1
                                                                EXHIBIT 3.4


                              AMENDED AND RESTATED
                                     BYLAWS
                                       OF
                                 IMMUSOL, INC.



                                   ARTICLE I.

                                    OFFICES

         Section 1. - Principal Offices.  The board of directors shall fix the
location of the principal executive office of the corporation at any place
within or outside the State of California.  If the principal executive office
is located outside this state, and the corporation has one or more business
offices in this state, the board of directors shall fix and designate a
principal business office in the State of California.

         Section 2. - Other Offices.  The board of directors may at any time
establish branch or subordinate offices at any place or places where the
corporation is qualified to do business.


                                  ARTICLE II.

                            MEETINGS OF SHAREHOLDERS

         Section 1. - Place of Meetings.  Meetings of shareholders shall be
held at any place within or outside the State of California designated by the
board of directors.  In the absence of any such designation, shareholders'
meetings shall be held at the principal executive office of the corporation.

         Section 2. - Annual Meetings of Shareholders.

         (a)     The annual meeting of shareholders shall be held each year on
a date and at a time designated by the board of directors.  At each annual
meeting directors shall be elected and any other proper business may be
transacted.

         (b)     At an annual meeting of the shareholders, only such business
shall be conducted as shall have been properly brought before the meeting.  To
be properly brought before an annual meeting, business must be:  (A) specified
in the notice of meeting (or any supplement thereto) given by or at the
direction of the board of directors, (B) otherwise properly brought before the
meeting by or at the direction of the board of directors, or (C) otherwise
properly brought before the meeting by a shareholder.  For business to be
properly brought before an annual meeting by a shareholder, the shareholder
must have
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given timely notice thereof in writing to the secretary of the corporation.  To
be timely, a shareholder's notice must be delivered to or mailed and received
at the principal executive offices of the corporation not less than one hundred
twenty (120) calendar days in advance of the date specified in the
corporation's proxy statement released to shareholders in connection with the
previous year's annual meeting of shareholders; provided, however, that in the
event that no annual meeting was held in the previous year or the date of the
annual meeting has been changed by more than thirty (30) days from the date
contemplated at the time of the previous year's proxy statement, notice by the
shareholder to be timely must be so received a reasonable time before the
solicitation is made.  A shareholder's notice to the secretary shall set forth
as to each matter the shareholder proposes to bring before the annual meeting:
(i) a brief description of the business desired to be brought before the annual
meeting and the reasons for conducting such business at the annual meeting,
(ii) the name and address, as they appear on the corporation's books, of the
shareholder proposing such business, (iii) the class and number of shares of
the corporation which are beneficially owned by the shareholder, (iv) any
material interest of the shareholder in such business and (v) any other
information that is required to be provided by the shareholder pursuant to
Regulation 14A under the Securities Exchange Act of 1934, as amended (the "1934
Act"), in his capacity as a proponent to a shareholder proposal.
Notwithstanding the foregoing, in order to include information with respect to
a shareholder proposal in the proxy statement and form of proxy for a
shareholders' meeting, shareholders must provide notice as required by the
regulations promulgated under the 1934 Act.  Notwithstanding anything in these
Bylaws to the contrary, no business shall be conducted at any annual meeting
except in accordance with the procedures set forth in this paragraph (b).  The
chairman of the annual meeting shall, if the facts warrant, determine and
declare at the meeting that business was not properly brought before the
meeting and in accordance with the provisions of this paragraph (b), and, if he
should so determine, he shall so declare at the meeting that any such business
not properly brought before the meeting shall not be transacted.

         (c)     Only persons who are nominated in accordance with the
procedures set forth in this paragraph (c) shall be eligible for election as
directors.  Nominations of persons for election to the board of directors of
the corporation may be made at a meeting of shareholders by or at the direction
of the board of directors or by any shareholder of the corporation entitled to
vote in the election of directors at the meeting who complies with the notice
procedures set forth in this paragraph (c).  Such nominations, other than those
made by or at the direction of the board of directors, shall be made pursuant
to timely notice in writing to the secretary of the corporation in accordance
with the provisions of paragraph (b) of this Section 2.  Timely notice shall
also be given of any shareholder's intention to cumulate votes in the election
of directors at a meeting if cumulative voting is available.  Such
shareholder's notice shall set forth (i) as to each person, if any, whom the
shareholder proposes to nominate for election or re-election as a director:
(A) the name, age, business address and residence address of such person, (B)
the principal occupation or employment of such person, (C) the class and number
of shares of the corporation which are beneficially owned by such person, (D) a
description of all arrangements or





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understandings between the shareholder and each nominee and any other person or
persons (naming such person or persons) pursuant to which the nominations are
to be made by the shareholder and (E) any other information relating to such
person that is required to be disclosed in solicitations of proxies for
election of directors, or is otherwise required, in each case pursuant to
Regulation 14A under the 1934 Act (including without limitation such person's
written consent to being named in the proxy statement, if any, as a nominee and
to serving as a director if elected); and (ii) as to such shareholder giving
notice, the information required to be provided pursuant to paragraph (b) of
this Section 2 and, if cumulative voting is available to such shareholder,
whether such shareholder intends to request cumulative voting in the election
of directors at the meeting.  At the request of the board of directors, any
person nominated by a shareholder for election as a director shall furnish to
the Secretary of the corporation that information required to be set forth in
the shareholder's notice of nomination which pertains to the nominee.  No
person shall be eligible for election as a director of the corporation unless
nominated in accordance with the procedures set forth in this paragraph (c).
The chairman of the meeting shall, if the facts warrant, determine and declare
at the meeting that a nomination was not made in accordance with the procedures
prescribed by these Bylaws, and if he should so determine, he shall so declare
at the meeting, and the defective nomination shall be disregarded.

