceable in accordance with its terms; 
(iv) no vote or consent of, or notice to, the holders of any class of stock 
of the Guarantor is required, or if required, such vote or consent has been 
obtained or given, to authorize the execution, delivery and performance of 
this Guaranty; (v) neither the execution and delivery by the Guarantor of 
this Guaranty nor 


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compliance by the Guarantor with the provisions hereof conflicts with or 
results in a breach of any of the provisions of the Certificate of 
Incorporation or By-laws of the Guarantor or of any applicable law, judgment, 
order, writ, injunction, decree, award, rule or regulation of any court, 
administrative agency or other governmental authority, or of any indenture, 
mortgage, deed of trust, agreement or other instrument of any nature to which 
the Guarantor is a party or by which it is bound, or constitutes a default 
under any thereof or will result in the creation of any lien, charge, 
security interest or other encumbrance in favor of any one other than the 
Beneficiary upon any of the assets of the Guarantor; (vi) no consent, 
approval, withholding of objection or other authorization of or by any court, 
administrative agency, other governmental authority or any other person is 
required, except such consents, approvals or other authorizations which have 
been duly obtained and are in full force and effect, in connection with the 
execution, delivery or performance by the Guarantor of this Guaranty; (vii) 
there are no actions, suits or proceedings pending, or, to the knowledge of 
the Guarantor, threatened, in any court or before any administrative agency 
or other governmental authority against or affecting the Guarantor, which, if 
adversely decided would or could, individually or in the aggregate, 
materially and adversely affect the business, operations, property or 
financial condition of the Guarantor or the ability of the Guarantor to 
perform any of its obligations under this Guaranty; (viii) no Event of 
Default or event or condition which upon the passage of time, the giving of 
notice, or both, would constitute an Event of Default under the Lease, exists 
or is continuing; (ix) the financial statements of the Guarantor furnished to 
the Beneficiary have been prepared in conformity with generally accepted 
accounting principles consistently applied and accurately and completely 
present the financial condition and the results of operations of the 
Guarantor as of the dates of and for the periods covered by such statements; 
and (x) there has been no material adverse change in the Guarantor's 
financial or other condition, business, operations, properties, assets or 
prospects since the date of the most recent financial statements of the 
Guarantor furnished to the Beneficiary.

     Section 13.  Commercial Transaction.  The Guarantor acknowledges that 
the Transaction of which this Guaranty is a part is a commercial transaction, 
and the Guarantor hereby waives such rights as the Guarantor may have to 
notice and/or hearing under any applicable federal or state laws pertaining 
to the exercise by the Beneficiary of such rights as the Beneficiary may 
have, including but not limited to the right to deprive the Guarantor of or 
affect the use or possession or enjoyment of any of the Guarantor's property 
prior to the rendition of a final judgment against the Guarantor. 

     Section 14.  Applicable Law.  This Guaranty shall be governed by and 
construed in accordance with Connecticut law. 

     Section 15.  Venue and Personal Jurisdiction.  The Guarantor hereby 
consents and agrees that any action or proceeding arising directly, 
indirectly or otherwise from this Guaranty shall be held within the State of 
Connecticut and the Guarantor hereby consents and submits to such 
jurisdiction and venue within the State of Connecticut and agrees that 
mailing to Guarantor's last known address by registered mail of any process 
shall constitute lawful process.

     Section 16.  Waiver of Jury.  The Guarantor and the Beneficiary waive 
any and all right to trial by jury in any action or proceeding relating in 
any way to this Guaranty.


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     Section 17.  Failure or Indulgence not Waiver; Additional Rights of 
Beneficiary.  (a) No failure to exercise, and no delay in exercising, any 
right, power or remedy hereunder on the part of the Beneficiary shall operate 
as a waiver thereof, nor shall any single or partial exercise of any right, 
power or remedy preclude any other or further exercise thereof or the 
exercise of any other right, power or remedy. Any waiver by the Beneficiary 
of any right under this Guaranty must be in writing to be effective and shall 
not be construed as a waiver of any subsequent breach thereof. 

     (b)  The Beneficiary shall be entitled to injunctive relief in case of 
the violation or attempted or threatened violation of any of the provisions 
hereof, to a decree compelling performance of any of the provisions hereof, 
and to any other remedies allowed in law or in equity. 

     Section 18.  Acknowledgment: Other Waivers.  The Guarantor acknowledges 
that its officers and directors have read and understand the provisions of 
this Guaranty and the Lease, and that the Beneficiary has made no 
representation or warranty to them or to the Guarantor in respect of any 
transaction contemplated hereby or thereby. The Guarantor hereby expressly 
waives notice from the Beneficiary of its acceptance or reliance on this 
Guaranty. The Guarantor also waives presentment and protest of any 
instrument, and notice thereof, notice of default or dishonor, and all other 
notices to which the Guarantor might otherwise be entitled. 

     Section 19.  Notices.  All notices, requests, demands and other 
communications under this Guaranty or in respect hereof shall be in writing 
and shall be hand delivered or mailed by first-class certified mail, postage 
prepaid, to the parties hereto addressed as follows: 

   if to the Guarantor, to:   Genzyme Transgenics Corporation
                              25 Birch Street
                              Milford, MA 01757

   if to FINOVA, to:          FINOVA Technology Finance, Inc.
                              10 Waterside Drive
                              Farmington, Connecticut 06032-3065

or to such other address as to a party hereto as such party shall designate 
in a written notice to the other.

     Section 20.  Further Assurances.  The Guarantor hereby agrees to execute 
and deliver all such instruments and take such action as may from time to 
time be reasonably requested by the Beneficiary in order fully to effectuate 
the purposes of this Guaranty. 

     Section 21.  Amendments.  The terms of this Guaranty may not be altered, 
modified, amended, supplemented or terminated in any manner whatsoever except 
by written instrument signed by each party hereto.

     Section 22.  Counterparts.  This Guaranty may be executed, accepted and 
delivered in any number of counterparts, each of which shall be an original, 
but such counterparts shall together constitute one and the same instrument.


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     Section 23.  Successors and Assigns.  This Guaranty shall be binding 
upon and shall inure to the benefit of the guarantor, the Beneficiary and 
their respective heirs, executors, administrators, representatives, 
successors and assigns. For the purposes of this Guaranty, "Lessee" shall 
mean and include any successor of the Lessee including the Lessee as a debtor 
in possession or any representative of the Lessee under the provisions of any 
state or federal law governing bankruptcy, insolvency, receivership or 
reorganization.

     IN WITNESS WHEREOF, the parties have executed this Guaranty, as of the 
day and year first above written.

Attest:                       GENZYME TRANSGENICS CORPORATION

(SEAL)


By:/s/ Lynnette C.Fallon           By /s/ John B. Green          
   ----------------------------       ----------------------------
Secretary/Assistant Secretary      Its Vice President


Personally appeared John B. Green, Vice President of Genzyme Transgenics 
Corporation signer and sealer of the foregoing instrument, and acknowledged 
the same to be the free act and deed of said corporation executed pursuant to 
a resolution of its Board of Directors, before me the 4th day of February, 
1997.


                              /s/ Elaine B. Spinale                   
                              ----------------------------------------
                              Notary Public
                              My Commission Expires: 11/17/2000




Accepted this 18th day of
March 1997 at
Farmington, Connecticut


FINOVA TECHNOLOGY FINANCE, INC. 


By: /s/ Linda Moschitto
    ---------------------------


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