LICENSE AND SUPPLY AGREEMENT

EFFECTIVE DATE:  March 21, 1995

PARTIES:

     Cistron Biotechnology, Inc.
     Box 2004
     10 Bloomfield Avenue
     Pine Brook, New Jersey, USA 07058               ("CISTRON") 

     Research and Diagnostic Systems, Inc.
     614 McKinley Place NE
     Minneapolis, Minnesota, USA 55413                    ("R&D")

RECITALS:

     A.   CISTRON has an exclusive, worldwide license from the New England 
Medical Center Hospitals, Inc., Tufts University, Massachusetts Institute of 
Technology and Wellesley College (the "Institutions") to make, use and sell, 
and to sublicense to others, products utilizing the human interleukin-1 beta 
("IL-1b"), which is the subject of patents owned by the Institutions, and to 
make, use and sell products incorporating the inventions claimed in such 
patents and related technology (the "License Agreement"). 

     B.   CISTRON has developed and is selling an IL-1b precursor assay and 
IL-1b mature protein in the research market under the terms of the License 
Agreement.

     C.   R&D desires to purchase the IL-1b precursor research assay product 
and IL-1b mature protein for resale pursuant to the terms and conditions of
this Agreement.

AGREEMENT:

     In consideration of the rights, obligations and mutual premises set forth 
herein, CISTRON and R&D, intending to be bound thereby, agree as follows:


                     Article 1.  Definitions

     The following terms as used in this Agreement shall have meanings set 
forth in the Article.

     1.1  Territory.  "TERRITORY" shall mean the research market worldwide.

     1.2  Precursor Kit(s).  "PRECURSOR KIT(S)" shall mean the following 
finished, but unlabelled, components of CISTRON's IL-1b human precursor assay 
(catalog 03-1000).  

          a.   1 Monoclonal antibody coated 96 well strip microtiter plate, 
     foil sealed

          b.   1 Vial of recombinant IL-1b precursor standard (lyophilized, 
     50ng/ML after reconstituting)

          c.   1 Vial of IL-1b precursor polyclonal antibody (lyophilized, 
     11 mL after reconstituting)

          d.   1 Bottle of conjugate (liquid concentrate, 0.5mL)

     1.3  IL-1b Protein.  "IL-1b PROTEIN" shall mean CISTRON's IL-1b mature
protein (catalog 01-1600).

     1.4  Confidential Information.  "CONFIDENTIAL INFORMATION" shall mean
any proprietary information or materials belonging to the disclosing party 
(whether or not patentable) including, but not limited to, formulations, 
techniques, methodology, equipment, data, reports, including any negative 
developments, know-how, sources of supply, patent positioning, consultants and 
business plans and purchase forecasts which are communicated to, learned by, or
otherwise acquired by the party receiving such information or materials during 
or in the course of this Agreement.

Notwithstanding the foregoing, CONFIDENTIAL INFORMATION shall not include any
information which (a) is or becomes part of the public domain through no act or
omission on the part of the receiving party, (b) is disclosed to a third party 
by the disclosing party without restriction on such third party, (c) is in the 
receiving party's possession at or prior to the time of disclosure under this 
Agreement and the receiving party is under no prior obligation of 
confidentiality with respect thereto, (d) is disclosed to the receiving party 
by a third party having no obligation of confidentiality with respect thereto, 
(e) is independently developed by the receiving party, or (f) is released from 
confidential treatment by written consent of the disclosing party.

     1.5  IL-1b Patents.  "IL-1b PATENTS" shall mean all United States and 
foreign patents and patent applications and any divisions, continuations, 
continuations in part, reissues, reexaminations, renewals and extensions 
thereof, and all pending applications therefor: (a) which are set forth on 
Appendix A, or (b) which claim inventions that are related to IL-1b or 
derivatives, mutants, variants, fragments or chemical analogues thereof, and 
which are conceived or reduced to practice in whole or in part by 
(i) employees, agents or contractors of CISTRON during the AGREEMENT PERIOD or 
(ii) which are licensed to CISTRON, or (c) which are derived in whole or in 
part from material, information or data proprietary to CISTRON and provided by 
CISTRON to R&D and as reduced to writing by either party within thirty (30) 
days of transfer and the receipt of which is acknowledged in writing by R&D.

