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                                                                     Exhibit 3.3



                AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

                                       OF

                                 ATHERSYS, INC.

                                    ARTICLE I

     The name of the corporation is Athersys, Inc. (the "Company").

                                   ARTICLE II

     The address of the Company's registered office in the State of Delaware is
Corporation Trust Center, 1209 Orange Street, City of Wilmington, County of New
Castle, Delaware 19801. The name of the Company's registered agent at such
address is The Corporation Trust Company.

                                   ARTICLE III

     The purpose of the Company is to engage in any lawful act or activity for
which corporations may be organized under the General Corporation Law of the
State of Delaware, as amended (the "DGCL").

                                   ARTICLE IV

     Section 1. Authorized Capital Stock. The Company is authorized to issue two
classes of capital stock, designated Common Stock and Preferred Stock. The total
number of shares of capital stock that the Company is authorized to issue is
165,500,000 shares, consisting of 150,000,000 shares of common stock, par value
$0.01 per share, and 15,000,000 shares of preferred stock, par value $0.01 per
share.

     Section 2. Preferred Stock. The Preferred Stock may be issued in one or
more series. The Board of Directors of the Company (the "Board") is hereby
authorized to issue the shares of Preferred Stock in such series and to fix from
time to time before issuance the number of shares to be included in any such
series and the designation, relative powers, preferences, rights and
qualifications, limitations or restrictions of such series. The authority of the
Board with respect to each such series will include, without limiting the
generality of the foregoing, the determination of any or all of the following:

          (a) the number of shares of any series and the designation to
     distinguish the shares of such series from the shares of all other series;

          (b) the voting powers, if any, and whether such voting powers are full
     or limited in such series;


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          (c) the redemption provisions, if any, applicable to such series,
     including the redemption price or prices to be paid;

          (d) whether dividends, if any, will be cumulative or noncumulative,
     the dividend rate of such series, and the dates and preferences of
     dividends on such series;

          (e) the rights of such series upon the voluntary or involuntary
     dissolution of, or upon any distribution of the assets of, the Company;

          (f) the provisions, if any, pursuant to which the shares of such
     series are convertible into, or exchangeable for, shares of any other class
     or classes or of any other series of the same or any other class or classes
     of stock, or any other security, of the Company or any other corporation or
     other entity and the rates or other determinants of conversion or exchange
     applicable thereto;

          (g) the right, if any, to subscribe for or to purchase any securities
     of the Company or any other corporation or other entity;

          (h) the provisions, if any, of a sinking fund applicable to such
     series; and

          (i) any other relative, participating, optional or other special
     powers, preferences or rights and qualifications, limitations or
     restrictions thereof;

all as may be determined from time to time by the Board and stated or expressed
in the resolution or resolutions providing for the issuance of such Preferred
Stock (collectively, a "Preferred Stock Designation").

          Section 3. Common Stock. Subject to the rights of the holders of any
series of Preferred Stock, the holders of Common Stock will be entitled to one
vote on each matter submitted to a vote at a meeting of stockholders for each
share of Common Stock held of record by such holder as of the record date for
such meeting.

                                    ARTICLE V

          The Board may make, amend, and repeal the Bylaws of the Company. Any
Bylaw made by the Board under the powers conferred hereby may be amended or
repealed by the Board (except as specified in any such Bylaw so made or amended)
or by the stockholders in the manner provided in the Bylaws of the Company.
Notwithstanding the foregoing and anything contained in this Certificate of
Incorporation or the Bylaws to the contrary, Bylaws 1, 3, 8, 10, 11, 12, 13, and
36 may not be amended or repealed by the stockholders, and no provision
inconsistent therewith may be adopted by the stockholders, without the
affirmative vote of the holders of at least 80% of the voting power of the
outstanding Voting Stock (as defined below), voting together as a single class.
The Company may in its Bylaws confer powers upon the Board in addition to the
foregoing and in addition to the powers and authorities expressly conferred upon
the Board by applicable law. For the purposes of this Certificate of
Incorporation, "Voting Stock" means stock of the Company of any class or series
entitled to vote generally in the election of the directors of the Board (the
"Directors"). Notwithstanding anything contained in this Certificate of
Incorporation to the contrary, the affirmative vote of the holders of at least

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80% of the Voting Stock, voting together as a single class, is required to amend
or repeal, or to adopt any provisions inconsistent with, this Article V.

