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                                                                  Exhibit 10.69

                       MASTER LOAN AND SECURITY AGREEMENT


                           THIS AGREEMENT dated as of September 30, 1999, is
made by The Immune Response Corporation ("IMNR"), a Delaware corporation having
its principal place of business and chief executive office at 5935 Darwin Court,
Carlsbad, California 92008, and I.R.C Inc. ("IRC"), a Delaware corporation,
having its principal place of business and chief executive office at 5935 Darwin
Court, Carlsbad, California 92008, (individually and collectively, the
"Borrower") in favor of Transamerica Business Credit Corporation, a Delaware
corporation (the "Lender"), having its principal office at Riverway II, West
Office Tower, 9399 West Higgins Road, Rosemont, Illinois 60018.

                  WHEREAS, the Borrower has requested that the Lender make Loans
to it from time to time; and

                  WHEREAS, the Lender has agreed to make such Loans on the terms
and conditions of this Agreement.

                  NOW, THEREFORE, in consideration of the premises and to induce
the Lender to extend credit, the Borrower hereby agrees with the Lender as
follows:

                  SECTION  1.       DEFINITIONS.

                  As used herein, the following terms shall have the following
meanings, and shall be equally applicable to both the singular and plural forms
of the terms defined:

AGREEMENT shall mean this Master Loan and Security Agreement together with all
schedules and exhibits hereto, as amended, supplemented, or otherwise modified
from time to time.

APPLICABLE LAW shall mean the laws of the State of Illinois (or any other
jurisdiction whose laws are mandatorily applicable notwithstanding the parties'
choice of Illinois law) or the laws of the United States of America, whichever
laws allow the greater interest, as such laws now exist or may be changed or
amended or come into effect in the future.

BUSINESS DAY shall mean any day other than a Saturday, Sunday, or public holiday
or the equivalent for banks in New York City.

CODE shall have the meaning specified in Section 8(d).

COLLATERAL shall have the meaning specified in Section 2.

COLLATERAL ACCESS AGREEMENT shall mean any landlord waiver, mortgagee waiver,
bailee letter, or similar acknowledgement of any warehouseman or processor in
possession of any Equipment.

EFFECTIVE DATE shall mean the date on which all of
the conditions specified in Section 3.3 shall have been satisfied.

EQUIPMENT shall have the meaning specified in Section 2.

EVENT OF DEFAULT shall mean any event specified in Section 7.

FINANCIAL STATEMENTS shall have the meaning specified in Section 6.1.

GAAP shall mean generally accepted accounting principles in the United States of
America, as in effect from time to time.


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LOANS shall mean the loans and financial accommodations made by the Lender to
the Borrower in accordance with the terms of this Agreement and the Notes.

LOAN DOCUMENTS shall mean, collectively, this Agreement, the Notes, and all
other present and future documents, agreements, certificates, instruments, and
opinions delivered by the Borrower under, in connection with or relating to this
Agreement, or any other present or future instrument or agreement between Lender
and Borrower, as each of the same may be amended, modified, extended, restated
or supplemented from time to time.

MATERIAL ADVERSE CHANGE shall mean, with respect to any Person, a material
adverse change in the business, prospects, operations, results of operations,
assets, liabilities, or condition (financial or otherwise) of such Person taken
as a whole.

MATERIAL ADVERSE EFFECT shall mean, with respect to any Person, a material
adverse effect on the business, prospects, operations, results of operations,
assets, liabilities, or condition (financial or otherwise) of such Person taken
as a whole.

NOTE shall mean each Promissory Note made by the Borrower in favor of the
Lender, as amended, supplemented, or otherwise modified from time to time, in
each case substantially in the form of Exhibit B.

OBLIGATIONS shall mean and include all loans (including the Loans), advances,
debts, liabilities, obligations, covenants and duties owing by Borrower to
Lender of any kind or nature, present or future, whether or not evidenced by the
Note or any note, guaranty or other instrument, whether or not arising under or
in connection with, this Agreement, any other Loan Document or any other present
or future instrument or agreement, whether or not for the payment of money,
whether arising by reason of an extension of credit, opening, guaranteeing or
confirming of a letter of credit, loan, guaranty, indemnification or in any
other manner, whether direct or indirect (including those acquired by
assignment, purchase, discount or otherwise), whether absolute or contingent,
due or to become due, now due or hereafter arising and however acquired
(including without limitation all loans previously made by Lender to Borrower).
The term includes, without limitation, all interest (including interest accruing
on or after a bankruptcy, whether or not an allowed claim), charges, expenses,
commitment, facility, closing and collateral management fees, letter of credit
fees, reasonable attorneys' fees, taxes and any other sum properly chargeable to
Borrower under this Agreement, the other Loan Documents or any other present or
future agreement between Lender and Borrower.

PERMITTED LIENS shall mean such of the following as to which no enforcement,
collection, execution, levy, or foreclosure proceeding shall have been
commenced: (a) liens for taxes, assessments, and other governmental charges or
levies or the claims or demands of landlords, carriers, warehousemen, mechanics,
laborers, materialmen, and other like Persons arising by operation of law in the
ordinary course of business for sums which are not yet due and payable, or liens
which are being contested in good faith by appropriate proceedings diligently
conducted and with respect to which adequate reserves are maintained to the
extent required by GAAP; (b) deposits or pledges to secure the payment of
worker's compensation, unemployment insurance, or other social security benefits
or obligations, public or statutory obligations, surety or appeal bonds, bid or
performance bonds, or other obligations of a like nature incurred in the
ordinary course of business; (c) licenses, restrictions, or covenants for or on
the use of the Equipment which do not materially impair either the use of the
Equipment in the operation of the business of the Borrower or the value of the
Equipment; and (d) attachment or judgment liens that do not constitute an Event
of Default.

PERSON shall mean any individual, sole proprietorship, partnership, limited
liability partnership, joint venture, trust, unincorporated organization,
association, corporation, limited liability company, institution, entity, party,
or government (including any division, agency, or department thereof), and the
successors, heirs, and assigns of each.

SCHEDULE shall mean each Schedule in the form of Schedule A hereto delivered by
the Borrower to the Lender from time to time.