         Section 3. - Special Meeting.  A special meeting of the shareholders
may be called at any time by the board of directors, or by the chairman of the
board, or by the president, or by one or more shareholders holding shares in
the aggregate entitled to cast not less than ten percent (10%) of the votes at
that meeting.

         Section 4. - Notice of Shareholders' Meetings.  All notices of
meetings of shareholders shall be sent or otherwise given in accordance with
Section 5 of this Article II not less than ten (10) nor more than sixty (60)
days before the date of the meeting.  The notice shall specify the place, date
and hour of the meeting and (a) in the case of a special meeting, the general
nature of the business to be transacted, or (b) in the case of the annual
meeting, those matters which the board of directors, at the time of giving the
notice, intends to present for action by the shareholders.  The notice of any
meeting at which directors are to be elected shall include the name of any
nominee or nominees whom, at the time of the notice, management intends to
present for election.

         If action is proposed to be taken at any meeting for approval of (A) a
contract or transaction in which a director has a direct or indirect financial
interest, pursuant to Section 310 of the Corporations Code of California, (B)
an amendment of the articles of incorporation, pursuant to Section 902 of that
Code, (C) a reorganization of the corporation, pursuant to Section 1201 of that
Code, (D) a voluntary dissolution of the corporation, pursuant to Section 1900
of that Code, or (E) a distribution in dissolution other than in accordance
with the rights of outstanding preferred shares, pursuant to Section 2007 of
that Code, the notice shall also state the general nature of that proposal.





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         Section 5. - Manner of Giving Notice; Affidavit of Notice.  Notice of
any meeting of shareholders shall be given either personally or by first-class
mail or telegraphic or other written communication, charges prepaid, addressed
to the shareholder at the address of that shareholder appearing on the books of
the corporation or given by the shareholder to the corporation for the purpose
of notice.  If no such address appears on the corporation's books or is given,
notice shall be deemed to have been given if sent to that shareholder by
first-class mail or telegraphic or other written communication to the
corporation's principal executive office, or if published at least once in a
newspaper of general circulation in the county where that office is located.
Notice shall be deemed to have been given at the time when delivered personally
or deposited in the mail or sent by telegraph or other means of written
communication.

         If any notice addressed to a shareholder at the address of that
shareholder appearing on the books of the corporation is returned to the
corporation by the United States Postal Service marked to indicate that the
United States Postal Service is unable to deliver the notice to the shareholder
at that address, all future notices or reports shall be deemed to have been
duly given without further mailing if these shall be available to the
shareholder on written demand of the shareholder at the principal executive
office of the corporation for a period of one year from the date of giving of
the notice.

         An affidavit of the mailing or other means of giving any notice of any
shareholders' meeting shall be executed by the secretary, assistant secretary
or any transfer agent of the corporation giving the notice, and shall be filed
and maintained in the minute book of the corporation.

         Section 6. - Quorum.  The presence in person or by proxy of the
holders of a majority of the shares entitled to vote at any meeting of
shareholders shall constitute a quorum for the transaction of business.  The
shareholders present at a duly called or held meeting at which a quorum is
present may continue to do business until adjournment, notwithstanding the
withdrawal of enough shareholders to leave less than a quorum, if any action
taken (other than adjournment) is approved by at least a majority of the shares
required to constitute a quorum.

         Section 7. - Adjourned Meeting; Notice.  Any shareholders' meeting,
annual or special whether or not a quorum is present, may be adjourned from
time to time by the vote of the majority of the shares represented at that
meeting, either in person or by proxy, but in the absence of a quorum, no other
business may be transacted at that meeting, except as provided in Section 6 of
this Article II.

         When any meeting of shareholders, either annual or special, is
adjourned to another time or place, notice need not be given of the adjourned
meeting if the time and place are announced at a meeting at which the
adjournment is taken, unless a new record date for the adjourned meeting is
fixed, or unless the adjournment is for more than forty-five (45) days





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from the date set for the original meeting, in which cases the board of
directors shall set a new record date.  Notice of any such adjourned meeting
shall be given to each shareholder of record entitled to vote at the adjourned
meeting in accordance with the provisions of Section 4 and 5 of this Article
II.  At any adjourned meeting the corporation may transact any business which
might have been transacted at the original meeting.

         Section 8. - Voting.  The shareholders entitled to vote at any meeting
of shareholders shall be determined in accordance with the provisions of
Section 11 of this Article II, subject to the provisions of Sections 702 to
704, inclusive, of the California General Corporation Law (relating to voting
shares held by a fiduciary, in the name of a corporation or in joint
ownership).  The shareholders' vote may be by voice vote or by ballot;
provided, however, that any election for directors must be by ballot if
demanded by any shareholder before the voting has begun.  On any matter other
than elections of directors, any shareholder may vote part of the shares in
favor of the proposal and refrain from voting the remaining shares or vote them
against the proposal, but, if the shareholder fails to specify the number of
shares which the shareholder is voting affirmatively, it will be conclusively
presumed that the shareholder's approving vote is with respect to all shares
that the shareholder is entitled to vote.  If a quorum is present, the
affirmative vote of the majority of the shares represented at the meeting and
entitled to vote on any matter (other than the election of directors) shall be
the act of the shareholders, unless the vote of a greater number or voting by
classes is required by California General Corporation Law or by the articles of
incorporation.