     1.6  Agreement Period.  "AGREEMENT PERIOD" shall mean the time commencing 
with the execution of this Agreement and extending until the last to expire of
the IL-1b PATENTS as regards the sale and use of the IL-1b PROTEIN and for a 
period of seven (7) years as regards the PRECURSOR KIT.

     1.7  Affiliate.  "AFFILIATE" shall mean any division of R&D and any wholly
owned subsidiary of Techne Corporation, R&D's parent corporation.


                  Article 2.  Supply Agreement

     2.1  Purchase and Supply.  During the AGREEMENT PERIOD, R&D agrees to
purchase PRECURSOR KITS and IL-1b PROTEIN from CISTRON for resale in the
TERRITORY under R&D's name and CISTRON agrees to manufacture and supply to R&D
PRECURSOR KITS and IL-1b PROTEIN on a non-exclusive basis under the terms and
conditions set forth in this Agreement. 

     2.2  Restrictions.  Except as provided in paragraph 2.11 and paragraph 
4.1, R&D agrees (a) to no longer sell its IL-1b gene or gene fragments (catalog
BBG 2 and BBG 25), its IL-1b protein (catalog 201-LB), or supply its IL-1b 
protein as a standard in its IL-1b assay kit(s), (b) to purchase all of its 
requirements for IL-1b PROTEIN only from CISTRON and (c) to utilize only the 
IL-1b PROTEIN obtained from CISTRON as the standard in its IL-1b assay kit(s).

     2.3  License Fee.  R&D agrees to pay to CISTRON immediately following the
execution of this Agreement by both parties, a nonrefundable payment of One 
Million Dollars ($1,000,000) as payment in full for the right and license 
granted by CISTRON to R&D to purchase, use and resell in the TERRITORY the 
PRECURSOR KITS and IL-1b PROTEIN (either alone or packaged with other 
components, e.g. in an assay kit) on a non-exclusive basis only on the terms 
and conditions set forth in this Agreement.

     2.4  Prices.

          a.   PRECURSOR KITS.  CISTRON agrees to manufacture and supply
     PRECURSOR KITS to R&D at the following prices:

     Quarterly R&D Purchases       Sale Price/Kit to R&D

     less than 125 kits       $225.00 each plus freight and insurance
     125 - 175                $195.00 each plus freight and insurance
     176 - 250                $186.00 each plus freight and insurance
     251 +                    $164.00 each plus freight and insurance

          b.   IL-1b PROTEIN.  CISTRON agrees to manufacture and supply IL-1b
     PROTEIN to R&D at the following prices:

     Bulk Order by R&D             Sale Price to R&D

     1 mg to 10 mg            $3,500.00/mg plus freight and insurance
     11 mg to 15 mg           $3,000.00/mg plus freight and insurance
     16 mg +                  $2,500.00/mg plus freight and insurance
     
     2.5  Purchase Orders/Forecasts.  R&D will provide CISTRON with its 
estimated purchase order requirements on a two calendar quarter rolling basis.
The first calendar quarter (or portion thereof) of such estimate shall 
constitute a firm purchase order, the second calendar quarter of such estimate 
shall be for information purposes only.  R&D will provide the first such 
rolling estimate to CISTRON upon execution of this Agreement and thereafter no 
later than thirty (30) days prior to the start of each calendar quarter.

     2.6  Increased Forecasts.  Should R&D increase a calendar quarter's 
purchase orders by twenty percent (20%) or more from that quarter's prior 
estimate, CISTRON will use its best efforts to fill such increased order.  
However, R&D may not refuse acceptance of shipment from CISTRON of quantities 
equating to eighty percent (80%) of that quarter's prior estimate; provided, 
however, R&D shall have the right to manufacture or have manufactured the 
twenty percent (20%) shortfall of IL-1b PROTEIN in accordance with the
provisions of paragraphs 2.11 and 4.1.

     2.7  Initial PRECURSOR KITS Order.  R&D will place an order for a minimum 
of one hundred (100) PRECURSOR KITS on the Effective Date of this Agreement.

     2.8  Acceptance of Orders/Title.  All orders from R&D will be subject to
acceptance by CISTRON.  All purchases pursuant to orders by R&D shall be, at 
CISTRON's option, F.O.B. Pine Brook, New Jersey, USA or other place of 
manufacture.  Title to, and risk of loss of and damage to, any shipments of the
PRECURSOR KITS or IL-1b PROTEIN shall pass to R&D when such Products are 
delivered at any F.O.B. location to a carrier designated by R&D in its 
purchase order.  If R&D has failed to specify a carrier in its purchase order, 
CISTRON may use a carrier of its choice.

     2.9  Shipment.  CISTRON will ship R&D the quantity of PRECURSOR KITS and
IL-1b PROTEIN ordered in a quarterly purchase order within forty-five (45) days
of receipt of such purchase order and will invoice R&D on the date of shipment.
R&D shall pay each invoice within thirty (30) days of the date of the invoice.
CISTRON will, whenever possible, ship complete orders; however, should CISTRON 
be unable to ship a complete order, CISTRON will so notify R&D.  R&D may accept
or refuse partial shipments at its discretion, but may not refuse acceptance of
shipments that comprise not less than eighty percent (80%) of a complete order.

     2.10 Quality Control Testing.  CISTRON will perform quality control 
testing on each lot of PRECURSOR KITS and IL-1b PROTEIN and provide such 
manufacturing and quality control information to R&D as may be mutually agreed 
as necessary with each new production lot.  R&D agrees to keep such information
confidential pursuant to the terms of paragraph 6.2 of this Agreement and to 
restrict its use of such information solely to the sale and use of the 
PRECURSOR KITS and IL-1b PROTEIN.

     2.11 Acceptance.  R&D shall perform in-house testing, at its own expense, 
as it deems appropriate upon receipt of each product shipment from CISTRON, R&D
will report any product performance deficiencies or quantity discrepancies that
R&D may discover to CISTRON within fifteen (15) days of receipt.  Failure to 
report any product deficiencies or discrepancies within fifteen (15) days of 
the receipt of each product shipment shall constitute acceptance of the 
shipment.  If R&D notifies CISTRON within fifteen (15) days of its receipt of 
PRECURSOR KITS or IL-1b PROTEIN that the Product fails to meet specification, 
such non-conforming Products which are due to a defect of one or more of the 
components supplied by CISTRON shall be replaced by CISTRON as soon as 
reasonably possible thereafter.  If CISTRON is unable to supply IL-1b PROTEIN 
that meets quality specifications or not in sufficient quantity to fill R&D's 
order, R&D may substitute its IL-1b protein only until such time as CISTRON is 
able to supply sufficient conforming product.

     2.12 Completion of PRECURSOR KITS.  R&D will provide buffers for each
PRECURSOR KIT, label the PRECURSOR KITS and components as R&D products and
provide product literature for inclusion of each PRECURSOR KIT.

     2.13 Other Terms and Conditions.  Any term or condition in an invoice or 
other document used by CISTRON which is in addition to or different than the 
terms of this Agreement shall be deemed inapplicable.


                     Article 3.  Warranties

     3.1  Corporate Authority.  CISTRON and R&D each represents and warrants 
to the other that:

          a.   it is a corporation, duly organized, validly existing and in 
     good standing under the laws of the state of its incorporation;

          b.   it has taken all necessary action on its part that may be 
     required under the laws of its state of incorporation and under its 
     certificate of incorporation and its bylaws to authorize the execution, 
     delivery and performance of this Agreement; and

          c.   this Agreement constitutes the valid and legally binding 
     obligation of such party, enforceable against it in accordance with its 
     terms.

