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EXHIBIT 23.1

CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS

        We consent to the incorporation by reference in the Registration Statements (Form S-8) pertaining to the 1996 Equity Incentive Plan, Employee Stock Purchase Plan, 1998 Non-Officer Stock Option Plan and 1999 Equity Incentive Plan, and Registration Statements on Form S-3 (Nos. 333-93481, 333-47224, 333-61460, 333-61910 and 333-67286), of Cerus Corporation of our report dated January 30, 2003 with respect to the financial statements of Cerus Corporation included in its Annual Report (Form 10-K) for the year ended December 31, 2002, filed with the Securities and Exchange Commission.

Palo Alto, California March 25, 2003

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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS