EX. 10.19

Portions of this Exhibit have been omitted pursuant to a request for 
confidential treatment. The omitted portions, marked by * and [ ], have been 
separately filed with the Commission.

                                LICENSE AGREEMENT

This License Agreement, effective the 15th day of March, 1996, is between
Theracell, Inc., a Delaware corporation, having a principal place of business at
1505 O'Brien Drive, Suite B., Menlo Park, CA 94025 ("THERACELL"), the University
of South Florida, acting for and on behalf of the Board of Regents, a public
corporation of the State of Florida, of 4202 E. Fowler Ave., Tampa, FL 33620
("USF"), and the University of South Florida Research Foundation, Inc., a
university direct-support not for profit organization under Florida law, of 4202
E. Fowler Ave., FAO 126, Tampa, FL 33620 ("USFRF").

INTRODUCTION

WHEREAS, USF has developed, and is continuing to develop USF SERTOLI
TECHNOLOGY, as defined herein;

WHEREAS, THERACELL desires to support USF's continued development of USF SERTOLI
TECHNOLOGY, and to commercially exploit USF SERTOLI TECHNOLOGY; and

WHEREAS, THERACELL, USF, and USFRF believe it is in the public interest for USF
SERTOLI TECHNOLOGY to be further developed and commercially exploited in the
manner provided herein;

NOW, THEREFORE, in consideration of the premises and mutual covenants set forth
herein, and intending to be legally bound, the parties agree as follows:

I.       Definitions

         A.       USF Sertoli Patent Rights ("PATENT RIGHTS") shall mean:

                  1.       USF Patent Applications listed in Appendix A and any
                           successor applications, domestic or foreign resulting
                           therefrom, as well as any US or foreign patents
                           issuing therefrom.

                  2.       All subsequent USF patent applications and issued US
                           and foreign patents involving Sertoli cells filed
                           and/or issued during the term of this License
                           Agreement on which one or more of the following USF
                           researchers is also an inventor:

                           (a)      Paul R. Sanberg

                           (b)      Don F. Cameron

                           (c)      Cesario F. Borlongon



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         B.       "FIELD" shall mean extra-testicular cell and tissue
                  transplantation or administration for therapeutic medical
                  purposes.

         C.       "USF SERTOLI TECHNOLOGY" shall mean USF PATENT RIGHTS or
                  know-how related to the use of Sertoli cells in the FIELD. It
                  is further understood that "know how" means the know how of
                  USF researchers whose work in developing USF SERTOLI
                  TECHNOLOGY has been supported by funds from THERACELL or its
                  sublicensees.

         D.       "LICENSED PRODUCT" shall mean any product or process for a
                  defined medical condition covered in whole or in part by USF
                  SERTOLI TECHNOLOGY

         E.       "NET SALES" for a LICENSED PRODUCT shall mean THERACELL's and
                  its sublicensees' billings for LICENSED PRODUCT less the sum
                  of the following:

               (i)  discounts allowed in amounts customary in the trade for
                    quantity purchases, samples, prompt payments' wholesalers'
                    and distributors;

               (ii) sales, tariff duties and/or use taxes directly imposed and
                    with reference to particular sales;

               (iii) outbound transportation prepaid or allowed; and

               (iv) amounts allowed or credited on returns.

         F.       "TERRITORY" shall mean worldwide.

II.      Grant

         A.       Subject to USF's and USFRF's retained rights and covenants
                  (Section VlIl herein) USF and USFRF grant THERACELL the right
                  and license in the TERRITORY to practice under USF SERTOLI
                  TECHNOLOGY, and exclusively to the extent not prohibited by
                  patent rights of others, or retained by USF and USFRF pursuant
                  to Section VlIl herein, to make, have made, use, lease, sell,
                  export and import LICENSED PRODUCTS until the termination of
                  this Agreement.

