RESTATED CERTIFICATE OF INCORPORATION

EXHIBIT 3.2

RESTATED CERTIFICATE OF INCORPORATION

SANGSTAT MEDICAL CORPORATION

Pursuant to Section 245 of the General

Corporation Law of the State of Delaware

SangStat Medical Corporation, a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), does hereby certify:

1. The name of the Corporation is SangStat Medical Corporation and the date of filing of its original Certificate of Incorporation with the Secretary of State of the State of Delaware was June 2, 1995. The name under which the Corporation originally filed its Certificate of Incorporation was SangStat Delaware, Inc.

2. This Restated Certificate of Incorporation was duly adopted in accordance with the provisions of Section 245 of the General Corporation Law of the State of Delaware.

3. This Restated Certificate of Incorporation only restates and integrates and does not further amend the provisions of the Corporation’s Certificate of Incorporation as heretofore amended or supplemented, and there is no discrepancy between those provisions and the provisions of this Restated Certificate of Incorporation.

4. The text of the Restated Certificate of Incorporation of the Corporation is restated to read in its entirety as set forth below:

FIRST: The name of this Corporation is SangStat Medical Corporation.

SECOND: The address of the registered office of the Corporation in the State of Delaware is 2711 Centerville Road, Suite 400, City of Wilmington, County of New Castle, and the name of its registered agent at that address is The Prentice-Hall Corporation System, Inc.

THIRD: The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the General Corporation Law Of Delaware.

FOURTH: The Corporation is authorized to issue 45,000,000 shares, 40,000,000 of which are designated “Common Stock,” $0.001 par value, and 5,000,000 of which are designated “Preferred Stock,” $0.001 par value. The Board of Directors is hereby authorized to fix or alter the rights, preferences, privileges and restrictions granted to or imposed upon any series of Preferred Stock, and the number of shares constituting any such series and the designation thereof, or of any of them. The Board of Directors is also authorized to increase or

decrease the number of shares of any series, prior or subsequent to the issue of that series, but not below the number of shares of such series then outstanding. In case the number of shares of any series shall be so decreased, the shares constituting such decrease shall resume the status which they had prior to the adoption of the resolution originally fixing the number of shares of such series. In accordance with this Article FOURTH, the Board of Directors has designated such shares of Preferred Stock with the rights, preferences, privileges and restrictions as set forth on Exhibit A hereto.

FIFTH: In furtherance and not in limitation of the powers conferred by statute, the Board of Directors is expressly authorized to make, repeal, alter, amend and rescind from time to time any or all of the bylaws of the Corporation; provided, however, that any bylaw amendment adopted by the Board of Directors increasing or reducing the authorized number of directors or amending, repealing, altering or rescinding Article 3, Section 3.2 of the Bylaws of the Corporation shall require a resolution adopted by the affirmative vote of not less than sixty-six and two-thirds percent (66-2/3%) of the directors. Any Bylaw amendment adopted by the stockholders increasing or reducing the authorized number of directors or amending, repealing, altering or rescinding Article 3, Section 3.2 of the Bylaws of the Corporation shall require the approval of not less than sixty-six and two-thirds percent (66-2/3%) of the total voting power of all outstanding shares of stock of the Corporation entitled to vote thereon.

SIXTH: The number of directors of the Corporation shall be fixed from time to time by a Bylaw or amendment thereof duly adopted by the Board of Directors. Any director or the entire Board of Directors may be removed from office by the stockholders of the Corporation only for cause.

SEVENTH: No stockholder will be permitted to cumulate votes in any election of directors.

EIGHTH: Special meetings of the stockholders of this Corporation for any purpose or purposes may be called at any time upon the request in writing of a majority of the Board of Directors or by the Chairman of the Board or the President of the Corporation. Any such request shall state the purpose or purposes of the proposed meeting. As soon as reasonably practicable after receipt of such a request, written notice of such meeting, stating the place, date (which shall be sixty (60) days from the date of the notice) and hour of the meeting, shall be given to each stockholder entitled to vote at such meeting. Special meetings may not be called other than as provided in this ARTICLE EIGHTH.