                                   ARTICLE VI

     Subject to the rights of the holders of any series of Preferred Stock:

          (a) any action required or permitted to be taken by the stockholders
     of the Company must be effected at a duly called annual or special meeting
     of stockholders of the Company and may not be effected by any consent in
     writing of such stockholders; and

          (b) special meetings of stockholders of the Company may be called only
     by (i) the Chairman of the Board (the "Chairman"), (ii) the President of
     the Company (the "President") or (iii) the Secretary of the Company (the
     "Secretary") within 10 calendar days after receipt of the written request
     of a majority of the total number of Directors that the Company would have
     if there were no vacancies (the "Whole Board").

At any annual meeting or special meeting of stockholders of the Company, only
such business will be conducted or considered as has been brought before such
meeting in the manner provided in the Bylaws of the Company. Notwithstanding
anything contained in this Certificate of Incorporation to the contrary, the
affirmative vote of the holders of at least 80% of the voting power of the
outstanding Voting Stock, voting together as a single class, will be required to
amend or repeal, or adopt any provision inconsistent with, this Article VI.

                                   ARTICLE VII

     Section 1. Number, Election, and Terms of Directors. Subject to the rights,
if any, of the holders of any series of Preferred Stock to elect additional
Directors under circumstances specified in a Preferred Stock Designation, the
number of the Directors of the Company will not be less than six nor more than
nine and will be fixed from time to time in the manner provided in the Bylaws of
the Company. The Directors, other than those who may be elected by the holders
of any series of Preferred Stock, will be classified with respect to the time
for which they severally hold office into three classes, as nearly equal in
number as possible, designated Class I, Class II, and Class III. At any meeting
of stockholders at which Directors are to be elected, the number of Directors
elected may not exceed the greatest number of Directors then in office in any
class of Directors. The Directors first appointed to Class I will hold office
for a term expiring at the annual meeting of stockholders to be held in 2001;
the Directors first appointed to Class II will hold office for a term expiring
at the annual meeting of stockholders to be held in 2002; and the Directors
first appointed to Class III will hold office for a term expiring at the annual
meeting of stockholders to be held in 2003, with the members of each class to
hold office until their successors are elected and qualified. At each succeeding
annual meeting of the stockholders of the Company, the successors to the class
of Directors whose term expires at that meeting will be elected by plurality
vote of all votes cast at such meeting to hold office for a term expiring at the
annual meeting of stockholders held in the third year following the year of
their election. Subject to the rights, if any, of the holders of any series of
Preferred Stock to elect additional Directors under circumstances specified in a
Preferred Stock Designation, Directors may be elected by the stockholders only
at an annual meeting of stockholders. Election of


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Directors of the Company need not be by written ballot unless requested by the
Chairman or by the holders of a majority of the Voting Stock present in person
or represented by proxy at a meeting of the stockholders at which Directors are
to be elected. If authorized by the Board, such requirement of written ballot
shall be satisfied by a ballot submitted by electronic transmission, provided
that any such electronic transmission must either set forth or be submitted with
information from which it can be determined that the electronic transmission was
authorized by the stockholder or proxy holder.

     Section 2. Nomination of Director Candidates. Advance notice of stockholder
nominations for the election of Directors must be given in the manner provided
in the Bylaws of the Company.