         B.       Subject to USF's and USFRF's retained rights and covenants
                  (Section VlIl herein) THERACELL shall have the right to enter
                  into sublicensing agreements for LICENSED PRODUCTS, provided
                  however, that in no case shall a sublicense be at rates which
                  are lower than set forth herein below,


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                  except by prior written consent of USF and USFRF, which
                  consent shall not be unreasonably withheld.

                  In each sublicense agreement, THERACELL shall use its best
                  efforts to secure, as part of the sublicense terms, (i)
                  unrestricted basic research funds for USF researchers to
                  further USF SERTOLI TECHNOLOGY, (ii) USF most favored research
                  and development collaborator status (as defined in Section
                  IV.B.), and (iii) USF most favored clinical research
                  collaborator status (as defined in Section IV.C.).

                  Further, in all sublicense agreements, THERACELL shall advise
                  its sublicensee of all terms and conditions of this License
                  Agreement that could effect the sublicensee's rights in and to
                  USF Sertoli Technology.

III.     DILIGENCE

         A.       THERACELL shall use its best efforts to commercialize multiple
                  LICENSED PRODUCTS through vigorous research and development
                  and/or sublicensing efforts, and to continue active, diligent
                  marketing efforts for one or more LICENSED PRODUCTS throughout
                  the life of this agreement. In this regard, THERACELL shall:

               1.   Develop and introduce into clinical trials at least one
                    LICENSED PRODUCT within three years from the effective date
                    of this license agreement.

               2.   Continue to exploit USF SERTOLI TECHNOLOGY through its own
                    efforts and/or those of its sublicensees such that a second
                    LICENSED PRODUCT is introduced into clinical trials or
                    analogous precommercialization trials (the parties
                    understand this latter term to encompass analogous
                    regulatory trials required where a LICENSED PRODUCT is a
                    process or derived from a process in which Sertoli cells are
                    employed) within five years, and successive LICENSED
                    PRODUCTS are introduced into clinical trials or analogous
                    precommercialization trials at an average rate of one every
                    two years, until the commercialization of at least one
                    LICENSED PRODUCT.

               3.   Invest not less than $1.5 MM in connection with activities
                    described in this agreement over the course of two years
                    from the effective date of this agreement.

         B.       If THERACELL has not developed at least one LICENSED PRODUCT
                  to the stage of entering clinical trials within three years
                  from the effective date of this License Agreement, USF and
                  USFRF may convert this license

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The information below marked by * and [ ] has been omitted pursuant to a request
for confidential treatment.  The omitted portion has been separately filed with
the Commission.


                  agreement into a product specific license by terminating this
                  license as to all LICENSED PRODUCTS, except for any LICENSED
                  PRODUCTS which THERACELL or a sublicensee is then using its
                  best efforts to bring to clinical trials and for which
                  THERACELL continues to use its best efforts pursuant to this
                  Section to develop and commercialize, provided however,

                  1.       that USF and/or USFRF shall not grant licenses to
                           others (ALTERNATE LICENSEES) for remaining LICENSED
                           PRODUCTS that would compete with use of THERACELL's
                           LICENSED PRODUCTS for their defined medical
                           condition.

         C.       If THERACELL fails to maintain the development progress set
                  forth in Section III.A.2., USF and USFRF may convert this
                  license agreement into a product specific license by
                  terminating this license as to all LICENSED PRODUCTS, except
                  for any LICENSED PRODUCTS which THERACELL or a sublicensee is
                  then using its best efforts to bring to clinical trials and
                  for which THERACELL continues to use its best efforts pursuant
                  to this Section to develop and commercialize, provided
                  however,

               1.   that USF and/or USFRF shall not grant licenses to others
                    (ALTERNATE LICENSEES) for remaining LICENSED PRODUCTS that
                    would compete with use of THERACELL's LICENSED PRODUCTS for
                    their defined medical condition, and

               2.   that if THERACELL or its sublicensees have advanced at least
                    two products into clinical trials or analogous
                    precommercialization trials (The parties understand this
                    latter term to encompass analogous regulatory trials
                    required where a LICENSED PRODUCT is a process or derived
                    from a process in which Sertoli cells are employed), USFRF
                    will rebate to THERACELL up to [********] of the royalties
                    received from ALTERNATE LICENSEES, not to exceed [*******
                    ******] of NET SALES.