         Prior to the Record Date (as defined below), at a shareholders'
meeting at which directors are to be elected, no shareholder shall be entitled
to cumulate votes (i.e., cast for any one or more candidates a number of votes
greater than the number of the shareholder's shares) unless the candidates'
names have been placed in nomination prior to commencement of the voting and a
shareholder has given notice prior to commencement of the voting of the
shareholder's intention to cumulate votes.  If any shareholder has given such a
notice, then every shareholder entitled to vote may cumulate votes for
candidates in nomination and give one candidate a number of votes equal to the
number of directors to be elected multiplied by the number of votes to which
that shareholder's shares are entitled, or distribute the shareholder's votes
on the same principle among any or all of the candidates, as the shareholder
thinks fit.  The candidates receiving the highest number of votes, up to the
number of directors to be elected, shall be elected.

         The election of directors by the shareholders shall not be by
cumulative voting.  At each election of directors, each shareholder entitled to
vote may vote all the shares held by that shareholder for each of the several
nominees for director up to the number of directors to be elected.  The
shareholder may not cast more votes for any single nominee than the number of
shares held by that shareholder.  This paragraph shall become effective only
when the corporation becomes a "listed corporation" within the meaning of
Section 301.5 of the California General Corporation Law (the "Record Date").





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         Section 9. - Waiver of Notice or Consent by Absent Shareholders.  The
transactions of any meeting of shareholders, either annual or special, however
called and noticed, and wherever held, shall be as valid as though had at a
meeting duly held after regular call and notice, if a quorum be present either
in person or by proxy, and if, either before or after the meeting, each person
entitled to vote, who was not present in person or by proxy, signs a written
waiver of notice or a consent to a holding of the meeting, or an approval of
the minutes.  The waiver of notice or consent need not specify either the
business to be transacted or the purpose of any annual or special meeting of
shareholders, except that if action is taken or proposed to be taken for
approval of any of those matters specified in the second paragraph of Section 4
of this Article II, the waiver of notice or consent shall state the general
nature of the proposal.  All such waivers, consents or approvals shall be filed
with the corporate records or made a part of the minutes of the meeting.

         Attendance by a person at a meeting shall also constitute a waiver of
notice of that meeting, except when the person objects, at the beginning of the
meeting, to the transaction of any business because the meeting is not lawfully
called or convened, and except that attendance at a meeting is not a waiver of
any right to object to the consideration of matters not included in the notice
of the meeting if that objection is expressly made at the meeting.

         Section 10. - Shareholder Action By Written Consent Without a Meeting.
No action shall be taken by the shareholders of the corporation except at an
annual or special meeting of the shareholders called in accordance with these
Bylaws, and no action shall be taken by the shareholders by written consent.

         Section 11. - Record Date for Shareholder Notice and Voting.  For
purposes of determining the shareholders entitled to notice of or to vote at
any meeting, the board of directors may fix, in advance, a record date, which
shall not be more than sixty (60) days nor less than ten (10) days before the
date of any such meeting, and in this event only shareholders of record on the
date so fixed are entitled to notice and to vote, as the case may be,
notwithstanding any transfer of any shares on the books of the corporation
after the record date, except as otherwise provided in the California General
Corporation Law.

         If the board of directors does not so fix a record date, the record
date for determining shareholders entitled to notice of or to vote at a meeting
of shareholders shall be at the close of business on the business day next
preceding the day on which notice is given or, if notice is waived, at the
close of business on the business day next preceding the day on which the
meeting is held.

         Section 12. - Proxies.  Every person entitled to vote for directors or
on any other matter shall have the right to do so either in person or by one or
more agents authorized by a written proxy signed by the person and filed with
the secretary of the corporation.  A proxy shall be deemed signed if the
shareholder's name is placed on the proxy (whether by manual signature,
typewriting, telegraphic transmission or otherwise) by the shareholder or





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the shareholder's attorney-in-fact.  A validly executed proxy which does not
state that it is irrevocable shall continue in full force and effect unless (a)
revoked by the person executing it, before the vote pursuant to that proxy, by
a writing delivered to the corporation stating that the proxy is revoked, or by
a subsequent proxy executed by, or attendance at the meeting and voting in
person by, the person executing the proxy; or (b) written notice of the death
or incapacity of the maker of that proxy is received by the corporation before
the vote pursuant to that proxy is counted; provided, however, that no proxy
shall be valid after the expiration of eleven (11) months from the date of the
proxy, unless otherwise provided in the proxy.  The revocability of a proxy
that states on its face that it is irrevocable shall be governed by the
provisions of Sections 705(e) and 705(f) of the California General Corporations
Law.

         Section 13. - Inspectors of Election.  Before any meeting of
shareholders, the board of directors may appoint any persons other than
nominees for office to act as inspectors of election at the meeting or its
adjournment.  If no inspectors of election are so appointed, the chairman of
the meeting may, and on the request of any shareholder or a shareholder's proxy
shall, appoint inspectors of election at the meeting.  The number of inspectors
shall be either one (1) or three (3).  If inspectors are appointed at a meeting
on the request of one or more shareholders or proxies, the holders of a
majority of shares or their proxies present at the meeting shall determine
whether one (1) or three (3) inspectors are to be appointed.  If any person
appointed as inspector fails to appear or fails or refuses to act, the chairman
of the meeting may, and upon the request of any shareholder or a shareholder's
proxy shall, appoint a person to fill that vacancy.

         These inspectors shall:  (a)  determine the number of shares
outstanding and the voting power of each, the shares represented at the
meeting, the existence of a quorum, and the authenticity, validity, and effect
of proxies; (b) receive votes, ballots or consents; (c) hear and determine all
challenges and questions in any way arising in connection with the right to
vote; (d) count and tabulate all votes or consents; (e) determine when the
polls shall close; (f) determine the result; and (g) do any other acts that may
be proper to conduct the election or vote with fairness to all shareholders.