     Section 3. Newly Created Directorships and Vacancies. Subject to the
rights, if any, of the holders of any series of Preferred Stock to elect
additional Directors under circumstances specified in a Preferred Stock
Designation, newly created directorships resulting from any increase in the
number of Directors and any vacancies on the Board resulting from death,
resignation, disqualification, removal, or other cause will be filled solely by
the affirmative vote of a majority of the remaining Directors then in office,
even though less than a quorum of the Board, or by a sole remaining Director.
Any Director elected in accordance with the preceding sentence will hold office
for the remainder of the full term of the class of Directors in which the new
directorship was created or the vacancy occurred and until such Director's
successor has been elected and qualified. No decrease in the number of Directors
constituting the Board may shorten the term of any incumbent Director.

     Section 4. Removal. Subject to the rights, if any, of the holders of any
series of Preferred Stock to elect additional Directors under circumstances
specified in a Preferred Stock Designation, any Director may be removed from
office by the stockholders only for cause and only in the manner provided in
this Article VII, Section 4. At any annual meeting or special meeting of the
stockholders, the notice of which states that the removal of a Director or
Directors is among the purposes of the meeting, the affirmative vote of the
holders of at least 80% of the voting power of the outstanding Voting Stock,
voting together as a single class, may remove such Director or Directors for
cause.

     Section 5. Amendment, Repeal, Etc. Notwithstanding anything contained in
this Certificate of Incorporation to the contrary, the affirmative vote of the
holders of at least 80% of the voting power of the outstanding Voting Stock,
voting together as a single class, is required to amend or repeal, or adopt any
provision inconsistent with, this Article VII. The amendment or repeal of, or
the adoption of any provision inconsistent with, this Article VII must be by
written ballot.

                                  ARTICLE VIII

     To the full extent permitted by the Delaware General Corporation Law or any
other applicable law currently or hereafter in effect, no Director of the
Company will be personally liable to the Company or its stockholders for or with
respect to any acts or omissions in the performance of his or her duties as a
Director of the Company. Any repeal or modification of this Article VIII will
not adversely affect any right or protection of a Director of the Company
existing prior to such repeal or modification.


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                                   ARTICLE IX

         Section 1. Right to Indemnification. Each person who was or is made a
party or is threatened to be made a party to or is otherwise involved in any
action, suit or proceeding, whether civil, criminal, administrative or
investigative (a "Proceeding"), by reason of the fact that he or she is or was a
director or an officer of the Company or is or was serving at the request of the
Company as a director, officer, employee or agent of another company or of a
partnership, joint venture, trust or other enterprise, including service with
respect to an employee benefit plan (an "Indemnitee"), whether the basis of such
Proceeding is alleged action in an official capacity as a director, officer,
employee or agent or in any other capacity while serving as a director, officer,
employee or agent, shall be indemnified and held harmless by the Company to the
fullest extent permitted or required by the Delaware General Corporation Law, as
the same exists or may hereafter be amended (but, in the case of any such
amendment, only to the extent that such amendment permits the Company to provide
broader indemnification rights than such law permitted the Company to provide
prior to such amendment), against all expense, liability and loss (including
attorneys' fees, judgments, fines, ERISA excise taxes or penalties and amounts
paid in settlement) reasonably incurred or suffered by such Indemnitee in
connection therewith; provided, however, that, except as provided in Section 3
of this Article IX with respect to Proceedings to enforce rights to
indemnification, the Company shall indemnify any such Indemnitee in connection
with a Proceeding (or part thereof) initiated by such Indemnitee only if such
Proceeding (or part thereof) was authorized by the Board of Directors of the
Company.