         D.       In the event USF and USFRF seek ALTERNATE LICENSEES, pursuant
                  to this Section III, until ALTERNATE LICENSEES for remaining
                  LICENSED PRODUCTS are found, THERACELL shall have the right to
                  negotiate with USF and USFRF to regain rights to said
                  remaining LICENSED PRODUCTS.

IV.      USF/THERACELL Research and Development Relationship

         A.       THERACELL will provide USF researchers with $110,000 per annum
                  for unrestricted basic research in furtherance of USF SERTOLI
                  TECHNOLOGY for two years beginning on the effective date of
                  this agreement. To the extent consistent with USF Rules and
                  Policy, and Florida Law, said funds


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The information below marked by * and [ ] has been omitted pursuant to a request
for confidential treatment.  The omitted portion has been separately filed with
the Commission.


                  shall be placed in a Sertoli Cell Research Fund and disbursed
                  to said researchers by mutual agreement with Dr. Paul Sanberg.

         B.       THERACELL will afford USF most favored research and
                  development collaborator status. THERACELL will on a case by
                  case basis award product research and development contracts
                  based on the ability of the contractor to deliver the required
                  services in an FDA acceptable manner, in accord with
                  development timelines, and at a competitive cost, consistent
                  with the THERACELL's obligations under Section III of this
                  agreement. To the extent that THERACELL determines that USF
                  research proposals meet these criteria, THERACELL will give
                  USF researchers priority in the awarding of such contracts.

         C.       THERACELL will afford USF most favored clinical research
                  collaborator status. THERACELL will on a case by case basis
                  award product clinical research contracts based on ability of
                  the contractor to deliver the required services in an FDA
                  acceptable manner, in accord with development times lines, and
                  at a competitive cost, consistent with THERACELL's obligations
                  under Section lIl of this agreement. To the extent that
                  THERACELL determines that USF clinical research proposals meet
                  these criteria, THERACELL will give USF clinical researchers
                  priority in the awarding of such contracts.

         D.       THERACELL will use its best efforts, consistent with economic
                  feasibility, good business practices, and its obligations
                  under Section III of this agreement to establish Research and
                  Development facility adjacent to the campus of USF for the
                  purpose, among others, of furthering the goals of this
                  agreement in collaboration with USF researchers.

V.       THERACELL Fees and Royalties

         THERACELL agrees to pay license fees and royalties (all payable to
         USFRF) as follows:

         A.       An initial License Fee of [******] to which is creditable all
                  option fees and patent attorney fees paid to USFRF by
                  THERACELL prior to February 1, 1996, in connection with USF
                  SERTOLI CELL TECHNOLOGY.

         B.       Annual License Maintenance Fees of [*****] in 1996, [*****] in
                  1997, [*****] in 1998, [*****] in 1999, and [******] for each
                  year after 1999, providing, however,

               1.   that Running Royalties due on NET SALES for each year, if
                    any, shall be creditable against the License Maintenance Fee
                    for said year.

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The information below marked by * and [ ] has been omitted pursuant to a request
for confidential treatment.  The omitted portion has been separately filed with
the Commission.


         C.       Running Royalties on NET SALES of LICENSED PRODUCTS by
                  THERACELL or its sublicensees, shall be as follows:

               1.   [******] in countries where neither patent protection for
                    LICENSED PRODUCT exists nor a competitive, Sertoli based
                    transplant product is marketed, or

               2.   [*****] in countries in which patent protection to LICENSED
                    PRODUCT exists.

                  Should THERACELL receive sublicensing royalties that are not
                  conditioned on lack of competition or existence of a patent,
                  THERACELL will rebate [********] of sublicensing royalties
                  not to exceed [***********] of NET SALES by sublicensees.