SOLVENT means, with respect to any Person, that as of the date as to which such
Person's solvency is measured:


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                  (a)      the fair saleable value of its assets is in excess of
the total amount of its liabilities (including contingent liabilities as valued
in accordance with GAAP) as they become absolute and matured;

                  (b)      it has sufficient capital to conduct its business;
and

                  (c)      it is able generally to meet its debts as they
mature.

TAXES shall have the meaning specified in Section 5.5.

                  SECTION 2. CREATION OF SECURITY INTEREST; COLLATERAL. The
Borrower hereby assigns and grants to the Lender a continuing general, first
priority lien on, and security interest in, all the Borrower's right, title, and
interest in and to the collateral described in the next sentence (the
"Collateral") to secure the payment and performance of all the Obligations. The
Collateral consists of all equipment set forth on all the Schedules delivered
from time to time under the terms of this Agreement (the "Equipment"), together
with all present and future additions, parts, accessories, attachments,
substitutions, repairs, improvements, and replacements thereof or thereto, and
any and all proceeds thereof, including, without limitation, proceeds of
insurance and all manuals, blueprints, know-how, warranties, and records in
connection therewith, all rights against suppliers, warrantors, manufacturers,
sellers, or others in connection therewith, and together with all substitutes
for any of the foregoing.

                  SECTION 3. THE CREDIT FACILITY.

                           SECTION 3.1. BORROWINGS. Each Loan shall be in an
amount not less than $50,000, and in no event shall the sum of the aggregate
Loans made exceed the amount of the Lender's written commitment to the Borrower
in effect from time to time. Notwithstanding anything herein to the contrary,
the Lender shall be obligated to make the initial Loan and each other Loan only
after the Lender, in its sole discretion, determines that the applicable
conditions for borrowing contained in Sections 3.3 and 3.4 are satisfied. The
timing and financial scope of Lender's obligation to make Loans hereunder are
limited as set forth in a commitment letter executed by Lender and Borrower,
dated as of September 23, 1999 and attached hereto as EXHIBIT A (the "Commitment
Letter").

                           SECTION 3.2. APPLICATION OF PROCEEDS. The Borrower
shall not directly or indirectly use any proceeds of the Loans, or cause,
assist, suffer, or permit the use of any proceeds of the Loans, for any purpose
other than for the purchase, acquisition, installation, or upgrading of
Equipment or the reimbursement of the Borrower for its purchase, acquisition,
installation, or upgrading of Equipment.

                           SECTION  3.3.    CONDITIONS TO INITIAL LOAN.

                  (a)      The obligation of the Lender to make the initial Loan
is subject to the Lender's receipt of the following, each dated the date of the
initial Loan or as of an earlier date acceptable to the Lender, in form and
substance satisfactory to the Lender and its counsel:

                           (i)      completed requests for information (Form
                  UCC-11) listing all effective Uniform Commercial Code
                  financing statements naming the Borrower as debtor and all tax
                  lien, judgment, and litigation searches for the Borrower as
                  the Lender shall deem necessary or desirable;

                           (ii)     Uniform Commercial Code financing statements
                  (Form UCC-1) duly executed by the Borrower (naming the Lender
                  as secured party and the Borrower as debtor and in form
                  acceptable for filing in all jurisdictions that the Lender
                  deems necessary or desirable to perfect the security interests
                  granted to it hereunder) and, if applicable, termination
                  statements or other releases duly filed in all jurisdictions
                  that the Lender deems necessary or desirable to perfect and
                  protect the priority of the security interests granted to it
                  hereunder in the Equipment related to such initial Loan;

                           (iii)    a Note duly executed by the Borrower
                  evidencing the amount of such Loan;


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                           (iv)     a Collateral Access Agreement duly executed
                  by the lessor or mortgagee, as the case may be, of each
                  premises where the Equipment is located;

                           (v)      certificates of insurance required under
                  Section 5.4 of this Agreement together with loss payee
                  endorsements for all such policies naming the Lender as lender
                  loss payee and as an additional insured;

                           (vi)     a certificate of the Secretary or an
                  Assistant Secretary of the Borrower ("Secretary's
                  Certificate") certifying (A) that attached to the Secretary's
                  Certificate is a true, complete, and accurate copy of the
                  resolutions of the Board of Directors of the Borrower (or a
                  unanimous consent of directors in lieu thereof) authorizing
                  the execution, delivery, and performance of this Agreement,
                  the other Loan Documents, and the transactions contemplated
                  hereby and thereby, and that such resolutions have not been
                  amended or modified since the date of such certification and
                  are in full force and effect; (B) the incumbency, names, and
                  true signatures of the officers of the Borrower authorized to
                  sign the Loan Documents to which it is a party; (C) that
                  attached to the Secretary's Certificate is a true and correct
                  copy of the Articles or Certificate of Incorporation of the
                  Company, as amended, which Articles or Certificate of
                  Incorporation have not been further modified, repealed or
                  rescinded and are in full force and effect; (D) that attached
                  to the Secretary's Certificate of the Borrower is a true and
                  correct copy of the Bylaws, as amended, which Bylaws of the
                  Company have not been further modified, repealed or rescinded
                  and are in full force and effect; and (E) that attached to the
                  Secretary's Certificate is a valid Certificate of Good
                  Standing issued by the Secretary of the State of the
                  Borrower's state of incorporation;

                           (vii)    the opinion of counsel for the Borrower
                  covering such matters incident to the transactions
                  contemplated by this Agreement as the Lender may reasonably
                  require; and

                           (viii)   such other agreements and instruments as the
                  Lender may reasonably request.

                  (b)      There shall be no pending or, to the knowledge of the
Borrower after reasonable inquiry, threatened litigation, proceeding, inquiry,
or other action (i) seeking an injunction or other restraining order, damages,
or other relief with respect to the transactions contemplated by this Agreement
or the other Loan Documents or thereby or (ii) which affects or could affect the
business, prospects, operations, assets, liabilities, or condition (financial or
otherwise) of the Borrower, except, in the case of clause (ii), where such
litigation, proceeding, inquiry, or other action could not be expected to have a
Material Adverse Effect in the good faith judgment of the Lender.

                  (c)      The Borrower shall have paid all fees and expenses
required to be paid by it to the Lender as of such date.