     3.2  License Agreement.  CISTRON represents and warrants to R&D that it 
has the exclusive, worldwide license from the Institutions to make, use and 
sell, and to sublicense to others, products utilizing the IL-1b and to make, 
use and sell products incorporating the inventions claimed in the IL-1b PATENTS
and related technology under the terms of the License Agreement. 

     3.3  Product Warranty.  CISTRON warrants (a) the merchantability of
PRECURSOR KITS and IL-1b PROTEIN only for use as research tools and in the case
of the PRECURSOR KIT, only when used in conformance with CISTRON's PRECURSOR 
KIT protocol, and (b) that the IL-1b PROTEIN and the PRECURSOR KIT will meet 
the written specifications provided by CISTRON and reviewed by R&D.  CISTRON 
MAKES NO WARRANTY OF MERCHANTABILITY OR PERFORMANCE AFTER EXPIRATION OF THE 
FIFTEEN (15) DAY PERIOD DESCRIBED IN PARAGRAPH 2.11 ABOVE.

     3.4  DISCLAIMER OF WARRANTIES.  THE WARRANTIES SET FORTH IN
THIS ARTICLE 3 ARE THE ONLY WARRANTIES MADE BY THE PARTIES AND
ARE EXPRESSLY IN LIEU OF ANY AND ALL OTHER WARRANTIES EXPRESSED
OR IMPLIED, INCLUDING, WITHOUT LIMITATION, ANY AND ALL WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 
NOTWITHSTANDING ANYTHING STATED HEREIN TO THE CONTRARY, IN NO
EVENT SHALL EITHER PARTY BE LIABLE TO THE OTHER PARTY OR TO ANY
DISTRIBUTEE OF THE OTHER PARTY OR ANYONE ELSE IN PRIVITY WITH THE
OTHER PARTY FOR ANY SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES
REGARDLESS OF WHETHER OR NOT THE FIRST PARTY HAS BEEN APPRISED OF
THE POSSIBILITY THEREOF.


                  Article 4.  Guaranteed Supply

     4.1  Uninterrupted Supply.  CISTRON agrees to sell to R&D during the
AGREEMENT PERIOD under the price, payment and purchase terms of Article 2 of 
this Agreement, R&D's requirements of the IL-1b PROTEIN.  If CISTRON is unable 
to provide R&D with its requirements of the IL-1b PROTEIN for whatever reason, 
including, without limitation, events of force majeure and financial problems, 
R&D shall have the right to manufacture or have manufactured its IL-1b protein 
(catalog 201-LB) in sufficient quantities to fulfill R&D's requirements as 
described in its purchase order delivered to CISTRON and subject to CISTRON'S 
right to resume supply in accordance with the provisions of Section 2.11 
herein.  


                Article 5.  Term and Termination

     5.1  Term.  Unless earlier terminated pursuant to paragraphs 5.2, 5.3 or 
5.4, the provisions of this Agreement relating to the IL-1b PROTEIN will expire
upon the expiration of the last to expire of the IL-1b PATENTs and the 
provisions of this Agreement relating to the PRECURSOR KIT will expire seven 
(7) years from the Effective Date of this Agreement.  For purposes of this 
paragraph, "expire" shall mean expiration, abandonment, cancellation, 
disclaimer, award to another in an interference proceeding, or declaration 
of invalidity or unenforceability by a court or other authority of competent 
jurisdiction from which no further appeal has or can be taken.

     5.2  Termination For Breach.  Upon material breach of this Agreement by 
either party and in the event the breach is not cured within forty-five (45) 
days after delivery of written notice to the defaulting party by the other 
party, in addition to any other remedy it may have, the notifying party at its 
sole option may terminate this Agreement by delivery of an additional 
termination notice to the other party at the end of such forty-five (45) day
period.