                                  ARTICLE III.

                                   DIRECTORS

         Section 1. - Powers.  Subject to the provisions of the California
General Corporation Law and any limitations in the articles of incorporation
and these Bylaws relating to action required to be approved by the shareholders
or by the outstanding shares, the business and affairs of the corporation shall
be managed and all corporate powers shall be exercised by or under the
direction of the board of directors.

         Section 2. - Number and Qualification of Directors.  The authorized 
number of





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directors shall not be less than five (5) nor more than nine (9) until changed
by amendment of the articles of incorporation or by a bylaw amending this
Section 2 duly adopted by the vote of holders of a majority of the outstanding
shares entitled to vote or by the Board of Directors, provided that a proposal
to reduce the authorized number or the minimum number of directors below five
(5) cannot be adopted if the votes cast against its adoption at a meeting are
equal to more than 16-2/3 percent of the outstanding shares entitled to vote.
The exact number of directors shall be fixed from time to time, within the
limits specified in the articles of incorporation or in this Section 2, by a
bylaw or amendment thereof duly adopted by the vote of a majority of the shares
entitled to vote represented at a duly held meeting at which a quorum is
present or by the board of directors.

         Subject to the foregoing provisions for changing the number of
directors, the number of directors of this corporation has been fixed at five
(5).

         Section 3. - Vacancies.  Any vacancies on the board of directors
resulting from death, resignation, disqualification, removal or other causes
shall be filled by either (i) the affirmative vote of the holders of a majority
of the outstanding shares entitled to vote; or (ii) by the affirmative vote of
a majority of the remaining directors then in office, even though less than a
quorum of the board of directors.

         Newly created directorships resulting from any increase in the number
of directors shall, unless the board of directors determines by resolution that
any such newly created directorship shall be filled by the shareholders, be
filled only by the affirmative vote of a majority of the directors then in
office, even though less than a quorum of the board of directors.  Any director
elected in accordance with the preceding sentence shall hold office until such
director's successor shall have been elected and qualified.

         A vacancy or vacancies in the board of directors shall be deemed to
exist in the event of the death, resignation or removal of any director, or if
the board of directors by resolution declares vacant the office of a director
who has been declared of unsound mind by an order of court or convicted of a
felony, or if the authorized number of directors is increased, or if the
shareholders fail, at any meeting of shareholders at which any director or
directors are elected, to elect the number of directors to be voted for at that
meeting.

         Any director may resign effective on giving written notice to the
chairman of the board, the president, the secretary or the board of directors,
unless the notice specifies a later time for that resignation to become
effective.  If the resignation of a director is effective at a future time, the
board of directors may elect a successor to take office when the resignation
becomes effective.

         No reduction of the authorized number of directors shall have the
effect of removing any director before that director's term of office expires.





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         Section 4. - Place of Meetings and Meetings by Telephone.  Regular
meetings of the board of directors may be held at any place within or outside
of the State of California that has been designated from time to time by
resolution of the board.  In the absence of such a designation, regular
meetings shall be held at the principal executive office of the corporation.
Special meetings of the board shall be held at any place within or outside the
State of California that has been designated in the notice of the meeting or,
if not stated in the notice or there is no notice, at the principal executive
office of the corporation.  Any meeting, regular or special, may be held by
conference telephone or similar communication equipment, so long as all
directors participating in the meeting can hear one another, and all such
directors shall be deemed to be present in person at the meeting.

         Section 5. - Annual Meeting.  Immediately following each annual
meeting of shareholders, the board of directors shall hold a regular meeting
for the purpose of organization, any desired election of officers and the
transaction of other business.  Notice of this meeting shall not be required.

         Section 6. - Other Regular Meetings.  Other regular meetings of the
board of directors shall be held without call at such time as shall from time
to time be fixed by the board of directors.  Such regular meetings may be held
without notice.

         Section 7. - Special Meetings.  Special meetings of the board of
directors for any purpose or purposes may be called at any time by the chairman
of the board or the president or any vice president or secretary or any two
directors.

         Notice of the time and place of special meetings shall be delivered
personally or by telephone to each director or sent by first-class mail or
telegram, charges prepaid, addressed to each director at that director's
address as it is shown on the records of the corporation.  In case the notice
is mailed, it shall be deposited in the United States mail at least four (4)
days before the time of the holding of the meeting.  In case the notice is
delivered personally or by telephone or telegram, it shall be delivered
personally or by telephone or to the telegraph company at least forty-eight
(48) hours before the time of the holding of the meeting.  Any oral notice
given personally or by telephone may be communicated either to the director or
to a person at the office of the director who the person giving the notice has
reason to believe will promptly communicate it to the director.  The notice
need not specify the purpose of the meeting nor the place if the meeting is to
be held at the principal executive office of the corporation.

         Section 8. - Quorum.  A majority of the authorized number of directors
shall constitute a quorum for the transaction of business, except to adjourn as
provided in Section 10 of this Article III.  Every act or decision done or made
by a majority of the directors present at a meeting duly held at which a quorum
is present shall be regarded as the act of the board of directors, subject to
the provisions of Section 310 of the California General Corporations Law (as to
approval of contracts or transactions in which a director has a





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direct or indirect material financial interest), Section 311 of that Code (as
to appointment of committees) and Section 317(e) of that Code (as to
indemnification of directors).  A meeting at which a quorum is initially
present may continue to transact business notwithstanding the withdrawal of
directors, if any action taken is approved by at least a majority of the
required quorum for that meeting.