                  (d)      The security interests in the Equipment related to
the initial Loan granted in favor of the Lender under this Agreement shall have
been duly perfected and shall constitute first priority liens.

                           SECTION 3.4. CONDITIONS PRECEDENT TO EACH LOAN. The
obligation of the Lender to make each Loan is subject to the satisfaction of the
following conditions precedent:

                  (a)      the Lender shall have received the documents,
agreements, and instruments set forth in Section 3.3(a)(i) through (v)
applicable to such Loan, each in form and substance satisfactory to the Lender
and its counsel and each dated the date of such Loan or as of an earlier date
acceptable to the Lender;

                  (b)      the Lender shall have received a Schedule of the
Equipment related to such Loan, in form and substance satisfactory to the Lender
and its counsel, and the security interests in such Equipment related to such
Loan granted in favor of the Lender under this Agreement shall have been duly
perfected and shall constitute first priority liens;


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                  (c)      all representations and warranties contained in this
Agreement and the other Loan Documents shall be true and correct in all material
respects on and as of the date of such Loan as if then made, other than
representations and warranties that expressly relate solely to an earlier date,
in which case they shall have been true and correct in all material respects as
of such earlier date;

                  (d)      no Event of Default or event which with the giving of
notice or the passage of time, or both, would constitute an Event of Default
shall have occurred and be continuing or would result from the making of the
requested Loan as of the date of such request; and

                  (e)      the Borrower shall be deemed to have hereby
reaffirmed and ratified all security interests, liens, and other encumbrances
heretofore granted by the Borrower to the Lender.

                  SECTION 4. THE BORROWER'S REPRESENTATIONS AND WARRANTIES.

                           SECTION 4.1. GOOD STANDING; QUALIFIED TO DO BUSINESS.
The Borrower (a) is duly organized, validly existing, and in good standing under
the laws of the State of its organization, (b) has the power and authority to
own its properties and assets and to transact the businesses in which it is
presently, or proposes to be, engaged, and (c) is duly qualified and authorized
to do business and is in good standing in every jurisdiction in which the
failure to be so qualified could have a Material Adverse Effect on (i) the
Borrower, (ii) the Borrower's ability to perform its obligations under the Loan
Documents, or (iii) the rights of the Lender hereunder.

                           SECTION 4.2. DUE EXECUTION, ETC. The execution,
delivery, and performance by the Borrower of each of the Loan Documents to which
it is a party are within the powers of the Borrower, do not contravene the
organizational documents, if any, of the Borrower, and do not (a) violate any
law or regulation, or any order or decree of any court or governmental
authority, (b) conflict with or result in a breach of, or constitute a default
under, any indenture, mortgage, or deed of trust or any lease, agreement, or
other instrument binding on the Borrower or any of its properties, except as
would have a Material Adverse Effect upon the Borrower, or (c) require the
consent, authorization by, or approval of or notice to or filing or registration
with any governmental authority or other Person. This Agreement is, and each of
the other Loan Documents to which the Borrower is or will be a party, when
delivered hereunder or thereunder, will be, the legal, valid, and binding
obligation of the Borrower enforceable against the Borrower in accordance with
their respective terms, except as enforceability may be limited by bankruptcy,
insolvency, or similar laws affecting creditors' rights generally and by general
principles of equity.

                           SECTION 4.3. SOLVENCY; NO LIENS. The Borrower is
Solvent and will be Solvent upon the completion of all transactions contemplated
to occur hereunder (including, without limitation, the Loan to be made on the
Effective Date); the security interests granted herein constitute and shall at
all times constitute the first and only liens on the Collateral other than
Permitted Liens; and the Borrower is, or will be at the time additional
Collateral is acquired by it, the absolute owner of the Collateral with full
right to pledge, sell, consign, transfer, and create a security interest
therein, free and clear of any and all claims or liens in favor of any other
Person other than Permitted Liens.

                           SECTION 4.4. NO JUDGMENTS, LITIGATION. No judgments
are outstanding against the Borrower nor is there now pending or, to the best of
the Borrower's knowledge after reasonable inquiry, threatened any litigation,
contested claim, or governmental proceeding by or against the Borrower except
judgments and pending or threatened litigation, contested claims, and
governmental proceedings which would not, in the aggregate, have a Material
Adverse Effect on the Borrower.

                           SECTION 4.5. NO DEFAULTS. The Borrower is not in
default or has not received a notice of default under any material contract,
lease, or commitment to which it is a party or by which it is bound. The
Borrower knows of no dispute regarding any contract, lease, or commitment which
could have a Material Adverse Effect on the Borrower.

                           SECTION 4.6. COLLATERAL LOCATIONS. On the date
hereof, each item of the Collateral is located at the place of business
specified in the applicable Schedule.


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                           SECTION 4.7. NO EVENTS OF DEFAULT. No Event of
Default has occurred and is continuing nor has any event occurred which, with
the giving of notice or the passage of time, or both, would constitute an Event
of Default.

                           SECTION 4.8. NO LIMITATION ON LENDER'S RIGHTS. Except
as permitted herein, none of the Collateral is subject to contractual
obligations that may restrict or inhibit the Lender's rights or abilities to
sell or dispose of the Collateral or any part thereof after the occurrence of an
Event of Default.

                           SECTION 4.9.PERFECTION AND PRIORITY OF SECURITY
INTEREST. This Agreement creates a valid and, upon completion of all required
filings of financing statements, perfected first priority and exclusive security
interest in the Collateral, securing the payment of all the Obligations.

                           SECTION 4.10. MODEL AND SERIAL NUMBERS. The Schedules
set forth the true and correct model number and serial number of each item of
Equipment that constitutes Collateral.

                           SECTION 4.11. ACCURACY AND COMPLETENESS OF
INFORMATION. All data, reports, and information heretofore, contemporaneously,
or hereafter furnished by or on behalf of the Borrower in writing to the Lender
or for purposes of or in connection with this Agreement or any other Loan
Document, or any transaction contemplated hereby or thereby, are or will be true
and accurate in all material respects on the date as of which such data,
reports, and information are dated or certified and not incomplete by omitting
to state any material fact necessary to make such data, reports, and information
not misleading at such time (considered in the full context of all other
information provided to Lender). There are no facts now known to the Borrower
which individually or in the aggregate would reasonably be expected to have a
Material Adverse Effect and which have not been specified herein, in the
Financial Statements, or in any certificate, opinion, or other written statement
previously furnished by the Borrower to the Lender.

