Ownership Submission
FORM 3
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
  MPM BIO VENTURES I LLC
2. Date of Event Requiring Statement (Month/Day/Year)
01/19/2005
3. Issuer Name and Ticker or Trading Symbol
VIACELL INC [VIAC]
(Last)
(First)
(Middle)
C/O MPM ASSET MANAGEMENT, 111 HUNTINGTON AVENUE, 31ST FLOOR
4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
5. If Amendment, Date Original Filed(Month/Day/Year)
01/19/2005
(Street)

BOSTON, MA 02199
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Beneficially Owned
1.Title of Security
(Instr. 4)
2. Amount of Securities Beneficially Owned
(Instr. 4)
3. Ownership Form: Direct (D) or Indirect (I)
(Instr. 5)
4. Nature of Indirect Beneficial Ownership
(Instr. 5)

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 4)
2. Date Exercisable and Expiration Date
(Month/Day/Year)
3. Title and Amount of Securities Underlying Derivative Security
(Instr. 4)
4. Conversion or Exercise Price of Derivative Security 5. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 5)
6. Nature of Indirect Beneficial Ownership
(Instr. 5)
Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock Warrant   (1) 11/12/2007 Common Stock 333,333 $ 1.5 I See Footnote (2)
Common Stock Warrant   (1) 05/21/2009 Common Stock 100,000 $ 1.5 I See Footnote (2)
Series D Preferred Stock   (3)   (3) Common Stock 666,667 $ 0 (3) I See Footnote (2)
Series E Preferred Stock   (3)   (3) Common Stock 1,666,667 $ 0 (3) I See Footnote (2)
Series G Preferred Stock   (3)   (3) Common Stock 2,000,000 $ 0 (3) I See Footnote (4)
Series H Preferred Stock   (3)   (3) Common Stock 470,155 $ 0 (3) I See Footnote (5)
Series I Preferred Stock   (3)   (3) Common Stock 194,128 $ 0 (3) I See Footnote (7)
Series J Preferred Stock   (3)   (3) Common Stock 125,000 $ 0 (3) I See Footnote (6)

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
MPM BIO VENTURES I LLC
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
BB BIOVENTURES L P
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
BAB BIO VENTURES LLP
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
BAB BIO VENTURES NV
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
MPM ASSET MANAGEMENT INVESTORS 2000A LLC
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
MPM BIO VENTURES PARALLEL FUND L P
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    
MPM BIO VENTURES I LP
C/O MPM ASSET MANAGEMENT
111 HUNTINGTON AVENUE, 31ST FLOOR
BOSTON, MA 02199
    X    

Signatures

By Luke Evnin, manager of MPM BioVentures I LLC /s/ Luke Evnin 01/28/2005
**Signature of Reporting Person Date

By Ansbert Gadicke, managing director of BAB BioVentures, N.V., the general partner of BAB BioVentures L.P., the general partner of BB BioVentures L.P. /s/ Ansbert Gadicke 01/28/2005
**Signature of Reporting Person Date

By Ansbert Gadicke, managing director of BAB BioVentures, N.V., the general partner of BAB BioVentures L.P. /s/ Ansbert Gadicke 01/28/2005
**Signature of Reporting Person Date

By Ansbert Gadicke, managing director of BAB BioVentures NV /s/ Ansbert Gadicke 01/28/2005
**Signature of Reporting Person Date

By Luke Evnin, manager of MPM Asset Management Investors 2000A LLC /s/ Luke Evnin 01/28/2005
**Signature of Reporting Person Date

By Luke Evnin, manager of MPM BioVentures I LLC, the general partner of MPM BioVentures I L.P., the general partner of MPM BioVentures Parallel Fund, L.P. /s/ Luke Evnin 01/28/2005
**Signature of Reporting Person Date

By Luke Evnin, manager of MPM BioVentures I LLC, the general partner of MPM BioVentures I L.P. /s/ Luke Evnin 01/28/2005
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 5(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Immediately exercisable.
(2) The securities are held by BB BioVentures L.P.
(3) Each share of Preferred Stock will convert automatically on a 1 for 1 basis into shares of Common Stock upon the closing of Issuer's initial public offering.
(4) The shares are held as follows: 1,720,000 by BB BioVentures, L.P. ("BB BioVentures"), 260,600 by MPM BioVentures Parallel Fund, L.P. ("MPM Parallel") and 19,400 by MPM Asset Management Investors 2000A LLC ("MPM Asset"). BB BioVentures is under common control with MPM Parallel. BAB BioVentures L.P. ("BAB BV"), BAB BioVentures NV and MPM BioVentures I LLC ("BioVentures LLC") are the direct and indirect general partners of BB BioVentures. MPM BioVentures I L.P. ("BioVentures LP") and BioVentures LLC are the direct and indirect general partners of MPM Parallel. The Reporting person is a manager of MPM Investors, BioVentures LLC and MPM Asset. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.
(5) The shares are held as follows: 404,334 by BB BioVentures, 61,261 by MPM Parallel and 4,560 by MPM Asset.
(6) The shares are held as follows: 111,167 by BB BioVentures, 12,620 by MPM Parallel and 1,213 by MPM Asset.
(7) The shares are held as follows: 130,880 by MPM BioVentures II-QP, L.P. ("BV II QP"), 14,444 by MPM BioVentures II, L.P. ("BV II"), 2,715 by MPM Asset Management Investors 2001 LLC ("AM 2001") and 46,089 by MPM BioVentures GmbH & Co. Parallel-Beteiligungs KG ("BV KG"). MPM Asset Management II, L.P. ("AM II GP") and MPM Asset Management II LLC ("AM II LLC") are the direct and indirect general partners of BV II QP, BV II and BV KG. The Reporting Person is a member of AM 2001 and AM II LLC. The Reporting Person disclaims beneficial ownership of the securities except to the extent of his pecuniary interest therein.
 
Remarks:
This amendment is being filed solely to include MPM Asset Management Investors 2000A LLC which did not have EDGAR codes at the time
of filing.  See Form 3 filed for MPM BioVentures II LLC for additional members of the joint filing.

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, See Instruction 6 for procedure.

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