         Section 9. - Waiver of Notice.  The transaction of any meeting of the
board of directors, however called and noticed or wherever held, shall be as
valid as though had at a meeting duly held after regular call and notice if a
quorum is present and if, either before or after the meeting, each of the
directors not present signs a written waiver of notice, a consent to holding
the meeting or an approval of the minutes.  The waiver of notice or consent
need not specify the purpose of the meeting.  All such waivers, consents and
approvals shall be filed with the corporate records or made a part of the
minutes of the meeting.  Notice of a meeting shall also be deemed given to any
director who attends the meeting without protesting, before or at its
commencement, the lack of notice to that director.

         Section 10. - Adjournment.  A majority of the directors present,
whether or not constituting a quorum, may adjourn any meeting to another time
and place.

         Section 11. - Notice of Adjournment.  Notice of the time and place of
holding an adjourned meeting need not be given, unless the meeting is adjourned
for more than twenty-four (24) hours, in which case notice of the time and
place shall be given before the time of the adjourned meeting, in the manner
specified in Section 7 of this Article III, to the directors who were not
present at the time of the adjournment.

         Section 12. - Action Without Meeting.  Any action required or
permitted to be taken by the board of directors may be taken without a meeting,
if all members of the board shall individually or collectively consent in
writing to that action.  Such action by written consent shall have the same
force and effect as a unanimous vote of the board of directors.  Such written
consent or consents shall be filed with the minutes of the proceedings of the
board.

         Section 13. - Fees and Compensation of Directors.  Directors and
members of committees may receive such compensation, if any, for their
services, and such reimbursement of expenses, as may be fixed or determined by
resolution of the board of directors.  This Section 13 shall not be construed
to preclude any director from serving the corporation in any other capacity as
an officer, agent, employee or otherwise, and receiving compensation for those
services.





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                                  ARTICLE IV.

                                   COMMITTEES

         Section 1. - Committees of Directors.  The board of directors may, by
resolution adopted by a majority of the authorized number of directors,
designate one or more committees, each consisting of two or more directors, to
serve at the pleasure of the board.  The board may designate one or more
directors as alternate members of any committee, who may replace any absent
member at any meeting of the committee.  Any committee, to the extent provided
in the resolution of the board, shall have all the authority of the board,
except with respect to:

         (a)     the approval of any action which, under the California General
Corporation Law, also requires shareholders' approval or approval of the
outstanding shares;

         (b)     the filling of vacancies on the board of directors or in any
committee;

         (c)     the fixing of compensation of the directors for serving on the
board or any committee;

         (d)     the amendment or repeal of bylaws or the adoption of new
bylaws;

         (e)     the amendment or repeal of any resolution of the board of
directors which by it express terms is not so amendable or repealable;

         (f)     a distribution to the shareholders of the corporation, except
at a rate or in a periodic amount or within a price range determined by the
board of directors; or

         (g)     the appointment of any other committees of the board of
directors or the members of these committees.

         Section 2. - Meetings and Action of Committees.  Meetings and action
of committees shall be governed by, and held and taken in accordance with, the
provisions of Article III of these bylaws, and specifically, Sections 4 (place
of meetings), 6 (regular meetings), 7 (special meetings and notice), 8
(quorum), 9 (waiver of notice), 10 (adjournment), 11 (notice of adjournment)
and 12 (action without meeting), with such changes in the context of those
bylaws as are necessary to substitute the committee and its members for the
board of directors and its members, except that the time of regular meetings of
committees may be determined either by resolution of the board of directors or
by resolution of the committee; special meetings of committees may also be
called by resolution of the board of directors; and notice of special meetings
of committees shall also be given to all alternate members, who shall have the
right to attend all meetings of the committee.  The board of directors may
adopt rules for the government of any committee





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not inconsistent with the provisions of these bylaws.


                                   ARTICLE V.

                                    OFFICERS

         Section 1. - Officers.  The officers of the corporation shall be a
chairman of the board or president, a secretary and a chief financial officer.
The corporation may also have, at the discretion of the board of directors, a
chairman of the board, one or more vice presidents, one or more assistant
secretaries, one or more assistant treasurers and such other officers as may be
appointed in accordance with the provisions of Section 3 of this Article V.
Any number of offices may be held by the same person.

         Section 2. - Election of Officers.  The officers of the corporation,
except such officers as may be appointed in accordance with the provisions of
Section 3 or Section 5 of this Article V, shall be chosen by the board of
directors, and each shall serve at the pleasure of the board, subject to the
rights, if any, of an officer under any contract of employment.

         Section 3. - Subordinate Officers.  The board of directors may
appoint, and may empower the president to appoint, such other officers as the
business of the corporation may require, each of whom shall hold office for
such period, have such authority and perform such duties as are provided in the
bylaws or as the board of directors may from time to time determine.

         Section 4. - Removal and Resignation of Officers.  Subject to the
rights, if any, of an officer under any contract of employment, any officer may
be removed, either with or without cause, by the board of directors, at any
regular or special meeting of the board, or, except in case of an officer
chosen by the board of directors, by an officer upon whom such power of removal
may be conferred by the board of directors.

         Any officer may resign at any time by giving written notice to the
corporation.  Any resignation shall take effect at the date of the receipt of
that notice or at any later time specified in that notice; and, unless
otherwise specified in that notice, the acceptance of the resignation shall not
be necessary to make it effective.  Any resignation is without prejudice to the
rights, if any, of the corporation under any contract to which the officer is a
party.

         Section 5. - Vacancies In Offices.  A vacancy in any office because of
death, resignation, removal, disqualification or any other cause shall be
filled in the manner prescribed in these bylaws for regular appointments to
that office.

         Section 6. - Chairman Of The Board.  The chairman of the board, if
such an officer





                                      -12-
   13
be elected, shall, if present, preside at meetings of the board of directors
and exercise and perform such other powers and duties as may be from time to
time assigned to him by the board of directors or prescribed by the bylaws.  If
there is no president, the chairman of the board shall in addition be the chief
executive officer of the corporation and shall have the powers and duties
prescribed in Section 7 of this Article V.

         Section 7. - President.  Subject to such supervisory powers, if any,
as may be given by the board of directors to the chairman of the board, if
there be such an officer, the president shall be the chief executive officer of
the corporation and shall, subject to the control of the board of directors,
have general supervision, direction and control of the business and the
officers of the corporation.  He shall preside at all meetings of the
shareholders and, in the absence of the chairman of the board, or if there be
none, at all meetings of the board of directors.  He shall have the general
powers and duties of management usually vested in the office of president of a
corporation, and shall have such other powers and duties as may be prescribed
by the board of directors or the bylaws.

         Section 8. - Vice Presidents.  In the absence or disability of the
president, the vice presidents, if any, in order of their rank as fixed by the
board of directors or, if not ranked, a vice president designated by the board
of directors, shall perform all the duties of the president, and when so acting
shall have all the powers of, and be subject to all the restrictions upon, the
president.  The vice presidents shall have such other powers and perform such
other duties as from time to time may be prescribed for them respectively by
the board of directors or the bylaws, and the president or the chairman of the
board.

         Section 9. - Secretary.  The secretary shall keep or cause to be kept,
at the principal executive office or such other place as the board of directors
may direct, a book of minutes of all meetings and actions of directors,
committees of directors and shareholders, with the time and place of holding,
whether regular or special, and, if special, how authorized, the notice given,
the names of those present at directors' meetings or committee meetings, the
number of shares present or represented at shareholders' meetings and the
proceedings.

         The secretary shall keep, or cause to be kept, at the principal
executive office or at the office of the corporation's transfer agent or
registrar, as determined by resolution of the board of directors, a share
register, or a duplicate share register, showing the names of all shareholders
and their addresses, the number and classes of shares held by each, the number
and date of certificates issued for the same and the number and date of
cancellation of every certificate surrendered for cancellation.

         The secretary shall give, or cause to be given, notice of all meetings
of the shareholders and of the board of directors required by the bylaws or by
law to be given, and he shall keep the seal of the corporation if one be
adopted, in safe custody, and shall have such other powers and perform such
other duties as may be prescribed by the board of directors or by the bylaws.





                                      -13-
   14
         Section 10. - Chief Financial Officer.  The chief financial officer
shall keep and maintain, or cause to be kept and maintained, adequate and
correct books and records of accounts of the properties and business
transactions of the corporation, including accounts of its assets, liabilities,
receipts, disbursements, gains, losses, capital, retained earnings and shares.
The books of account shall at all reasonable times be open to inspection by any
director.

         The chief financial officer shall deposit all moneys and other
valuables in the name and to the credit of the corporation with such
depositaries as may be designated by the board of directors.  He shall disburse
the funds of the corporation as may be ordered by the board of directors, shall
render to the president and directors, whenever they request it, an account of
all of his transactions as chief financial officer and of the financial
condition of the corporation, and shall have other powers and perform such
other duties as may be prescribed by the board of directors or the bylaws.


                                  ARTICLE VI.

                     INDEMNIFICATION OF DIRECTORS, OFFICERS
                           EMPLOYEES AND OTHER AGENTS

         The corporation shall have power to indemnify any person who is or was
an agent of the corporation as provided in Section 317 of the California
General Corporation Law.  The indemnification provided by this Section shall
not be deemed exclusive of any rights to which those seeking indemnification
may be entitled under any bylaw, agreement, vote of shareholders or
disinterested directors or otherwise, both as to action in an official capacity
and as to action in another capacity while holding such office, to the extent
such additional rights to indemnification are authorized in the articles of
incorporation of the corporation.  The rights to indemnity hereunder shall
continue as to a person who has ceased to be a director, officer, employee or
agent and shall inure to the benefit of the heirs, executors and administrators
of the person.

         Expenses incurred by a director of the corporation in defending a
civil or criminal action, suit or proceeding by reason of the fact that he is
or was a director of the corporation (or was serving at the corporation's
request as a director or officer of another corporation) shall be paid by the
corporation in advance of the final disposition of such action, suit or
proceeding upon receipt of an undertaking by or on behalf of such director to
repay such amount if it shall ultimately be determined that he is not entitled
to be indemnified by the corporation as authorized by relevant sections of the
California General Corporation Law.





                                      -14-
   15
                                  ARTICLE VII.

                              RECORDS AND REPORTS

         Section 1. - Maintenance and Inspection of Share Register.  The
corporation shall keep at its principal executive office, or at the office of
its transfer agent or registrar, if either be appointed and as determined by
resolution of the board of directors, a record of its shareholders, giving the
names and addresses of all shareholders and the number of classes of shares
held by each shareholder.

