Filed by BioTransplant Incorporated
                                      Pursuant to Rule 425 under the Securities
                                                         Act of 1933 and deemed
                                            filed pursuant to Rule 14a-12 under
                                            the Securities Exchange Act of 1934
                                                  Subject Company: Eligix, Inc.
                                                 Commission File No.: 333-53386

This filing contains certain forward-looking statements within the meaning of
the Private Securities Litigation Reform Act of 1995. These statements are
based on management's current expectations or beliefs and are subject to a
number of factors and uncertainties that could cause actual results to differ
materially from those described in the forward-looking statements. The
forward-looking statements contained herein include, but are not limited to,
statements about future financial and operating results, the timing of the
closing of the pending merger between BioTransplant Incorporated and Eligix,
Inc. and the benefits of this merger. The following important factors, among
others, could cause actual results to differ materially from those described
in the forward-looking statements: failure of BioTransplant's or Eligix'
stockholders to approve the merger; costs related to the merger; the
difficulty the market may have in valuing the BioTransplant/Eligix business
model; the risk that BioTransplant's and Eligix' businesses will not be
integrated successfully; the failure of the combined business to realize
anticipated benefits of the merger; and other economic, business, competitive
and/or regulatory factors affecting BioTransplant's business generally,
including those factors set forth in BioTransplant's filings with the
Commission, including the registration statement on Form S-4 filed by
BioTransplant in connection with the merger and BioTransplant's most recent
annual report on Form 10-K. BioTransplant is under no obligation to, and
expressly disclaims any obligation to, update or alter its forward-looking
statements, whether as a result of new information, future events or
otherwise.

On January 8, 2001, BioTransplant filed a registration statement on Form S-4
(File No. 333-53386), which contains a joint proxy statement/prospectus, in
connection with its proposed merger with Eligix, Inc. BioTransplant will be
preparing an amendment to the registration statement and will be filing this
amendment with the Securities and Exchange Commission as soon as practicable.
The proxy statement/prospectus (when it is finalized) will be sent to
stockholders of BioTransplant seeking their approval of the proposed
transaction. A free copy of the proxy statement/prospectus and other
documents filed by BioTransplant with the Commission are available for free
at the Commission's web site at www.sec.gov. BioTransplant stockholders may
also obtain the proxy statement/prospectus and these other documents without
charge by directing a request to: BioTransplant Incorporated, Attention:
Richard Capasso, Building 75, Third Avenue, Charlestown Navy Yard,
Charlestown, MA 02129, telephone (617) 241-5200.

We urge investors and stockholders to read the proxy statement/prospectus and
any other relevant documents that BioTransplant has filed and will file with
the Securities and Exchange Commission because they contain important
information.

BioTransplant and its directors, executive officers, employees and certain
other persons may be deemed to be participants in the solicitation of proxies
from BioTransplant's stockholders to approve the proposed
BioTransplant/Eligix merger. Such individuals may have interests in the
merger, including as a result of holding options or shares of the companies.
A detailed list of the names, affiliations and interests of the participants
in the solicitation is contained in BioTransplant's proxy
statement/prospectus contained in the registration statement filed with the
Commission with respect to the proposed merger.



Set forth below is the text of certain slides used during Dr. Elliot
Lebowitz' presentation at the BIO-CEO Conference on February 21, 2001.

BIOTRANSPLANT
INCORPORATED

ELIGIX

IMPORTANT INFORMATION

This announcement contains, in addition to historical information,
forward-looking statements about BioTransplant that involve risks and
uncertainties. Such statements reflect management's current views and are
based on assumptions, including statements about the benefits of the
BioTransplant/Eligix merger, the timing of the closing of the merger and the
benefits of the merger. Actual results could differ materially from those
currently anticipated as a result of a number of important factors. Factors
that could cause future results to differ materially from such
forward-looking statements include, but are not limited to: BioTransplant's
ability to secure the substantial additional funding required for its
operations and research and development programs; failure of BioTransplant's
or Eligix's stockholders to approve the merger; the failure of the combined
business to realize anticipated benefits of the merger; the risk that, if the
merger is consummated as planned, BioTransplant's and Eligix' business will
not be integrated successfully; BioTransplant's ability to successfully
discover, develop and commercialize its products, obtain required regulatory
approvals in a timely fashion, and overcome other difficulties inherent in
developing pharmaceuticals and procedures for organ transplantation;
BioTransplant's ability to obtain and enforce the patent protection required
for its products; uncertainties to the extent of future government regulation
of the transplantation business; and BioTransplant's ability to maintain
collaborations and joint venture alliances with third parties. For a detailed
discussion of these and other factors, please refer to BioTransplant's
filings with the Securities and Exchange Commission, including the discussion
set forth in the section titled "Business - Factors Which May Affect Results"
in BioTransplant's current Annual Report on Form 10-K, as filed with the
Securities and Exchange Commission.

IMPORTANT INFORMATION

Investors and stockholders are urged to read the proxy statement/prospectus
relating to the BioTransplant/Eligix merger, filed with the Securities and
Exchange Commission by BioTransplant (File No. 333-53386), because it
contains important information. The proxy statement/prospectus will be sent
to the stockholders of BioTransplant seeking their approval of the proposed
transaction. A free copy of the proxy statement/prospectus and other
documents filed by BioTransplant with the Commission are available free at
the Commission's web site at http://www.sec.gov BioTransplant stockholders
may also obtain the proxy statement/prospectus and these other documents
without charge by directing a request to: BioTransplant Incorporated,
Attention: Richard V. Capasso, Building 75, Third Avenue, Charlestown Navy
Yard, Charlestown, MA 02129, Telephone (617) 241-5200. BioTransplant and its
directors, executive officers, employees and certain other persons may be
deemed to be participants in the solicitation of proxies from BioTransplant's
stockholders to approve the proposed BioTransplant/Eligix merger. Such
individuals may have interests in the merger, including as a result of
holding options or shares of the companies. A detailed list of the names,
affiliations and interests of the participants in the solicitation are
contained in BioTransplant's proxy statement/prospectus contained in its
registration statement filed with the Commission with respect to the proposed
merger.




BIOTRANSPLANT AND ELIGIX

 ...joining to become the industry leader
in immune modulation and human transplantation
therapy for cancer and other serious
diseases.

BIOTRANSPLANT:
TRANSITIONING TO COMMERCIALIZATION

--       JV Formed with Novartis: XenoTransplantation

--       Phase II Trials started by MedImmune: MEDI-507

--       Phase I/II Clinical Trials for AlloMune System

--       Acquisition of Eligix


BUSINESS STRATEGY:  HIGH VALUE, HIGH MARGIN PRODUCTS

I.       Major potential cash flows, no financial risk:

         -  MEDI-507                -  XenoMune

II.      Near term revenues, Phase III products

         -  B Cell-HDM              -  T Cell - HDM

III.     Clinical trials:  AlloMune family of products

IV.      Extensive preclinical pipeline


COMBINED PRODUCT PORTFOLIO

[Bar Chart]

                      PRODUCT

BioTransplant         --      MEDI-507

                               -     Bone Marrow Transplant:  Phase I/II

                               -     Psoriasis:  Phase II

                      --      AlloMune-TM-

                               -     Oncology:  Phase I/II

                               -     Solid Organ Transplant:  Phase I

                               -     Congenital Disorders:  Research/Preclinical

                               -     Autoimmune:  Research/Preclinical

                       --      XenoMune-TM-:  Research/Preclinical

Eligix                 --      B Cell-HDM:  EU Sales

                       --      T Cell-HDM:  EU Sales

                       --      PanT-HDM:  Research/Preclinical

                       --      BrCa-HDM:  Research/Preclinical

                       --      Neu/RBC-HDM:  Research/Preclinical

                       --      ReacT-HDM:  Research/Preclinical

                       --      AcTCell-HDM:  Research/Preclinical

                       --      Leuko-HDM:  Research/Preclinical




I.       CASH FLOWS WITHOUT FINANCIAL RISK

                      MEDI-507

Product:                --     Patented humanized monoclonal antibody

                        --     Positive clinical results

Indications:            --     Autoimmune disease, bone marrow and organ
                               transplant

Market Potential:       --     $350 million transplant market and much larger
                               autoimmune markets

Partner:                --     MedImmune

I.       CASH FLOWS WITHOUT FINANCIAL RISK

                       XenoMune

Product:                --     Miniature swine organs and system to enable
                               their acceptance

Indications:            --     Addresses shortage of human organs

Market Potential:       --     $5 billion

Partner:                --     Novartis joint venture

II.      COMMERICAL SALES & PHASE III PRODUCTS IN 2001

                       B Cell - HDM

Product:                --     Removes malignant B cells from bone marrow
                               transplants

Indications:            --     Prevent relapse in Non-Hodgkins' lymphoma,
                               multiple myeloma and other B cell cancers

Market Potential:       --     $150 million

II.      COMMERCIAL SALES & PHASE III PRODUCTS IN 2001

                        T Cell - HDM

Product:                --     Depletes undesirable T cells from bone marrow
                               transplants and donor leukocyte infusions

Indications:            --     Reduce GvHD in hematologic malignancies and
                               certain solid tumors

Market Potential:       --     $160 million

III.     CLINICAL TRIAL:  ALLOMUNE FAMILY OF PRODUCTS

Product:                --     Systems to re-program immune defenses with mini
                               bone marrow transplants to better:

                               -  reduce toxicity
                               -  attack cancer cells
                               -  accept transplanted donor organs

Indications:            --     Blood cell cancers and organ transplantation

Market Potential:       --     $1 billion



PRODUCT MILESTONES

[BAR CHART]

B Cell - HDM             --    CE Mark (Q1 2001)
                         --    US Cost Recovery (Q1 2001)

MEDI - 507               --    Begin Phase II Psoriasis Trials (Q1 2001)

BCell - HDM              --    Initiate Phase III Clinical Trials (Q2 2001)

TCell - HDM              --    CE Mark (Q3 2001)

AlloMune - Tx            --    Initiate Pilot Clinical Trials (Q3 2001)

Pivotal Trials

MEDI - 507               --  Initiate Clinical Trials (2002)

AlloMune - Ca            --  Initiate Clinical Trials (2002)

T Cell- HDM              --  Initiate Clinical Trials (2002)


TERMS OF THE TRANSACTION

Consideration:                            --   6.6 million BioTransplant shares

Pro Forma Ownership:                      --   Bio Transplant 66%; Eligix 34%

Accounting:                               --   Purchase

Board of Directors:                       --   Eligix to nominate 3 additional
                                               directors, one of whom will be
                                               Walter Ogier

Expected Time of Closing:                 --   Early Q2 2001


FINANCIAL STATUS

1999 Revenues                            $9.5 million

1999 Expenses                            $18.1 million

1999 Net Loss                            ($8.7) million

Cash at Year-end 2000                    $15.0 million


KEY INVESTMENT CONSIDERATIONS

--       Combined companies will become the leader in immune modulation via
         transplantation therapies

--       Creating powerful proprietary technology platforms addressing
         large underserved markets

--       Two high revenue stream products without financial risk

--       Two near term revenue products

--       Phase III products in 2001

--       Pipeline of modular, high margin products

--       Major strategic collaborations

--       Strong management team




BIOTRANSPLANT
INCORPORATED

ELIGIX

OVERVIEW OF BIOTRANSPLANT'S TECHNOLOGY


--       Proprietary set of technology to re-program the immune system

--       Allows long-term tolerance of donor cells, tissues and organs through
         transplantation

--       Applications to a wide range of medical conditions

         -        Bone Marrow and Organ transplantation

         -        Cancers

         -        Autoimmune diseases

         -        Congenital hematological disorders


IMMUNOCOGNANCE-TM- FOR FUNCTIONAL
TRANSPLANT TOLERANCE

[GRAPHIC DEPICTING BIOTRANSPLANT'S BONE MARROW CHIMERISM PROCESS]

ADVANTAGES OF BIOTRANSPLANT'S TECHNOLOGY

--       Improve clinical outcomes in bone marrow transplantation for cancer and
         other serious diseases

         -        More rapid recovery

         -        Reduced adverse effects

         -        Reduced relapse rates

         -        Superior survival and economics

--       Reduce or eliminate need for lifelong immunosuppressive therapy

         -        Reduced adverse side effects

         -        Reduced health care costs


OVERVIEW OF ELIGIX TECHNOLOGY

--       High Density Micropartilces ("HDM") with monoclonal antibodies attached
         to their surfaces

         -        Extremely selective to blood or tumor cells

--       HDM effectively removes unwanted cells

         -        Simple laboratory procedure

         -        CONSISTENT results of 99.99% or greater depletion

--       Portfolio of monoclonal antibodies

--       Applications to cancer, autoimmune diseases and transplantation.



ELIGIX HIGH DENSITY MICROPARTICLE
(HDM) TECHNOLOGY

[PHOTO DEPICTING SCIENTIST WITH SEPARATION CONTAINER, HDM-TM- REAGENT KIT,
AUTOMATED CELL PROCESSOR AND HDM-TM- TRANSFER STATION]

Separation        HMD-TM-        Automated Cell        HDM-TM-
Container       Reagent Kit      Processor             Transfer Station


EFFICIENT REMOVAL OF TARGET CELLS

--       95%+ recovery of non-target cell populations

--       4+ log reduction of target cell populations

[GRAPHIC DEPICTING TARGET CELL REMOVAL PROCESS]


ADVANTAGES OF ELIGIX TECHNOLOGY

--       Removes unwanted cells and leaves beneficial cells

--       Better yield of stem cell subsets - 90%

--       Avoids loss of important ancillary cells

--       Avoidance of cell activation

--       Ability to deplete specific T Cell subsets

--       Better depletion of tumor cells - 99.99+%




OVERVIEW OF ALLOMUNE-TM- SYSTEM

--       Integrated and proprietary set of components

--       Strong patent protection

--       Market research supports market acceptance


PROCEDURE                     CONDITION PATIENT            CONDITION TRANSPLANT

THERAPEUTIC                   MEDi-507                     ELIGIX HDM DEVICE
                                       ALLOMUNE-TM- SYSTEM


ROLE OF ELIGIX PRODUCTS IN ALLOMUNE

--      Provides key component for AlloMune

--      Minimizes graft versus host disease

        -        Avoids potentially lethal complications

        -        Expands transplant market

--      Provides standardized stem cell transplant procedure

        -        Provides more consistent clinical outcomes

        -        Enables more predictable and controlled healthcare costs