         D.       THERACELL shall rebate to USFRF [****] of the value of Initial
                  License Fees and License Maintenance Fees, or any other
                  consideration other than running royalties (as set forth
                  above), received from third parties in connection with the
                  grant of a sublicense on a LICENSED PRODUCT; provided that
                  this rebate shall not include research and development monies
                  received from third parties. It is agreed that THERACELL will
                  in good faith spend any such research and development monies
                  for that purpose, and USF's most favored research and
                  development collaborator and most favored clinical research
                  collaborator status will apply.

         E.       No multiple Royalties shall be payable to USFRF on any
                  LICENSED PRODUCT.

         F.       Royalties shall be payable on LICENSED PRODUCT for the greater
                  of 15 years from marketing in a commercial territory or until
                  the expiration (or determination of invalidity by Court of
                  last resort) of a patent covering said product in that
                  commercial territory.

VI.      Patent Prosecution

         A.       The filing, prosecution and maintenance of all PATENT RIGHTS
                  applications and patents shall be the primary responsibility
                  of USF; provided, however, that THERACELL shall have
                  reasonable opportunities to advise and consult with USF
                  thereon and shall cooperate with USF in such filing,
                  prosecution and maintenance.

         B.       Paragraph VI.A not withstanding, THERACELL may elect to assume
                  from USF primary responsibility for filing, prosecution and
                  maintenance of all PATENT RIGHTS, in the name of USF as owner
                  and assignee, and pursuant

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                  to a retainer agreement between THERACELL and outside patent
                  counsel, to be secured in consultation with USF. In the event
                  of such election, USF shall have reasonable opportunity to
                  advise THERACELL in such filing, prosecution and maintenance,
                  and THERACELL shall use its best efforts to obtain strong and
                  broad claims under PATENT RIGHTS and shall not abandon
                  prosecution of any patent application or any of the claims of
                  patent rights without written consent of USF, which consent
                  shall not be unreasonably withheld. If THERACELL decides to
                  abandon any such application or patent, it shall give USF
                  reasonable notice and opportunity to assume prosecution.

         C.       THERACELL shall assume financial responsibility for all fees
                  related to filing, prosecution and maintenance of PATENT
                  RIGHTS incurred subsequent to February 1, 1996. In the event
                  Section Vl.A. is operative, USF shall verify the accuracy of
                  attorney fees and disbursements, and submit invoices to
                  THERACELL within one month of receipt. In the event Section
                  Vl.B. is operative, attorney invoices shall be submitted
                  directly to THERACELL. In the event of a conversion of this
                  license to a product specific license, pursuant to Section
                  II.B.3, the parties, will, in good faith, negotiate an
                  equitable reduction in THERACELL's obligation to pay the fees
                  set forth in this Section Vl.C.

VlI.     Assignability

         This license may NOT be assigned to any person or entity without USF's
         and USFRF's advance written permission.

VlIl.    USF and USFRF Retained Rights and Covenants

         USF and USFRF retain the right to do all things granted to THERACELL
         under Section II, and USF and USFRF covenant not to commercially
         exploit USF Sertoli Technology unless

         (i)      authorized by this License Agreement, or

         (ii)     THERACELL becomes insolvent, or

         (iii)    anyone files a lien against this License Agreement, or

         (iv)     THERACELL takes any action, or fails to take any action, the
                  result of which gives a third party the right to file such a
                  lien, or

         (v)      THERACELL files for bankruptcy or a receiver is appointed, or


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         (vi)     THERACELL ceases to carry on its business, or

         (vii)    THERACELL materially breaches this License Agreement in a
                  manner which causes this License Agreement to terminate or
                  gives USF or USFRF the right to terminate under Section Xll.