     5.3  Insolvency.  This Agreement may be terminated by one party if the 
other party becomes insolvent, is unable to pay its debts as they mature, makes
an assignment for the benefit of its creditors, files a petition for protection
under any bankruptcy law, has an involuntary petition for bankruptcy filed 
against it, or applies for the appointment of a receiver or trustee for 
substantially all of its property or assets or permits the appointment of any 
such receiver or trustee who is not discharged within a period of thirty (30) 
days after such appointment.

     5.4  Infringement by PRECURSOR KIT.  The portions of this Agreement
pertaining to the PRECURSOR KIT may be terminated by either party upon learning
of the existence of a third party patent which, in the opinion of competent 
legal counsel, is infringed by the sale of the PRECURSOR KIT.

     5.5  Post Termination Rights.  Upon any termination of this Agreement, R&D
will be entitled to use and sell any completed inventory of PRECURSOR KITS 
and/or IL-1b PROTEIN covered by this Agreement which remain on hand as of the 
date of the termination, so long as R&D pays to CISTRON the amount applicable 
to the purchase of such inventory in accordance with the terms and conditions 
as set forth in this Agreement.  The above described rights and obligations of 
R&D and the rights and obligations of the parties under Section 6.2, Article 7 
and Section 8.2 of this Agreement are the only rights and obligations of either
party which shall survive termination of this Agreement.

     5.6  Notification of Breach of License Agreement.  CISTRON shall notify 
R&D immediately if Cistron receives any notice of breach or termination of 
CISTRON's license from the Institutions.  In such case if CISTRON cannot or 
will not cure such breach, CISTRON shall allow R&D to cure such breach and 
deduct the cost thereof from the payments due to CISTRON under Article 2 of 
this Agreement.


            Article 6  Publicity and Confidentiality

     6.1  Public Disclosure.  The parties shall mutually agree upon the wording
of the initial press release regarding this Agreement.  Neither party shall use
the name of the other party in any form of advertising or promotion, without 
the express prior written approval of the other party.

     6.2  Confidentiality.

          a.   Obligations.  Except as provided in paragraph 6.2.b. below, for 
     a period of five (5) years from the termination date of this Agreement, 
     the receiving party will maintain any and all of the CONFIDENTIAL 
     INFORMATION received from the other party, in confidence, will not use 
     same for its own benefit except as expressly provided in this Agreement, 
     and will not release or disclose any tangible or intangible component 
     thereof to any third party without first receiving the prior written 
     consent of the disclosing party to said release or disclosure.

          b.   Exceptions.  The provisions of paragraph 6.2.a. notwithstanding,
     a receiving party may disclose CONFIDENTIAL INFORMATION of the other party
     to its own affiliates or in the event of a disclosure compelled by a court
     of competent jurisdiction.  In addition, a receiving party may disclose 
     CONFIDENTIAL INFORMATION of the other party in confidence to any third 
     party who has a need to know such CONFIDENTIAL INFORMATION for the purpose
     of this Agreement; provided that the receiving party will first notify the
     other party of the identity of such third party and that such disclosure 
     will be made under the provisions of a written confidential disclosure 
     agreement which is binding upon such third party to the same obligations 
     of confidentiality under which the receiving party is bound to the 
     disclosing party by the terms of this Agreement.  R&D need not notify 
     CISTRON before disclosing any CONFIDENTIAL INFORMATION of CISTRON to any
     AFFILIATE.


                   Article 7.  Indemnification

     7.1  Defense By CISTRON.  In the event that litigation against R&D and/or 
its AFFILIATES, officers, directors, employees or successors and assigns, is 
initiated by a third party charging R&D with infringement of a patent as a 
result of R&D's resale of IL-1b PROTEIN licensed under this Agreement, R&D 
shall promptly notify CISTRON in writing thereof.  CISTRON agrees to intervene 
on R&D's behalf and to take over the sole defense of the action at CISTRON's 
expense.  In such event, R&D agrees to cooperate with CISTRON in all respects 
including making available relevant records, papers and the like and providing
its employees to testify as requested.  CISTRON will reimburse R&D for the 
expenses incurred in providing such assistance.

     7.2  Settlement.  No settlement, consent judgment or other voluntary final
disposition of the suit which adversely affects the IL-1b PATENTS may be 
entered into without the consent of CISTRON.

     7.3  Payment By CISTRON.  In the event of a final judgment in any suit 
in which a court of competent jurisdiction, from which there is not appeal, 
rules that R&D's resale of IL-1b PROTEIN licensed under this Agreement has 
infringed on a third-party's patent requiring R&D to pay damages or a royalty 
to a third party, or in the event of a settlement of such suit requiring 
damages or royalty payments to be made, CISTRON will pay such damages or 
royalty payments on R&D's behalf.


                 Article 8.  General Provisions

     8.1  Relationship.  The relationship between CISTRON and R&D is that of
independent contractors.  CISTRON and R&D are not joint venturers, partners, 
principal and agent, master and servant, employer and employee, and have no 
relationship other than as independent contracting partners.  CISTRON will have
no power to bind or obligate R&D in any manner.  Likewise, R&D will have no 
power to bind or obligate CISTRON in any manner.

     8.2  Arbitration. 

          a.   Submission of Dispute.  Any dispute, claim or controversy 
     arising out of or relating to this Agreement (a "Dispute") shall be 
     resolved by binding arbitration conducted pursuant to the provisions of 
     this Agreement and the commercial arbitration rules of the American 
     Arbitration Association ("AAA"), unless such AAA rules are inconsistent 
     with the provisions of this Agreement.  Even though the arbitrator(s) 
     shall apply the AAA rules, the arbitration shall not be conducted by the 
     AAA.  Either party may commence arbitration proceedings by delivery of 
     written notice to the other party describing the Dispute ("Arbitration 
     Notice").

          b.   Appointment of Arbitrator(s).  The case shall be submitted to a 
     single arbitrator who shall be a retired state or federal judge or an 
     attorney who has practiced business litigation for at least ten (10) 
     years.  Each party shall submit a list of three (3) arbitrators to the 
     other party within ten (10) days after delivery of the Arbitration Notice.
     From the combined list, the parties shall mutually agree on the 
     arbitrator.  Should the parties be unable to agree on the choice of an 
     arbitrator within thirty (30) days after delivery of the Arbitration 
     Notice, the arbitration shall be conducted by a panel of three (3) 
     arbitrators.  Each party shall choose one arbitrator within ten (10) after
     the expiration of the above thirty (30) day period and the two selected 
     shall choose a third arbitrator within five (5) days after their 
     appointment.

          d.   Location of Arbitration.  The site of the arbitration shall be 
     in the state of New York.  The exact location within New York shall be 
     designated by the arbitrator(s).

          e.   Interim Remedies.  Either party may apply to any court having
     jurisdiction hereof and seek injunctive relief so as to maintain the 
     status quo until such time as the arbitration award is rendered or the 
     Dispute is otherwise resolved.

          f.   Costs and Fees.  Each party shall be responsible for its own 
     costs and expenses of the arbitration and the costs and fees of the 
     arbitrator(s) shall be borne equally between the parties, unless the 
     arbitrator(s) indicate otherwise in the award.
  
          g.   Binding Effect.  The decision and award rendered by the 
     arbitrator will be final and binding.  Judgment upon the award may be 
     entered in any court having jurisdiction thereof.

     8.3  Entire Agreement.  This Agreement sets forth the entire agreement and
understanding between the parties as to the subject matter thereof and 
supersedes all prior oral or written agreements to this respect.  This 
Agreement shall be binding upon and inure to the benefit of the successors and 
assigns of each party. 