                           SECTION 4.12. PRICE OF EQUIPMENT. The cost of each
item of Equipment does not exceed the fair and usual price for such type of
equipment purchased in like quantity and reflects all discounts, rebates and
allowances for the Equipment (including, without limitation, discounts for
advertising, prompt payment, testing, or other services) given to the Borrower
by the manufacturer, supplier, or any other person.

                  SECTION 5. COVENANTS OF THE BORROWER.

                           SECTION 5.1. EXISTENCE, ETC. The Borrower shall: (a)
retain its existence and its current yearly accounting cycle, (b) maintain in
full force and effect all licenses, bonds, franchises, leases, trademarks,
patents, contracts, and other rights necessary or desirable to the profitable
conduct of its business unless the failure to do so could not reasonably be
expected to have a Material Adverse Effect on the Borrower, (c) continue in, and
limit its operations to, the same general lines of business as those presently
conducted by it, and (d) comply with all applicable laws and regulations of any
federal, state, or local governmental authority, except for such laws and
regulations the violations of which would not, in the aggregate, have a Material
Adverse Effect on the Borrower.

                           SECTION 5.2. NOTICE TO THE LENDER. As soon as
possible, and in any event within five days after the Borrower obtains knowledge
of the following, the Borrower will give written notice to the Lender of (a) any
proceeding instituted or threatened to be instituted by or against the Borrower
in any federal, state, local, or foreign court or before any commission or other
regulatory body (federal, state, local, or foreign) involving a sum, together
with the sum involved in all other similar proceedings, which would reasonably
be expected to have a Material Adverse Effect on the Borrower, (b) any contract
that is terminated or amended and which has had or could reasonably be expected
to have a Material Adverse Effect on the Borrower, (c) the occurrence of any
Material Adverse Change with respect to the Borrower, and (d) the occurrence of
any Event of Default or event or condition which, with notice or lapse of time
or both, would constitute an Event of Default, together with a statement of the
action which the Borrower has taken or proposes to take with respect thereto.


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                           SECTION 5.3. MAINTENANCE OF BOOKS AND RECORDS. The
Borrower will maintain books and records pertaining to the Collateral in such
detail, form, and scope as the Lender shall require in its commercially
reasonable judgment. The Borrower agrees that the Lender or its agents may enter
upon the Borrower's premises at any time and from time to time during normal
business hours, and at any time upon the occurrence and continuance of an Event
of Default, for the purpose of inspecting the Collateral and any and all records
pertaining thereto.

                           SECTION 5.4. INSURANCE. The Borrower will maintain
insurance on the Collateral under such policies of insurance, with such
insurance companies, in such amounts, and covering such risks as are at all
times satisfactory to the Lender. All such policies shall be made payable to the
Lender, in case of loss, under a standard non-contributory "lender" or "secured
party" clause and are to contain such other provisions as the Lender may
reasonably require to protect the Lender's interests in the Collateral and to
any payments to be made under such policies. Certificates of insurance policies
are to be delivered to the Lender, premium prepaid, with the loss payable
endorsement in the Lender's favor, and shall provide for not less than thirty
days' prior written notice to the Lender, of any alteration or cancellation of
coverage. If the Borrower fails to maintain such insurance, the Lender may
arrange for (at the Borrower's expense and without any responsibility on the
Lender's part for) obtaining the insurance. Unless the Lender shall otherwise
agree with the Borrower in writing, the Lender shall have the sole right, in the
name of the Lender or the Borrower, to file claims under any insurance policies,
to receive and give acquittance for any payments that may be payable thereunder,
and to execute any endorsements, receipts, releases, assignments, reassignments,
or other documents that may be necessary to effect the collection, compromise,
or settlement of any claims under any such insurance policies.

                           SECTION 5.5. TAXES. The Borrower will pay, when due,
all taxes, assessments, claims, and other governmental charges ("Taxes")
lawfully levied or assessed against the Borrower or the Collateral other than
Taxes that are being currently contested in good faith by the Borrower by
appropriate proceedings instituted and for which an adequate reserve is being
maintained by the Borrower in accordance with GAAP. If any Taxes remain unpaid
after the date fixed for the payment thereof, or if any lien shall be claimed
therefor, then, with notice to the Borrower, but on the Borrower's behalf, the
Lender may pay such Taxes, and the amount thereof shall be included in the
Obligations.

                           SECTION 5.6. BORROWER TO DEFEND COLLATERAL AGAINST
CLAIMS; FEES ON COLLATERAL. The Borrower will defend the Collateral against all
claims and demands of all Persons at any time claiming the same or any interest
therein. The Borrower will not permit any notice creating or otherwise relating
to liens on the Collateral or any portion thereof to exist or be on file in any
public office other than Permitted Liens. The Borrower shall promptly pay, when
payable, all transportation, storage, and warehousing charges and license fees,
registration fees, assessments, charges, permit fees, and taxes (municipal,
state, and federal) which may now or hereafter be imposed upon the ownership,
leasing, renting, possession, sale, or use of the Collateral, other than taxes
on or measured by the Lender's income and fees, assessments, charges, and Taxes
which are being contested in good faith by appropriate proceedings diligently
conducted and with respect to which adequate reserves are maintained to the
extent required by GAAP.

                           SECTION 5.7. NO CHANGE OF LOCATION, STRUCTURE, OR
IDENTITY. The Borrower will not (a) change the location of its chief executive
office or establish any place of business other than those specified herein or
(b) move or permit the movement of any item of Collateral from the location
specified in the applicable Schedule, except that the Borrower may change its
chief executive office and keep Collateral at other locations within the United
States provided that the Borrower has delivered to the Lender (i) prior written
notice thereof and (ii) duly executed financing statements and other agreements
and instruments (all in form and substance satisfactory to the Lender) necessary
or, in the opinion of the Lender, desirable to perfect and maintain in favor of
the Lender a first priority security interest in the Collateral. Notwithstanding
anything to the contrary in the immediately preceding sentence, the Borrower may
keep any Collateral consisting of motor vehicles or rolling stock at any
location in the United States provided that the Lender's security interest in
any such Collateral is conspicuously marked on the certificate of title thereof
and the Borrower has complied with the provisions of Section 5.9.


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                           SECTION 5.8. USE OF COLLATERAL; LICENSES; REPAIR. The
Collateral shall be operated by competent, qualified personnel in connection
with the Borrower's business purposes, for the purpose for which the Collateral
was designed and in accordance with applicable operating instructions, laws, and
government regulations, and the Borrower shall use every reasonable precaution
to prevent loss or damage to the Collateral from fire and other hazards. The
Collateral shall not be used or operated for personal, family, or household
purposes. The Borrower shall procure and maintain in effect all orders,
licenses, certificates, permits, approvals, and consents required by federal,
state, or local laws or by any governmental body, agency, or authority in
connection with the delivery, installation, use, and operation of the
Collateral. The Borrower shall keep all of the Equipment in a satisfactory state
of repair and satisfactory operating condition in accordance with industry
standards, and will make all repairs and replacements when and where necessary
and practical. The Borrower will not waste or destroy the Equipment or any part
thereof, and will not be negligent in the care or use thereof. The Equipment
shall not be annexed or affixed to or become part of any realty without the
Lender's prior written consent.

                           SECTION 5.9. FURTHER ASSURANCES. The Borrower will,
promptly upon request by the Lender, execute and deliver or use its best efforts
to obtain any document reasonably required by the Lender (including, without
limitation, warehouseman or processor disclaimers, mortgagee waivers, landlord
disclaimers, or subordination agreements with respect to the Obligations and the
Collateral), give any notices, execute and file any financing statements,
mortgages, or other documents (all in form and substance satisfactory to the
Lender), mark any chattel paper, deliver any chattel paper or instruments to the
Lender, and take any other actions that are reasonably necessary or, in the
opinion of the Lender, desirable to perfect or continue the perfection and the
first priority of the Lender's security interest in the Collateral, to protect
the Collateral against the rights, claims, or interests of any Persons, or to
effect the purposes of this Agreement. The Borrower hereby authorizes the Lender
to file one or more financing or continuation statements, and amendments
thereto, relating to all or any part of the Collateral without the signature of
the Borrower where permitted by law. A carbon, photographic, or other
reproduction of this Agreement or any financing statement covering the
Collateral or any part thereof shall be sufficient as a financing statement
where permitted by law. To the extent required under this Agreement, the
Borrower will pay all costs incurred in connection with any of the foregoing.

                           SECTION 5.10. NO DISPOSITION OF COLLATERAL. The
Borrower will not in any way hypothecate or create or permit to exist any lien,
security interest, charge, or encumbrance on or other interest in any of the
Collateral, except for the lien and security interest granted hereby and
Permitted Liens which are junior to the lien and security interest of the
Lender, and the Borrower will not sell, transfer, assign, pledge, collaterally
assign, exchange, or otherwise dispose of any of the Collateral. In the event
the Collateral, or any part thereof, is sold, transferred, assigned, exchanged,
or otherwise disposed of in violation of these provisions, the security interest
of the Lender shall continue in such Collateral or part thereof notwithstanding
such sale, transfer, assignment, exchange, or other disposition, and the
Borrower will hold the proceeds thereof in a separate account for the benefit of
the Lender. Following such a sale, the Borrower will transfer such proceeds to
the Lender in kind.

                           SECTION 5.11. NO LIMITATION ON LENDER'S RIGHTS. The
Borrower will not enter into any contractual obligations which may restrict or
inhibit the Lender's rights or ability to sell or otherwise dispose of the
Collateral or any part thereof.

                           SECTION 5.12. PROTECTION OF COLLATERAL. Upon notice
to the Borrower (provided that if an Event of Default has occurred and is
continuing the Lender need not give any notice), the Lender shall have the right
at any time to make any payments and do any other acts the Lender may deem
necessary to protect its security interests in the Collateral, including,
without limitation, the rights to satisfy, purchase, contest, or compromise any
encumbrance, charge, or lien which, in the reasonable judgment of the Lender,
appears to be prior to or superior to the security interests granted hereunder,
and appear in, and defend any action or proceeding purporting to affect its
security interests in, or the value of, any of the Collateral. The Borrower
hereby agrees to reimburse the Lender for all payments made and expenses
incurred under this Agreement including reasonable fees, expenses, and
disbursements of attorneys and paralegals (including the allocated costs of
in-house counsel) acting for the Lender, including any of the foregoing payments
under, or acts taken to protect its security interests in, any of the
Collateral, which amounts shall be secured under this Agreement, and agrees it
shall be bound by any payment made or act taken by the Lender hereunder absent
the Lender's gross negligence or willful misconduct. The Lender shall have no
obligation to make any of the foregoing payments or perform any of the foregoing
acts.


                                        8
<PAGE>


                           SECTION 5.13. DELIVERY OF ITEMS. The Borrower will
(a) promptly (but in no event later than three Business Days) after its receipt
thereof, deliver to the Lender any documents or certificates of title issued
with respect to any property included in the Collateral, and any promissory
notes, letters of credit or instruments related to or otherwise in connection
with any property included in the Collateral, which in any such case come into
the possession of the Borrower, or shall cause the issuer thereof to deliver any
of the same directly to the Lender, in each case with any necessary endorsements
in favor of the Lender and (b) deliver to the Lender as soon as available copies
of any and all press releases and other similar communications issued by the
Borrower.

                           SECTION 5.14. SOLVENCY. The Borrower shall be and
remain Solvent at all times.

                           SECTION 5.15. FUNDAMENTAL CHANGES. The Borrower shall
not (a) amend or modify its name, unless the Borrower delivers to the Lender
thirty days prior to any such proposed amendment or modification written notice
of such amendment or modification and within ten days before such amendment or
modification delivers executed Uniform Commercial Code financing statements (in
form and substance satisfactory to the Lender) or (b) merge or consolidate with
any other entity or make any material change in its capital structure, in each
case without the Lender's prior written consent which shall not be unreasonably
withheld.