NINTH: Stockholders of the Corporation shall take action by meetings held pursuant to this Restated Certificate of Incorporation and the Bylaws. Stockholders may not take any action by written consent in lieu of a meeting. Meetings of stockholders may be held within or outside of the State of Delaware, as the Bylaws may provide. The books of the Corporation may be kept (subject to any provision contained in the statute) outside the State of Delaware at such place or places as may be designated from time to time by the Board of Directors or in the Bylaws of the Corporation.

TENTH: The Corporation reserves the right to amend, alter, change or repeal any provision contained in this Restated Certificate of Incorporation, in the manner now or hereafter

prescribed by statute, and all rights conferred on stockholders herein are granted subject to this reservation. Notwithstanding the foregoing, the provisions set forth in ARTICLES FIFTH, SIXTH, NINTH, ELEVENTH and this ARTICLE TENTH may not be repealed or amended in any respect unless such repeal or amendment is approved by the affirmative vote of not less than sixty-six and two-thirds percent (66-2/3%) of the total voting power of all outstanding shares of stock of this Corporation entitled to vote thereon, unless such amendment or repeal has been previously approved by the vote of not less than sixty-six and two-thirds percent (66-2/3%) of the members of the Board of Directors, in which case those Articles of this Restated Certificate of Incorporation may be so amended or repealed by a vote of not less than a majority of the total voting power of all outstanding shares of stock of the Corporation entitled to vote thereon.

ELEVENTH: A director of the Corporation shall not be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director’s duty of loyalty to the Corporation or its stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv) for any transaction from which the director derived any improper personal benefit. If the Delaware General Corporation Law is hereafter amended to authorize, with the approval of a corporation’s stockholder, further reductions in the liability of the directors of a corporation for breach of fiduciary duty, then a director of the Corporation shall not be liable for any such breach to the fullest extent permitted by the Delaware General Corporation Law as so amended. Any repeal or modification of the foregoing provisions of this ARTICLE ELEVENTH by the stockholders of the Corporation shall not adversely affect any right or protection of a director of the Corporation existing at the time of such repeal or modification.

TWELFTH: Elections of directors need not be by written ballot unless the Bylaws of the Corporation shall so provide.

IN WITNESS WHEREOF, the Corporation has caused this Restated Certificate of Incorporation to be executed on its behalf this 8th day of July, 2002.

	SANGSTAT MEDICAL CORPORATION

	By:	/s/ Stephen G. Dance
		Stephen G. Dance
		Senior Vice President, Finance

EXHIBIT A

CERTIFICATE OF DESIGNATIONS

SERIES A JUNIOR PARTICIPATING PREFERRED STOCK

SANGSTAT MEDICAL CORPORATION

Pursuant to Section 151 of the General

Corporation Law of the State of Delaware

SangStat Medical Corporation, a corporation organized and existing under the General Corporation Law of the State of Delaware (hereinafter called the “Corporation”), hereby certifies that the following resolution was adopted by the Board of Directors of the Corporation as required by Section 151 of the General Corporation Law at a meeting duly called and held on July 26, 1995:

RESOLVED, that pursuant to the authority granted to and vested in the Board of Directors of the Corporation (hereinafter called the “Board of Directors” or the “Board”) in accordance with the provisions of the Certificate of Incorporation, the Board of Directors hereby creates a series of Preferred Stock, par value $.001 per share (the “Preferred Stock”), of the Corporation and hereby states the designation and number of shares, and fixes the relative rights, preferences, and limitations thereof as follows:

Series A Junior Participating Preferred Stock:

Section 1. Designation and Amount. The shares of such series shall be designated as “Series A Junior Participating Preferred Stock” (the “Series A Preferred Stock”) and the number of shares constituting the Series A Preferred Stock shall be Five Hundred Thousand (500,000). Such number of shares may be increased or decreased by resolution of the Board of Directors; provided, that no decrease shall reduce the number of shares of Series A Preferred Stock to a number less than the number of shares then outstanding plus the number of shares reserved for issuance upon the exercise of outstanding options, rights or warrants or upon the conversion of any outstanding securities issued by the Corporation convertible into Series A Preferred Stock.

Section 2. Dividends and Distributions.

