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EXHIBIT 23.4
CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
As independent public accountants, we hereby consent to the
incorporation by reference in this Registration Statement of our report dated
January 29, 1999 on the LeukoSite, Inc. financial statements as of December 31,
1997 and 1998 and for the three years in the period ended December 31, 1998 and
to all references to our Firm included in or made part of this Registration
Statement.
/s/ Arthur Andersen LLP
Boston, Massachusetts
June 2, 2000