                           SECTION 5.16. ADDITIONAL REQUIREMENTS. The Borrower
shall take all such further actions and execute all such further documents and
instruments as the Lender may reasonably request.

                  SECTION 6. FINANCIAL STATEMENTS. Until the payment and
satisfaction in full of all Obligations, the Borrower shall deliver to the
Lender the following financial information:

                           SECTION 6.1. ANNUAL FINANCIAL STATEMENTS. As soon as
available, but not later than 120 days after the end of each fiscal year of the
Borrower and its consolidated subsidiaries, the consolidated balance sheet,
income statement, and statements of cash flows and shareholders equity for the
Borrower and its consolidated subsidiaries (the "Financial Statements") for such
year, reported on by independent certified public accountants without an adverse
qualification; and

                           SECTION 6.2. QUARTERLY FINANCIAL STATEMENTS. As soon
as available, but not later than 60 days after the end of each of the first
three fiscal quarters in any fiscal year of the Borrower and its consolidated
subsidiaries, the Financial Statements for such fiscal quarter, together with a
certification duly executed by a responsible officer of the Borrower that such
Financial Statements have been prepared in accordance with GAAP and are fairly
stated in all material respects (subject to normal year-end audit adjustments).

                  SECTION 7. EVENTS OF DEFAULT. The occurrence of any of the
following events shall constitute an Event of Default hereunder:

                           (a)      the Borrower shall fail to pay within five
days of when due any amount required to be paid by the Borrower under or in
connection with any Note and this Agreement;

                           (b)      any representation or warranty made or
deemed made by the Borrower under or in connection with any Loan Document or any
Financial Statement shall prove to have been false or incorrect in any material
respect when made;

                           (c)      the Borrower shall fail to perform or
observe (i) any of the terms, covenants or agreements contained in Sections 5.4,
5.7, 5.10, 5.14, or 5.15 hereof or (ii) any other term, covenant, or agreement
contained in any Loan Document (other than the other Events of Default specified
in this Section 7) and such failure remains unremedied for the earlier of
fifteen days from (A) the date on which the Lender has given the Borrower
written notice of such failure and (B) the date on which the Borrower knew or
should reasonably have known of such failure;

                           (d)      any provision of any Loan Document to which
the Borrower is a party shall for


                                        9
<PAGE>


any reason cease to be valid and binding on the Borrower, or the Borrower
shall so state;

                           (e)      dissolution, liquidation, winding up, or
cessation of the Borrower's business, failure of the Borrower generally to pay
its debts as they mature, admission in writing by the Borrower of its inability
generally to pay its debts as they mature, or calling of a meeting of the
Borrower's creditors for purposes of compromising any of the Borrower's debts;

                           (f)      the commencement by or against the Borrower
of any bankruptcy, insolvency, arrangement, reorganization, receivership, or
similar proceedings under any federal or state law and, in the case of any such
involuntary proceeding, such proceeding remains undismissed or unstayed for
forty-five days following the commencement thereof, or any action by the
Borrower is taken authorizing any such proceedings;

                           (g)      an assignment for the benefit of creditors
is made by the Borrower, whether voluntary or involuntary, the appointment of a
trustee, custodian, receiver, or similar official for the Borrower or for any
substantial property of the Borrower, or any action by the Borrower authorizing
any such proceeding;

                           (h)      the Borrower shall default in (i) the
payment of principal or interest on any indebtedness in excess of $50,000 (other
than the Obligations) beyond the period of grace, if any, provided in the
instrument or agreement under which such indebtedness was created; or (ii) the
observance or performance of any other agreement or condition relating to any
such indebtedness or contained in any instrument or agreement relating thereto,
or any other event shall occur or condition exist, the effect of which default
or other event or condition is to cause, or to permit the holder or holders of
such indebtedness to cause, with the giving of notice if required, such
indebtedness to become due prior to its stated maturity and such default shall
not be remedied, cured, waived or consented to within the period of grace
thereto;

                           (i)      the Borrower suffers or sustains a Material
Adverse Change;

                           (j)      any tax lien, other than a Permitted Lien,
is filed of record against the Borrower and is not bonded or discharged within
five Business Days;

                           (k)      any final judgment which has had or could
reasonably be expected to have a Material Adverse Effect on the Borrower and
such judgment shall not be stayed, vacated, bonded, or discharged within sixty
days;

                           (l)      any material covenant, agreement, or
obligation, as determined in the sole discretion of the Lender, made by the
Borrower and contained in or evidenced by any of the Loan Documents shall cease
to be enforceable, or shall be determined to be unenforceable, in accordance
with its terms; the Borrower shall deny or disaffirm the Obligations under any
of the Loan Documents or any liens granted in connection therewith; or any liens
granted on any of the Collateral in favor of the Lender shall be determined to
be void, voidable, or invalid, or shall not be given the priority contemplated
by this Agreement; or

                           (m)      there is a change in more than 35% of the
ownership of any equity interests of the Borrower on the date hereof or more
than 35% of such interests become subject to any contractual, judicial, or
statutory lien, charge, security interest, or encumbrance.

                  SECTION 8. REMEDIES. If any Event of Default shall have
occurred and be continuing:

                           (a)      The Lender may, without prejudice to any of
its other rights under any Loan Document or Applicable Law, declare all
Obligations to be immediately due and payable (except with respect to any Event
of Default set forth in Section 7(f) hereof, in which case all Obligations shall
automatically become immediately due and payable without necessity of any
declaration) without presentment, representation, demand of payment, or protest,
which are hereby expressly waived.

                           (b)      The Lender may take possession of the
Collateral and, for that purpose may


                                        10
<PAGE>


enter, with the aid and assistance of any person or persons, any premises
where the Collateral or any part hereof is, or may be placed, and remove the
same.

                           (c)      The obligation of the Lender, if any, to
make additional Loans or financial accommodations of any kind to the Borrower
shall immediately terminate.