(A) Subject to the rights of the holders of any shares of any series of Preferred Stock (or any similar stock) ranking prior and superior to the Series A Preferred Stock with respect to dividends, the holders of shares of Series A Preferred Stock, in preference to the holders of the Common Stock, par value $.001 per share (the “Common Stock”), of the Corporation, and of any other

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junior stock, shall be entitled to receive, when, as and if declared by the Board of Directors out of funds legally available for the purpose, quarterly dividends payable in cash on the first day of March, June, September and December in each year (each such date being referred to herein as a “Quarterly Dividend Payment Date”), commencing on the first Quarterly Dividend Payment Date after the first issuance of a share or fraction of a share of Series A Preferred Stock, in an amount per share (rounded to the nearest cent) equal to, subject to the provision for adjustment hereinafter set forth, 100 times the aggregate per share amount of all cash dividends, and 100 times the aggregate per share amount (payable in kind) of all non-cash dividends or other distributions, other than a dividend payable in shares of Common Stock or a subdivision of the outstanding shares of Common Stock (by reclassification or otherwise), declared on the Common Stock since the immediately preceding Quarterly Dividend Payment Date or, with respect to the first Quarterly Dividend Payment Date, since the first issuance of any share or fraction of a share of Series A Preferred Stock. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision or combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the amount to which holders of shares of Series A Preferred Stock were entitled immediately prior to such event under clause (b) of the preceding sentence shall be adjusted by multiplying such amount by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

(B) The Corporation shall declare a dividend or distribution on the Series A Preferred Stock as provided in paragraph (A) of this Section immediately after it declares a dividend or distribution on the Common Stock (other than a dividend payable in shares of Common Stock).

(C) Dividends shall begin to accrue and be cumulative on outstanding shares of Series A Preferred Stock from the Quarterly Dividend Payment Date next preceding the date of issue of such shares, unless the date of issue of such shares is prior to the record date for the first Quarterly Dividend Payment Date, in which case dividends on such shares shall begin to accrue from the date of issue of such shares, or unless the date of issue is a Quarterly Dividend Payment Date or is a date after the record date for the determination of holders of shares of Series A Preferred Stock entitled to receive a quarterly dividend and before such Quarterly Dividend Payment Date, in either of which events such dividends shall begin to accrue and be cumulative from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not bear interest. Dividends paid on the shares of Series A Preferred Stock in an amount less than the total amount of such dividends at the time accrued and payable on such shares shall be allocated pro rata on a share-by-share basis among all such shares at the time outstanding. The Board of Directors may fix a record date for the determination of holders of

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shares of Series A Preferred Stock entitled to receive payment of a dividend or distribution declared thereon, which record date shall be not more than 60 days prior to the date fixed for the payment thereof.

Section 3. Voting Rights. The holders of shares of Series A Preferred Stock shall have the following voting rights:

(A) Subject to the provision for adjustment hereinafter set forth, each share of Series A Preferred Stock shall entitle the holder thereof to 100 votes on all matters submitted to a vote of the stockholders of the Corporation. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision or combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the number of votes per share to which holders of shares of Series A Preferred Stock were entitled immediately prior to such event shall be adjusted by multiplying such number by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

(B) Except as otherwise provided herein, in any other Certificate of Designations creating a series of Preferred Stock or any similar stock, or by law, the holders of shares of Series A Preferred Stock and the holders of shares of Common Stock and any other capital stock of the Corporation having general voting rights shall vote together as one class on all matters submitted to a vote of stockholders of the Corporation.

(C) Except as set forth herein, or as otherwise provided by law, holders of Series A Preferred Stock shall have no special voting rights and their consent shall not be required (except to the extent they are entitled to vote with holders of Common Stock as set forth herein) for taking any corporate action.

Section 4. Certain Restrictions.

(A) Whenever quarterly dividends or other dividends or distributions payable on the Series A Preferred Stock as provided in Section 2 are in arrears, thereafter and until all accrued and unpaid dividends and distributions, whether or not declared, on shares of Series A Preferred Stock outstanding shall have been paid in full, the Corporation shall not:

(i) declare or pay dividends, or make any other distributions, on any shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the Series A Preferred Stock;

(ii) declare or pay dividends, or make any other distributions, on any shares of stock ranking on a parity (either as to dividends or upon

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liquidation, dissolution or winding up) with the Series A Preferred Stock, except dividends paid ratably on the Series A Preferred Stock and all such parity stock on which dividends are payable or in arrears in proportion to the total amounts to which the holders of all such shares are then entitled;