IX.      Product Liability/Insurance

         THERACELL shall, at all times during the term of this License Agreement
         and thereafter, be solely responsible for, and defend, hold harmless
         and indemnify USF, USFRF, their trustees, officers, employees, agents
         and other representatives, against any claims and expenses, including
         legal expenses and reasonable attorneys' fees, arising out of the death
         of or injury to any person or property based upon products produced or
         developed for, or by, THERACELL, or commercially exploited by THERACELL
         or a sublicensee of THERACELL pursuant to its rights under this
         Agreement. THERACELL shall obtain and carry in full force and effect
         product liability insurance, in amounts customary in the biotech
         industry which shall protect USF, USFRF, their trustees, officers,
         employees, agents and other representatives in regard to the foregoing
         events.

X.       Record Keeping

         A.       THERACELL shall keep full, true and accurate books of account
                  containing all particulars that may be necessary for the
                  purpose of showing the amounts payable to USFRF hereunder.
                  Said books of account shall be kept at THERACELL's principal
                  place of business. Said books and the supporting data shall be
                  open at all reasonable times for five (5) years following the
                  end of the calendar year to which they pertain, to the
                  inspection of USFRF or its agents for the purpose of verifying
                  THERACELL's royalty statement of compliance in other respects
                  with this Agreement.

         B.       THERACELL, within ninety (90) days after March 31, June 30,
                  September 30 and December 31, of each year, shall deliver to
                  USFRF true and accurate reports, giving such particulars of
                  the business conducted by THERACELL and its sublicensees
                  during the preceding three-month period under this Agreement
                  as shall be pertinent to a royalty accounting hereunder. These
                  shall include at least the following:

                  (i)      number of LICENSED PRODUCTS manufactured and sold by
                           THERACELL and its sublicensees, if any,

                  (ii)     total billings for LICENSED PRODUCTS sold,

                  (iii)    deductions applicable as provided in Paragraph 
                           Section l.H.,

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               (iv) total royalty due,

               (v)  after a first sublicense is granted names and addresses of
                    all sublicensees of THERACELL (and copies of all sublicensee
                    agreements then effect), and

               (vi) if Section Vl.B. is operative progress report on patent
                    filings in each country, including the serial number, name
                    of patent application, name of inventors and status of each
                    patent application covering LICENSED PRODUCT. [If Section
                    Vl.A. is operative, USF will provide THERACELL with such
                    information at least semi-annually.]

                  With each such report submitted, THERACELL shall pay the
                  royalties, fees and any other consideration due and payable
                  under this Agreement. If no royalties, fees or other
                  consideration shall be due, THERACELL shall so report.

         C.       On or before the ninetieth (9Oth) days following the close of
                  THERACELL's fiscal year, THERACELL shall provide USF and USFRF
                  with THERACELL's certified financial statements for the
                  preceding fiscal year including, at a minimum, a Balance Sheet
                  and an Opening Statement.

         D.       The payments for royalties, fees or other consideration set
                  forth in this Agreement shall, if overdue, bear interest until
                  payment at the monthly rate of one percent (1%). The payment
                  of such interest shall not foreclose USF and USFRF from
                  exercising any other rights either may have as a consequence
                  of the lateness of any payment.

         E.       THERACELL hereby agrees that it shall not sell, transfer,
                  export or reexport any LICENSED PRODUCTS or related
                  information in any form, or any direct products of such
                  information, except in compliance with all applicable laws,
                  including the export laws of any U.S. government agency and
                  any regulations thereunder, and will not sell, transfer,
                  export or reexport any such LICENSED PRODUCTS or information
                  to any persons or any entities with regard to which there
                  exist grounds to suspect or believe that they are violating
                  such laws. THERACELL shall be solely responsible for obtaining
                  all licenses, permits or authorizations required from the U.S.
                  and any other government for any such export or reexport. To
                  the extent not inconsistent with this Agreement, USF and USFRF
                  agree to provide THERACELL with such assistance as it may
                  reasonably request in obtaining such licenses, permits or
                  authorization.


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Xl.      Non-Use of Names

THERACELL shall not use the names of the USF or USFRF, nor any adaptation of
either, in any advertising, promotional or sales literature without prior
written consent obtained from USF and/or USFRF in each case, except that
THERACELL may state that it is licensed under one or more of the patents and/or
applications comprising the Patent Rights. The parties agree to issue a mutually
agreed press release on or after the Effective Date.