                           (d)      The Lender may exercise in respect of the
Collateral, in addition to other rights and remedies provided for herein (or in
any Loan Document) or otherwise available to it, all the rights and remedies of
a secured party under the applicable Uniform Commercial Code (the "Code")
whether or not the Code applies to the affected Collateral and also may (i)
require the Borrower to, and the Borrower hereby agrees that it will at its
expense and upon request of the Lender forthwith, assemble all or part of the
Collateral as directed by the Lender and make it available to the Lender at a
place to be designated by the Lender that is reasonably convenient to both
parties and (ii) without notice except as specified below, sell the Collateral
or any part thereof in one or more parcels at public or private sale, at any of
the Lender's offices or elsewhere, for cash, on credit, or for future delivery,
and upon such other terms as the Lender may deem commercially reasonable. The
Borrower agrees that, to the extent notice of sale shall be required by law, at
least ten days' notice to the Borrower of the time and place of any public sale
or the time after which any private sale is to be made shall constitute
reasonable notification. The Lender shall not be obligated to make any sale of
Collateral regardless of notice of sale having been given. The Lender may
adjourn any public or private sale from time to time by announcement at the time
and place fixed therefor, and such sale may, without further notice, be made at
the time and place to which it was so adjourned.

                           (e)      All cash proceeds received by the Lender in
respect of any sale of, collection from, or other realization upon all or any
part of the Collateral may, in the discretion of the Lender, be held by the
Lender as collateral for, or then or at any time thereafter applied in whole or
in part by the Lender against, all or any part of the Obligations in such order
as the Lender shall elect. Any surplus of such cash or cash proceeds held by the
Lender and remaining after the full and final payment of all the Obligations
shall be paid over to the Borrower or to such other Person to which the Lender
may be required under applicable law, or directed by a court of competent
jurisdiction, to make payment of such surplus.

                  SECTION 9. MISCELLANEOUS PROVISIONS.

                           SECTION 9.1. NOTICES. Except as otherwise provided
herein, all notices, approvals, consents, correspondence, or other
communications required or desired to be given hereunder shall be given in
writing and shall be delivered by overnight courier, hand delivery, or certified
or registered mail, postage prepaid, if to the Lender, then to Transamerica
Technology Finance Division, 76 Batterson Park Road, Farmington, Connecticut
06032, Attention: Legal Department, with a copy to the Lender at Riverway II,
West Office Tower, 9399 West Higgins Road, Rosemont, Illinois 60018, Attention:
Legal Department, and if to the Borrower, then to 5935 Darwin Court, Carlsbad,
California 92008, or such other address as shall be designated by the Borrower
or the Lender to the other party in accordance herewith. All such notices and
correspondence shall be effective when received.

                           SECTION 9.2. HEADINGS. The headings in this Agreement
are for purposes of reference only and shall not affect the meaning or
construction of any provision of this Agreement.

                           SECTION 9.3. ASSIGNMENTS. The Borrower shall not have
the right to assign any Note or this Agreement or any interest therein unless
the Lender shall have given the Borrower prior written consent and the Borrower
and its assignee shall have delivered assignment documentation in form and
substance satisfactory to the Lender in its sole discretion. The Lender may
assign its rights and delegate its obligations under any Note or this Agreement.

                           SECTION 9.4. AMENDMENTS, WAIVERS, AND CONSENTS. Any
amendment or waiver of any provision of this Agreement and any consent to any
departure by the Borrower from any provision of this Agreement shall be
effective only by a writing signed by the Lender and shall bind and benefit the
Borrower and the Lender and their respective successors and assigns, subject, in
the case of the Borrower, to the first sentence of Section 9.3.


                                        11
<PAGE>


                           SECTION 9.5. INTERPRETATION OF AGREEMENT. Time is of
the essence in each provision of this Agreement of which time is an element. All
terms not defined herein or in a Note shall have the meaning set forth in the
applicable Code, except where the context otherwise requires. To the extent a
term or provision of this Agreement conflicts with any Note, or any term or
provision thereof, and is not dealt with herein with more specificity, this
Agreement shall control with respect to the subject matter of such term or
provision. Acceptance of or acquiescence in a course of performance rendered
under this Agreement shall not be relevant in determining the meaning of this
Agreement even though the accepting or acquiescing party had knowledge of the
nature of the performance and opportunity for objection.

                           SECTION 9.6. CONTINUING SECURITY INTEREST. This
Agreement shall create a continuing security interest in the Collateral and
shall (i) remain in full force and effect until the indefeasible payment in full
of the Obligations, (ii) be binding upon the Borrower and its successors and
assigns and (iii) inure, together with the rights and remedies of the Lender
hereunder, to the benefit of the Lender and its successors, transferees, and
assigns.

                           SECTION 9.7. REINSTATEMENT. To the extent permitted
by law, this Agreement and the rights and powers granted to the Lender hereunder
and under the Loan Documents shall continue to be effective or be reinstated if
at any time any amount received by the Lender in respect of the Obligations is
rescinded or must otherwise be restored or returned by the Lender upon the
insolvency, bankruptcy, dissolution, liquidation, or reorganization of the
Borrower or upon the appointment of any receiver, intervenor, conservator,
trustee, or similar official for the Borrower or any substantial part of its
assets, or otherwise, all as though such payments had not been made.

                           SECTION 9.8. SURVIVAL OF PROVISIONS. All
representations, warranties, and covenants of the Borrower contained herein
shall survive the execution and delivery of this Agreement, and shall terminate
only upon the full and final payment and performance by the Borrower of the
Obligations secured hereby.

                           SECTION 9.9. INDEMNIFICATION. The Borrower agrees to
indemnify and hold harmless the Lender and its directors, officers, agents,
employees, and counsel from and against any and all costs, expenses, claims, or
liability incurred by the Lender or such Person hereunder and under any other
Loan Document or in connection herewith or therewith, unless such claim or
liability shall be due to willful misconduct or gross negligence on the part of
the Lender or such Person.

                           SECTION 9.10. COUNTERPARTS; TELECOPIED SIGNATURES.
This Agreement may be executed in counterparts, each of which when so executed
and delivered shall be an original, but both of which shall together constitute
one and the same instrument. This Agreement and each of the other Loan Documents
and any notices given in connection herewith or therewith may be executed and
delivered by telecopier or other facsimile transmission all with the same force
and effect as if the same was a fully executed and delivered original manual
counterpart.