         A shareholder or shareholders of the corporation holding at least five
percent (5%) in the aggregate of the outstanding voting shares of the
corporation may (a) inspect and copy the records of shareholders' names and
addresses and shareholdings during usual business hours on five (5) days prior
written demand on the corporation, and (b) obtain from the transfer agent of
the corporation, on written demand and on the tender of such, shareholders'
names and addresses who are entitled to vote for the election of directors, and
their shareholdings, as of the most recent record date for which that list has
been compiled or as of a date specified by the shareholder after the date of
demand.  This list shall be made available to any shareholder by the transfer
agent on or before the later of five (5) days after the demand is received or
the date specified in the demand as the date as of which the list is to be
compiled.  The record of shareholders shall also be open to inspection on the
written demand of any shareholder or holder of a voting trust certificate, at
any time during usual business hours, for a purpose reasonably related to the
holder's interests as a shareholder or as the holder of a voting trust
certificate.  Any inspection and copying under this Section 1 may be made in
person or by an agent or attorney for the shareholder or holder of a voting
trust certificate making the demand.

         Section 2. - Maintenance and Inspection of Bylaws.  The corporation
shall keep at its principal executive office, or if its principal executive
office is not in the State of California, at its principal business office in
this state, the original or a copy of the bylaws as amended to date, which
shall be open to inspection by the shareholders at all reasonable times during
office hours.  If the principal executive office of the corporation is outside
the State of California and the corporation has no principal business office in
this state, the Secretary shall, upon the written request of any shareholder,
furnish to that shareholder a copy of the bylaws as amended to date.

         Section 3. - Maintenance and Inspection of Other Corporate Records.
The accounting books and records and minutes of proceedings of the shareholders
and the board of directors and any committee or committees of the board of
directors shall be kept at such place or places designated by the board of
directors, or, in the absence of such designation, at the principal executive
office of the corporation.  The minutes shall be kept in written form and the
accounting books and records shall be kept either in written form or in any
other form capable of being converted into written form.  The minutes and
accounting books and records shall be open to inspection upon the written
demand of any shareholder or holder of a voting trust certificate, at any
reasonable time during usual business hours,





                                      -15-
   16
for a purpose reasonably related to the holder's interests as a shareholder or
as the holder of a voting trust certificate.  The inspection may be made in
person or by an agent or attorney, and shall include the right to copy and make
extracts.  These rights of inspection shall extend to the records of each
subsidiary corporation of the corporation.

         Section 4. - Inspection by Directors.  Every director shall have the
absolute right at any reasonable time to inspect all books, records and
documents of every kind and the physical properties of the corporation and each
of its subsidiary corporations.  This inspection by a director may be made in
person or by an agent or attorney and the right of inspection includes the
right to copy and make extracts of documents.

         Section 5. - Annual Report to Shareholders.  The annual report to
shareholders referred to in Section 1501 of the California General Corporation
Law is expressly dispensed with, but nothing herein shall be interpreted as
prohibiting the board of directors from issuing annual or other periodic
reports to the shareholders of the corporation as they consider appropriate.

         Section 6. - Financial Statements.  A copy of any annual financial
statement and any income statement of the corporation for each quarterly period
of each fiscal year, and any accompanying balance sheet of the corporation as
of the end of each such period, that has been prepared by the corporation shall
be kept on file in the principal executive office of the corporation for twelve
(12) months and each such statement shall be exhibited at all reasonable times
to any shareholder demanding an examination of any such statement or a copy
shall be mailed to any such shareholder.

         If a shareholder or shareholders holding at least five percent (5%) of
the outstanding shares of any class of stock of the corporation makes a written
request to the corporation for an income statement of the corporation for the
three-month, six-month, or nine-month period of the then current fiscal year
ended more than thirty (30) days before the date of the request, and a balance
sheet of the corporation as of the end of that period, the chief financial
officer shall cause that statement to be prepared, if not already prepared, and
shall deliver personally or mail that statement or statements to the person
making the request within thirty (30) days after the receipt of the request.
If the corporation has not sent to the shareholders its annual report for the
last fiscal year, this report shall likewise be delivered or mailed to the
shareholder or shareholders within sixty (60) days after the request.

         The corporation shall also, on the written request of any shareholder,
mail to the shareholder a copy of the last annual, semi-annual or quarterly
income statement which it has prepared, and a balance sheet as of the end of
that period.

         The quarterly income statements and balance sheets referred to in this
section shall be accompanied by the report, if any, of any independent
accountants engaged by the corporation or the certificate of an authorized
officer of the corporation that the financial





                                      -16-
   17
statements were prepared without audit from the books and records of the
corporation.

         Section 7. - Annual Statement of General Information.  The corporation
shall, by the end of the calendar month of the anniversary date of its
incorporation of each year, file with the Secretary of State of the State of
California, on the prescribed form, a statement setting forth the authorized
number of directors, the names and complete business or residence addresses of
all incumbent directors, the names and complete business or residence addresses
of the chief executive officer, secretary and chief financial officer, the
street address of its principal executive officer, the street address of its
principal office or principal business office in this state, and the general
type of business constituting the principal business activity of the
corporation, together with a designation of the agent of the corporation for
the purpose of service of process, all in compliance with Section 1502 of the
California General Corporation Law.


                                 ARTICLE VIII.

                           GENERAL CORPORATE MATTERS

         Section 1. - Record Date for Purposes Other Than Notice and Voting.
For purposes of determining the shareholders entitled to receive payment of any
dividend or other distribution or allotment of any rights or entitled to
exercise any rights in respect of any other lawful action, the board of
directors may fix, in advance, a record date, which shall not be more than
sixty (60) days before any such action, and in that case only shareholders of
record on the date so fixed are entitled to receive the dividend, distribution
or allotment, or rights or to exercise the rights, as the case may be,
notwithstanding any transfer of any shares on the books of the corporation
after the record date so fixed, except as otherwise provided in the California
General Corporation Law.

         If the board of directors does not so fix a record date, the record
date for determining shareholders for any such purpose shall be at the close of
business on the day on which the board adopts the applicable resolution or the
sixtieth (60th) day before the date of that action, whichever is later.