Xll.     Term and Termination

         A.       Unless sooner terminated as provided herein, this License
                  Agreement will expire with respect to a given LICENSED PRODUCT
                  on the later of the date of the last to expire of the PATENT
                  RIGHTS or fifteen (15) years from the first bona fide
                  commercial sale of said LICENSED PRODUCT. Upon such expiration
                  of this License Agreement, THERACELL shall have a fully
                  paid-up worldwide right and license to continue to
                  commercially exploit said LICENSED PRODUCT.

         B.       If THERACELL assigns this License Agreement without USF's and
                  USFRF's written permission, in violation of Section Vll, this
                  License Agreement shall terminate automatically.

         C.       If THERACELL shall cease to carry on its business, this
                  License Agreement shall terminate upon notice by USF and/or
                  USFRF.

         D.       In the event either party files for bankruptcy or a receiver
                  is appointed, this License Agreement may immediately
                  thereafter be terminated at the option of the other party.

         E.       Should THERACELL fail to pay the royalties, fees and/or other
                  consideration due and payable hereunder, USFRF and/or USF
                  shall have the right to terminate this License Agreement on
                  forty-five (45) days notice, unless THERACELL shall pay,
                  within the forty-five (45) day period, all such royalties,
                  fees and other consideration, and interest due and payable.
                  Upon the expiration of the forty-five (45) day period, if
                  THERACELL shall not have paid all such royalties, fees and
                  other consideration, and interest due and payable, the rights,
                  privileges and license granted hereunder shall terminate.

         F.       Upon any material breach or default this License Agreement by
                  THERACELL. other than those occurrences set out hereinabove
                  which shall always take precedence in that order over any
                  material breach or default referred to in this Section, USFRF
                  and/or USF shall have the right to terminate this License
                  Agreement and the rights, privileges and license granted
                  hereunder upon thirty (30) days' written notice to THERACELL.

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                  Such termination shall become effective unless (i) Licensee
                  shall have cured any such breach or default prior to the
                  expiration of thirty (30) days from the date THERACELL
                  receives notice of the breach or default, or (ii) THERACELL
                  shall have demonstrated substantial efforts to cure such
                  breach or default, which efforts shall be reasonably
                  satisfactory to USF and/or USFRF.

         G.       THERACELL shall have the right to terminate this License
                  Agreement at any time on six (6) months' written notice to
                  USFRF and USF, and upon payment of all amounts due USFRF
                  through the effective date of the termination.

         H.       Upon termination of this License Agreement for any reason,
                  nothing herein shall be construed to release either party from
                  any obligation that matured prior to the effective date of
                  such termination. THERACELL and any sublicensee thereof may,
                  however, after the effective date of such termination, sell
                  all LICENSED PRODUCTS, and complete LICENSED PRODUCTS in the
                  process of manufacture at the time of such termination and
                  sell the same, provided that THERACELL shall pay to USF and/or
                  USFRF the royalties thereon as required by Article IV of this
                  License Agreement and shall submit the reports required by
                  Article V hereof on the sales of the LICENSED PRODUCTS.

               1.   Upon termination of this License Agreement for any reason,
                    any sublicensee not then in default under its sublicense
                    agreement with THERACELL shall automatically have a license
                    under this License Agreement as a direct THERACELL of USF
                    and/or USFRF, on economic terms no less favorable than those
                    set forth in the sublicense agreement, and otherwise with
                    the same rights and obligations as THERACELL hereunder,
                    provided, however, that such automatic license is granted
                    only, to the extent that it does not conflict with any other
                    rights lawfully granted to anyone else, and further provided
                    that such automatic license shall terminate unless
                    sublicensee, within thirty (30) days from notice by USF
                    and/or USFRF that this License Agreement has terminated,
                    shall:

               (i)  state to USF and USFRF in writing that to the best of its
                    knowledge and belief, it is capable of performing to such an
                    automatic sublicense;

               (ii) pay any royalties, fees and other consideration (including
                    interest) due and payable, or cure any such breach or
                    default in any manner which preserves the value to USFRF and
                    USF of this License Agreement, or demonstrate substantial
                    efforts

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                    to cure such breach or default, which efforts shall be
                    reasonably satisfactory to USFRF and USF;

                    or the license hereunder to sublicense shall terminate.

