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[LAZARD LOGO] LAZARD FRERES & CO. LLC
30 ROCKEFELLER PLAZA
NEW YORK, NY 10020
PHONE 212-632-6000
FAX 212-632-6060
www.lazard.com
EXHIBIT 23.5
We hereby consent to the inclusion of our opinion letter dated December
8, 2000 to the board of directors of BioTransplant Incorporated as Annex C to
this joint proxy statement/prospectus which forms part of the Registration
Statement on Form S-4 relating to the proposed merger of Eligix, Inc. with a
subsidiary of BioTransplant and the references to such opinion in such joint
proxy statement/prospectus under the headings "Summary--Opinion of Financial
Advisor," "The Merger--Background of the Merger," "The Merger--Recommendation
of the Board of Directors of BioTransplant; BioTransplant's Reasons for the
Merger" and "The Merger--Opinion of BioTransplant's Financial Advisor." In
giving such consent, we do not admit, and we hereby disclaim, that we come
within the category of persons whose consent is required under Section 7 of
the Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission promulgated thereunder, nor do we thereby
admit that we are experts with respect to any part of the Registration
Statement within the meaning of the terms "experts" as used in the Securities
Act of 1933, as amended, or the rules and regulations of the Securities and
Exchange Commission promulgated thereunder.
Lazard Freres & Co. LLC
By: /s/ Stephen H. Sands
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Name: Stephen H. Sands
Title: Managing Director
January 5, 2001
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