         Section 2. - Checks, Drafts, Evidences of Indebtedness.  All checks,
drafts or other orders for payment of money, notes or other evidences of
indebtedness, issued in the name of or payable to the corporation, shall be
signed or endorsed by such person or persons and in such manner as from time to
time shall be determined by resolution of the board of directors.

         Section 3. - Corporate Contracts and Instruments; How Executed.  The
board of directors, except as otherwise provided in these bylaws, may authorize
any officer or officers, agent or agents, to enter into any contract or execute
any instrument in the name of





                                      -17-
   18
and on behalf of the corporation, and this authority may be general or confined
to specific instances; and, unless so authorized or ratified by the board of
directors or within the agency power of an officer, no officer, agent or
employee shall have any power or authority to bind the corporation by any
contract or engagement or to pledge its credit or to render it liable for any
purpose or for any amount.

         Section 4. - Certificate for Shares.  A certificate or certificates
for shares of the capital stock of the corporation shall be issued to each
shareholder when any of these shares are fully paid, and the board of directors
may authorize the issuance of certificates or shares as partly paid provided
that these certificates shall state the amount of consideration to be paid for
them and the amount paid.  All certificates shall be signed in the name of the
corporation by the chairman of the board or vice chairman of the board or the
president or vice president and by the chief financial officer or an assistant
treasurer or the secretary or any assistant secretary, certifying the number of
shares and the class or series of shares owned by the shareholder.  Any or all
of the signatures on the certificate may be facsimile.  In case any officer,
transfer agent or registrar who has signed or whose facsimile signature has
been placed on a certificate shall have ceased to be that officer, transfer
agent or registrar before that certificate is issued, it may be issued by the
corporation with the same effect as if that person were an officer, transfer
agent or registrar at the date of issue.

         Section 5. - Lost Certificates.  Except as provided in this Section 5,
no new certificates for shares shall be issued to replace an old certificate
unless the latter is surrendered to the corporation and cancelled at the same
time.  The board of directors may, in case any share certificate or certificate
for any other security is lost, stolen or destroyed, authorize the issuance of
a replacement certificate on such terms and conditions as the board may
require, including provision for indemnification of the corporation secured by
a bond or other adequate security sufficient to protect the corporation against
any claim that may be made against it, including any expense or liability, on
account of the alleged loss, theft or destruction of the certificate or the
issuance of the replacement certificate.

         Section 6. - Representation of Shares of Other Corporations.  The
chairman of the board, the president or any vice president, or any other person
authorized by resolution of the board of directors or by any of the foregoing
designated officers, is authorized to vote on behalf of the corporation any and
all shares of any other corporation or corporations, foreign or domestic,
standing in the name of the corporation.  The authority granted to these
officers to vote or represent on behalf of the corporation any and all shares
held by the corporation in any other corporation or corporations may be
exercised by any of these officers in person or by any person authorized to do
so by a proxy duly executed by these officers.

         Section 7. - Construction and Definitions.  Unless the context
requires otherwise, the general provision, rules of construction and
definitions in the California General Corporation Law shall govern the
construction of these bylaws.  Without limiting the





                                      -18-
   19
generality of this provision, the singular number includes the plural, the
plural number includes the singular, and the term "person" includes both a
corporation and a natural person.


                                  ARTICLE IX.

                                   AMENDMENTS

         Section 1. - Amendment by Shareholders.  New bylaws may be adopted or
these bylaws may be amended or repealed by the vote of holders of a majority 
of the outstanding shares entitled to vote; provided, however, that if the 
articles of incorporation of the corporation set forth the number of authorized
directors of the corporation, the authorized number of directors may be 
changed only by an amendment of the articles of incorporation.

         Section 2 - Power of Directors.  Subject to the right of shareholders
as provided in Section 1 of this Article IX to adopt, amend or repeal bylaws,
bylaws may be adopted, amended or repealed by the board of directors, provided,
however, that a bylaw or amendment thereof changing the authorized number of
directors may be adopted, amended or repealed by the board of directors only
for the purpose of fixing the exact number of directors within the limits
specified in the articles of incorporation or in Section 2 of Article III of
these bylaws.


                                   ARTICLE X.

                          LOANS OF OFFICERS AND OTHERS

         If the corporation has outstanding shares held of record by 100 or
more persons on the date of approval by the Board of Directors, the corporation
may make loans of money or property to, or guarantee the obligations of, any
officer of the corporation or its parent or any subsidiary, whether or not a
director of the corporation or its parent or any subsidiary, or adopt an
employee benefit plan or plans authorizing such loans or guaranties, upon the
approval of the Board of Directors alone, by a vote sufficient without counting
the vote of any interested director or directors, if the Board of Directors
determines that such a loan or guaranty or plan may reasonably be expected to
benefit the corporation.





                                      -19-
   20
                       CERTIFICATE OF ADOPTION OF BYLAWS



         I DO HEREBY CERTIFY AS FOLLOWS:
         That I am the duly elected, qualified and acting Secretary of Immusol,
Inc.; that the foregoing Bylaws were adopted as the bylaws of said corporation
by the unanimous written consent of the Board of Directors dated as of June 27,
1996; and that the foregoing Bylaws were approved as the bylaws of said
corporation by the shareholders of the corporation by written consent action
dated as of June 27, 1996 to be effective immediately prior to the closing of
the initial underwritten public offering.
         IN WITNESS WHEREOF, I have hereunto set my hand this ____ day of
_________, 1996.


                                        ---------------------------------------
                                        Faye H. Russell