               J.   Upon termination of this Agreement for any reason, all
                    intellectual property rights licensed hereunder, including
                    without limitation all PATENT RIGHTS and all USF Sertoli
                    Technology shall revert to USF and/or USFRF and THERACELL
                    shall have no further right to or continuing interest
                    herein.

XlIl.    Payments, Notices and Other Communications

Any payment, notice or other communication pursuant to this License Agreement
shall be sufficiently made or given on the date of mailing if sent to such party
by certified first class mail or air courier, postage prepaid, addressed to it
at its address below or it shall designate by written notice given to the other
party:

                  In the case of USFRF:

                          USF Research Foundation, Inc.
                                 P. O. Box 30445
                              Tampa, FL 33620-3044

                  In the case of THERACELL:

                                    Theracell, Inc.
                           1505 O'Brien Drive, Ste. B
                              Menlo Park, CA 94025

                  All Payments to:

                          USF Research Foundation, Inc.
                                 P.O. Box 20445
                              Tampa, FL 33620-30440

                  In the case of USF:

                          Director, Sponsored Research
                          4202 E. Fowler Ave., FAO 126
                                 Tampa, FL 33620


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XIV.     Infringement

The parties consider infringement (either of the Patent Rights or of a third
party patent) to be a different matter from the patent and other legal fees
referred to in this License Agreement, and the parties therefore agree that it
is in their mutual interests to confer when a question of infringement (either
of the Patent Rights or of a third party patent) arises before taking legal
action which may result in substantial expense. It is the intent of the parties
to evaluate the infringement-related situations on a case-by-case basis in order
to determine the best course of action.

XV.      Miscellaneous Provisions

         A.       Each party represents and warrants that it has the authority
                  to enter into this License Agreement and that the execution,
                  delivery and performance of this Agreement do not conflict
                  with any agreement or understanding, either written or oral,
                  to which it is a party or to which it is otherwise bound.

         B.       This License Agreement shall be construed, governed,
                  interpreted and applied in accordance with the laws of the
                  State of Florida, U.S.A., except that questions affecting the
                  construction and effect of any Patent Rights shall be
                  determined by the law of the country in which the patent was
                  granted.

         C.       The parties hereto acknowledge that this License Agreement
                  sets forth the entire agreement and understanding of the
                  parties hereto as to the subject matter hereof, and shall not
                  be subject to any change or modification except by the
                  execution of a written instrument subscribed to by the parties
                  hereto.

         D.       If any term, covenant or condition of this License Agreement
                  or the application thereof to any party or circumstance shall,
                  to any extent be held to be invalid or unenforceable,

                  (i)      the remainder of this License Agreement, or the
                           application of such term, covenant or condition to
                           the parties or circumstances other than those as to
                           which it is held invalid or unenforceable, shall not
                           be affected thereby and each term, covenant or
                           condition of this Agreement shall be valid and be
                           enforced to the fullest extent permitted by law; and

                  (ii)     the parties hereto covenant and agree to renegotiate
                           any such term, covenant or application thereof in
                           good faith in order to provide a reasonably
                           acceptable alternative to the term, covenant or
                           condition of this License Agreement or the
                           application thereof that is invalid or unenforceable,


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                  it being the intent of the parties that the basic purposes of
                  this License Agreement are to be effectuated.

         E.       THERACELL agrees to mark the containers or packages of
                  LICENSED PRODUCTS sold in the United States with all
                  applicable United States patent numbers. All LICENSED PRODUCTS
                  shipped to or sold in other countries shall be marked in such
                  a manner as to confirm with the patent laws and practice of
                  the country of manufacture or sale.