     8.4  Modifications and Waivers.  No purported amendment, modification or 
waiver of any provision hereof shall be binding unless set forth in a writing 
signed by both parties (in the case of amendments and modifications) or by the 
party to be charged thereby (in the case of waivers).  Any waiver shall be 
limited to the circumstance or event specifically referenced in the written 
waiver document and shall not be deemed a waiver of any other term of this 
Agreement or of the same circumstance or event upon any recurrence thereof.

     8.5  Governing Law.  This Agreement will be construed and enforced in
accordance with the laws of the State of New York without reference to its 
choice of law principles.

     8.6  Headings.  The headings in this Agreement have been inserted for the
convenience of the reference only and are not intended to limit or expand on 
the meaning of the language contained in the particular article or paragraph.

     8.7  Notices.    Any notice or other communication required or permitted 
under this Agreement shall be made in writing and shall be deemed to have been 
delivered upon the earlier of (i) when received, if personally delivered, 
(ii) the next business day after delivery if delivered by telecopy or telex, 
(iii) the next business day after placement with a reputable overnight delivery
service for next day delivery, or (iv) five (5) business days after depositing 
in the U.S. mails for delivery by certified or registered mail, return receipt
requested, postage prepaid and addressed to the appropriate party at the 
following address:

     To R&D:        R&D Systems, Inc.
                    614 McKinley Place NE
                    Minneapolis, Minnesota USA 55413
                    ATTN:  Roger C. Lucas, Ph.D.
                            or Senior Executive Officer/Biotechnology

     Copy to:       Fredrikson & Byron, P.A.
                    1100 International Center
                    900 Second Avenue South
                    Minneapolis, Minnesota USA 55402
                    ATTN:  Timothy M. Heaney, Esq.


     To CISTRON:    Cistron Biotechnology, Inc.
                    Box 2004
                    10 Bloomfield Avenue
                    Pine Brook, New Jersey USA 07058
                    ATTN:  Bruce C. Galton

     Copy to:       Epstein Becker & Green, P.C.
                    250 Park Avenue
                    New York, New York 10177-0077
                    ATTN:  Seth I. Truwit, Esq.

Addresses may be changed by delivery of notice to the other parties pursuant to
the terms of this paragraph.  Any notice of change of address shall not be 
effective until actually received by the addressee.

     8.8  Injunctive Relief.  The parties acknowledge and agree that a breach 
of any of the terms and conditions of this Agreement, including the provisions 
relating to confidentiality, may cause irreparable injury to the non-breaching 
party and, according, that the prevailing party may seek and obtain in any 
arbitration, in addition to damages, any and all available equitable remedies, 
including, without limitation, specific performance and injunctive relief.

     8.9  Force Majeure.  Each party hereto will be excused from performance 
for failure or delay in meeting any obligations hereunder due to Acts of God, 
acts of war, fire, flood, embargo, riots or revolution, provided that such 
excused performance will last only for so long as that party's performance is 
reasonably prevented by such force majeure.  The party affected by such force 
majeure is to use its best efforts to mitigate any damage thus occasioned.

     8.10 Severability.  The provisions of this Agreement are severable and 
in the event that any provision of this Agreement shall be determined to be 
invalid or unenforceable, such invalidity or unenforceability shall not in any 
way affect the validity or enforceability of the remaining provisions hereof.

        IN WITNESS WHEREOF, the parties have executed this Agreement as of the 
date first written above.


Accepted and Agreed to:

CISTRON BIOTECHNOLOGY, INC.             RESEARCH AND DIAGNOSTIC
                                              SYSTEMS, INC.



By                                   By                        
    ------------------                   -----------------
    Bruce C. Galton                      Roger C. Lucas  
TITLE:  President & COO              TITLE: Executive V.P.                  

DATE:  March 31, 1995                DATE:  March 31, 1995              

                            

                           APPENDIX A

                          IL-1b PATENTS


                         U.S. Patent No. 4,762,914
                         U.S. Patent No. 4,766,069
                         U.S. Patent No. 5,001,057
                         U.S. Patent No. 5,077,219


                      Foreign Equivalents, including

                         EPO Publication No. 0161901B1