(iii) redeem or purchase or otherwise acquire for consideration shares of any stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the Series A Preferred Stock, provided that the Corporation may at any time redeem, purchase or otherwise acquire shares of any such junior stock in exchange for shares of any stock of the Corporation ranking junior (either as to dividends or upon dissolution, liquidation or winding up) to the Series A Preferred Stock; or

(iv) redeem or purchase or otherwise acquire for consideration any shares of Series A Preferred Stock, or any shares of stock ranking on a parity with the Series A Preferred Stock, except in accordance with a purchase offer made in writing or by publication (as determined by the Board of Directors) to all holders of such shares upon such terms as the Board of Directors, after consideration of the respective annual dividend rates and other relative rights and preferences of the respective series and classes, shall determine in good faith will result in fair and equitable treatment among the respective series or classes.

(B) The Corporation shall not permit any subsidiary of the Corporation to purchase or otherwise acquire for consideration any shares of stock of the Corporation unless the Corporation could, under paragraph (A) of this Section 4, purchase or otherwise acquire such shares at such time and in such manner.

Section 5. Reacquired Shares. Any shares of Series A Preferred Stock purchased or otherwise acquired by the Corporation in any manner whatsoever shall be retired and cancelled promptly after the acquisition thereof. All such shares shall upon their cancellation become authorized but unissued shares of Preferred Stock and may be reissued as part of a new series of Preferred Stock subject to the conditions and restrictions on issuance set forth herein, in the Certificate of Incorporation, or in any other Certificate of Designations creating a series of Preferred Stock or any similar stock or as otherwise required by law.

Section 6. Liquidation, Dissolution or Winding Up. Upon any liquidation, dissolution or winding up of the Corporation, no distribution shall be made (1) to the holders of shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the Series A Preferred Stock unless, prior thereto, the holders of shares of Series A Preferred Stock shall have received $100 per share, plus an amount equal to accrued and unpaid dividends and distributions thereon, whether or not declared, to the date of such payment, provided that the holders of shares of Series A Preferred Stock shall be entitled to receive an aggregate amount per share, subject to the provision for adjustment hereinafter set forth, equal to 100 times the aggregate amount to be distributed per share to holders of shares of Common Stock, or

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(2) to the holders of shares of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or winding up) with the Series A Preferred Stock, except distributions made ratably on the Series A Preferred Stock and all such parity stock in proportion to the total amounts to which the holders of all such shares are entitled upon such liquidation, dissolution or winding up. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision or combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the aggregate amount to which holders of shares of Series A Preferred Stock were entitled immediately prior to such event under the proviso in clause (1) of the preceding sentence shall be adjusted by multiplying such amount by a fraction the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

Section 7. Consolidation, Merger, etc. In case the Corporation shall enter into any consolidation, merger, combination or other transaction in which the shares of Common Stock are exchanged for or changed into other stock or securities, cash and/or any other property, then in any such case each share of Series A Preferred Stock shall at the same time be similarly exchanged or changed into an amount per share, subject to the provision for adjustment hereinafter set forth, equal to 100 times the aggregate amount of stock, securities, cash and/or any other property (payable in kind) as the case may be, into which or for which each share of Common Stock is changed or exchanged. In the event the Corporation shall at any time declare or pay any dividend on the Common Stock payable in shares of Common Stock, or effect a subdivision or combination or consolidation of the outstanding shares of Common Stock (by reclassification or otherwise than by payment of a dividend in shares of Common Stock) into a greater or lesser number of shares of Common Stock, then in each such case the amount set forth in the preceding sentence with respect to the exchange or change of shares of Series A Preferred Stock shall be adjusted by multiplying such amount by a fraction, the numerator of which is the number of shares of Common Stock outstanding immediately after such event and the denominator of which is the number of shares of Common Stock that were outstanding immediately prior to such event.

Section 8. No Redemption. The shares of Series A Preferred Stock shall not be redeemable.

Section 9. Rank. The Series A Preferred Stock shall rank, with respect to the payment of dividends and the distribution of assets, junior to all series of any other class of the Corporation’s Preferred Stock.

Section 10. Amendment. The Certificate of Incorporation of the Corporation shall not be amended in any manner which would materially alter or change the powers, preferences or special rights of the Series A Preferred Stock so as to affect them adversely without the affirmative vote of the holders of at least a majority of the outstanding shares of Series A Preferred Stock, voting together as a single class.

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