         F.       The failure of any party to assert a right hereunder or to
                  insist upon compliance with any term or condition of this
                  License Agreement shall not constitute a waiver of that right
                  or excuse a similar subsequent failure to perform any such
                  term of condition by the other party.

         G.       EXCEPT AS OTHERWISE EXPRESSLY SET FORTH IN THIS LICENSE
                  AGREEMENT, USF and/or USFRF MAKE NO REPRESENTATION AND EXTEND
                  NO WARRANTIES OF ANY KIND, EITHER EXPRESS OF IMPLIED,
                  INCLUDING BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY,
                  FITNESS FOR A PARTICULAR PURPOSE, NON INFRINGEMENT, AND
                  VALIDITY OF PATENT RIGHTS CLAIMS, ISSUED OR PENDING.



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IN WITNESS WHEREOF, the parties have hereunto set their hands and seals and duly
executed this License Agreement the day and year set forth below.

UNIVERSITY OF SOUTH FLORIDA
RESEARCH FOUNDATION, INC.

By  /S/ KENNETH G. PRESTON                      /S/ DEANNA BONDOC
    ----------------------------                ---------------------------
    Kenneth G. Preston                          Witness
    Executive Director
    Date:

UNIVERSITY OF SOUTH FLORIDA

By  /S/ GEORGE R. NEWKOME                      /S/ AMY COMBAST
    ----------------------------               ----------------------------
    George R. Newkome                          Witness
    Vice President
    Date:


THERACELL INC.

By  /S/ RICHARD ALLEN                          /S/ DEANNA BONDOC
    -----------------------------              ---------------------------- 
    Richard Allen, Ph.D.                       Witness
    President and CEO
    Date:



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                    APPENDIX A TO LICENSE AGREEMENT EFFECTIVE
                                  MARCH 15,1996
                        BETWEEN USF, USFRF, AND THERACELL

Patent Applications

TITLE:            Purified and Isolated Sertoli Cell Aggregate
Filing Date:      4/20/95
Serial No.:       08/425,868
Inventors:        Richard Heller, Don F. Cameron, Paul R. Sanberg, and Mark J.
                  Jaroszeski

TITLE:            Sertoli Cells as Transplantation Facilitor for Cell
                  Transplantation
Filing Date:      3/13/95
Serial No.:       08/402,387
Inventors:        Paul R. Sanberg, Don F. Cameron, Cesario V. Borlongan, and
                  Richard Heller (note: based upon information from Inventors,
                  inventorship may need to be changed to delete Richard Heller)

TITLE:            Sertoli Cells as Neurorecovery Inducing Cells for
                  Neurodegenerative Disorders Filing Date: 3/13/95
Serial No.:       08/402,389
Inventors:        Paul R. Sanberg, Don F. Cameron, and Cesario V. Borlongan


TITLE:            Method and Media for Enhancing Cryopreservation of Cells
Filing Date:      3/12/96
Serial No.:       08/615,039
Inventors:        Don F. Cameron, Paul R. Sanberg, Cesario V. Borlongan and
                  Samuel Saporta



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PCT/CIP Applications

TITLE:            Sertoli Cells as Neurorecovery Inducing Cells for
                  Neurodegenerative Disorders - CIP which was filed through the
                  PCT designating the US
Filing Date:      3/12/96
Serial No.:
Inventors:        Paul R. Sanberg, Don F. Cameron; and Cesario V. Borlongan


TITLE:            Sertoli Cells as Transplantation Facilitator for Cell
                  Transplantation - CIP which was filed through the PCT
                  designating the US
Filing Date:      3/12/96
Serial No.:
Inventors:        Paul R. Sanberg, Don F. Cameron, Cesario V. Borlongan, and
                  Richard Heller (note: based upon information from Inventors,
                  inventorship may need to be changed to delete Richard Heller)






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