         Section 2. Right to Advancement of Expenses. The right to
indemnification conferred in Section 1 of this Article IX shall include the
right to be paid by the Company the expenses (including, without limitation,
attorneys' fees and expenses) incurred in defending any such Proceeding in
advance of its final disposition (an "Advancement of Expenses"); provided,
however, that, if the Delaware General Corporation Law so requires, an
Advancement of Expenses incurred by an Indemnitee in his or her capacity as a
director or officer (and not in any other capacity in which service was or is
rendered by such Indemnitee, including, without limitation, service to an
employee benefit plan) shall be made only upon delivery to the Company of an
undertaking (an "Undertaking"), by or on behalf of such Indemnitee, to repay all
amounts so advanced if it shall ultimately be determined by final judicial
decision from which there is no further right to appeal (a "Final Adjudication")
that such Indemnitee is not entitled to be indemnified for such expenses under
this Section 2 or otherwise. The rights to indemnification and to the
Advancement of Expenses conferred in Sections 1 and 2 of this Article IX shall
be contract rights and such rights shall continue as to an Indemnitee who has
ceased to be a director, officer, employee or agent and shall inure to the
benefit of the Indemnitee's heirs, executors and administrators.

         Section 3. Right of Indemnitee to Bring Suit. If a claim under Section
1 or 2 of this Article IX is not paid in full by the Company within 60 calendar
days after a written claim has been received by the Company, except in the case
of a claim for an Advancement of Expenses, in which case the applicable period
shall be 20 calendar days, the Indemnitee may at any time thereafter bring suit
against the Company to recover the unpaid amount of the claim. If successful in
whole or in part in any such suit, or in a suit brought by the Company to
recover an Advancement of Expenses pursuant to the terms of an Undertaking, the
Indemnitee shall be enti tled to be paid also the expense of prosecuting or
defending such suit. In (i) any suit brought by the Indemnitee to enforce a
right to indemnification hereunder (but not in a suit brought by the


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Indemnitee to enforce a right to an Advancement of Expenses) it shall be a
defense that, and (ii) any suit brought by the Company to recover an Advancement
of Expenses pursuant to the terms of an Undertaking, the Company shall be
entitled to recover such expenses upon a Final Adjudication that, the Indemnitee
has not met any applicable standard for indemnification set forth in the
Delaware General Corporation Law. Neither the failure of the Company (including
its Board of Directors, independent legal counsel or stockholders) to have made
a determination prior to the commencement of such suit that indemnification of
the Indemnitee is proper in the circumstances because the Indemnitee has met the
applicable standard of conduct set forth in the Delaware General Corporation
Law, nor an actual determination by the Company (including its Board of
Directors, independent legal counsel or stockholders) that the Indemnitee has
not met such applicable standard of conduct, shall create a presumption that the
Indemnitee has not met the applicable standard of conduct or, in the case of
such a suit brought by the Indemnitee, be a defense to such suit. In any suit
brought by the Indemnitee to enforce a right to indemnification or to an
Advancement of Expenses hereunder, or brought by the Company to recover an
Advancement of Expenses pursuant to the terms of an Undertaking, the burden of
proving that the Indemnitee is not entitled to be indemnified, or to such
Advancement of Expenses, under this Article IX or otherwise shall be on the
Company.

         Section 4. Non-Exclusivity of Rights. The rights to indemnification and
to the Advancement of Expenses conferred in this Article IX shall not be
exclusive of any other right which any person may have or hereafter acquire
under any statute, the Company's Certificate of Incorporation, By-laws,
agreement, vote of stockholders or disinterested directors or otherwise.

         Section 5. Insurance. The Company may maintain insurance, at its
expense, to protect itself and any director, officer, employee or agent of the
Company or another corporation, partnership, joint venture, trust or other
enterprise against any expense, liability or loss, whether or not the Company
would have the power to indemnify such person against such expense, liability or
loss under the Delaware General Corporation Law.

         Section 6. Indemnification of Employees and Agents of the Company. The
Company may, to the extent authorized from time to time by the Board of
Directors, grant rights to indemnification and to the Advancement of Expenses to
any employee or agent of the Company to the fullest extent of the provisions of
this Article IX with respect to the indemnification and Advancement of Expenses
of directors and officers of the Company.




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