                           SECTION 9.11. SEVERABILITY. In case any provision in
or obligation under this Agreement or any Note or any other Loan Document shall
be invalid, illegal, or unenforceable in any jurisdiction, the validity,
legality, and enforceability of the remaining provisions or obligations, or of
such provision or obligation in any other jurisdiction, shall not in any way be
affected or impaired thereby.

                           SECTION 9.12. DELAYS; PARTIAL EXERCISE OF REMEDIES.
No delay of the Lender to exercise any right or remedy hereunder, whether before
or after the happening of any Event of Default, shall impair any such right or
shall operate as a waiver thereof or as a waiver of any such Event of Default.
No single or partial exercise by the Lender of any right or remedy shall
preclude any other or further exercise thereof, or preclude any other right or
remedy.

                           SECTION 9.13. ENTIRE AGREEMENT. The Borrower and the
Lender agree that this Agreement, the Schedule hereto, and the Commitment Letter
are the complete and exclusive statement and



                                        12
<PAGE>


agreement between the parties with respect to the subject matter hereof,
superseding all proposals and prior agreements, oral or written, and all
other communications between the parties with respect to the subject matter
hereof. Should there exist any inconsistency between the terms of the
Commitment Letter and this Agreement, the terms of this Agreement shall
prevail.

                           SECTION 9.14. SETOFF. In addition to and not in
limitation of all rights of offset that the Lender may have under Applicable
Law, and whether or not the Lender has made any demand or the Obligations of the
Borrower have matured, the Lender shall have the right to appropriate and apply
to the payment of the Obligations of the Borrower all deposits and other
obligations then or thereafter owing by the Lender to or for the credit or the
account of the Borrower.

                           SECTION 9.15. WAIVER OF JURY TRIAL. THE BORROWER AND
THE LENDER IRREVOCABLY WAIVE ALL RIGHT TO TRIAL BY JURY IN ANY ACTION,
PROCEEDING, OR COUNTERCLAIM ARISING OUT OF OR RELATING TO THIS AGREEMENT, ANY
OTHER LOAN DOCUMENT, OR THE TRANSACTIONS CONTEMPLATED HEREBY OR THEREBY.

                           SECTION 9.16. GOVERNING LAW. THE VALIDITY,
INTERPRETATION, AND ENFORCEMENT OF THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF ILLINOIS WITHOUT GIVING
EFFECT TO THE CONFLICT OF LAW PRINCIPLES THEREOF.

                           SECTION 9.17. VENUE; SERVICE OF PROCESS. ANY LEGAL
ACTION OR PROCEEDING WITH RESPECT TO THIS AGREEMENT OR ANY OTHER LOAN DOCUMENT
MAY BE BROUGHT IN THE COURTS OF THE STATE OF ILLINOIS SITUATED IN COOK COUNTY,
OR OF THE UNITED STATES OF AMERICA FOR THE NORTHERN DISTRICT OF ILLINOIS, AND,
BY EXECUTION AND DELIVERY OF THIS AGREEMENT, THE BORROWER HEREBY ACCEPTS FOR
ITSELF AND IN RESPECT OF ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, THE
JURISDICTION OF THE AFORESAID COURTS. THE BORROWER HEREBY IRREVOCABLY WAIVES, IN
CONNECTION WITH ANY SUCH ACTION OR PROCEEDING, (a) ANY OBJECTION, INCLUDING,
WITHOUT LIMITATION, ANY OBJECTION TO THE LAYING OF VENUE OR BASED ON THE GROUNDS
OF FORUM NON CONVENIENS, THAT IT MAY NOW OR HEREAFTER HAVE TO THE BRINGING OF
ANY SUCH ACTION OR PROCEEDING IN SUCH RESPECTIVE JURISDICTIONS AND (b) THE RIGHT
TO INTERPOSE ANY NONCOMPULSORY SETOFF, COUNTERCLAIM, OR CROSS-CLAIM. THE
BORROWER IRREVOCABLY CONSENTS TO THE SERVICE OF PROCESS OF ANY OF THE
AFOREMENTIONED COURTS IN ANY SUCH ACTION OR PROCEEDING BY THE MAILING OF COPIES
THEREOF BY REGISTERED OR CERTIFIED MAIL, POSTAGE PREPAID, TO THE BORROWER AT THE
ADDRESS FOR IT SPECIFIED IN SECTION 9.1 HEREOF. NOTHING HEREIN SHALL AFFECT THE
RIGHT OF THE LENDER TO SERVE PROCESS IN ANY OTHER MANNER PERMITTED BY LAW OR TO
COMMENCE LEGAL PROCEEDINGS OR OTHERWISE PROCEED AGAINST THE BORROWER IN ANY
OTHER JURISDICTION, SUBJECT IN EACH INSTANCE TO THE PROVISIONS HEREOF WITH
RESPECT TO RIGHTS AND REMEDIES.


                                        13
<PAGE>


                           IN WITNESS WHEREOF, the undersigned Borrower has
caused this Agreement to be duly executed and delivered by its proper and duly
authorized officer as of the date first set forth above.


                                          THE IMMUNE RESPONSE CORPORATION




                                          By:   /s/ Howard Sampson
                                             ----------------------------------
                                             Name: Howard Sampson
                                             Title:   Chief Financial Officer
                                          Federal Tax ID No.: 33-0255679



                                          I.R.C. INC.




                                          By:    /s/ Howard Sampson
                                             ----------------------------------
                                             Name:  Howard Sampson
                                             Title:  Chief Financial Officer
                                          Federal Tax ID No.: 33-0324090



Accepted as of the
    30th day of September, 1999
   -----

TRANSAMERICA BUSINESS CREDIT CORPORATION




By:    /s/ Gary P. Moro
----------------------------------------------
   Name:  Gary P. Moro
   Title: Senior Vice President


                                       14
<PAGE>


                                   SCHEDULE A

                                       TO

                           LOAN AND SECURITY AGREEMENT

Other Places of Business and Locations of Collateral (Section 4.16):

Prior Names of Obligor (Section 4.7):

Prior Trade Names of Obligor (Section 4.7):

Existing Trade Names of Obligor (Section 4.7):

Federal Tax ID (Section 4.7):







                                       15