<PAGE>
                                                                     EXHIBIT 4.4

NEITHER THIS WARRANT NOR THE SECURITIES ISSUABLE UPON EXERCISE OF THIS WARRANT
HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. NO SALE OR
DISPOSITION MAY BE EFFECTED EXCEPT IN COMPLIANCE WITH RULE 144 UNDER SAID ACT OR
WITHOUT AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO OR AN OPINION OF
COUNSEL FOR 'THE HOLDER, SATISFACTORY TO THE COMPANY, THAT SUCH REGISTRATION IS
NOT REQUIRED UNDER THE ACT OR RECEIPT, OF A NO-ACTION LETTER FROM THE SECURITIES
AND EXCHANGE COMMISSION.

          WARRANT TO PURCHASE 18,750 SHARES OF SERIES J PREFERRED STOCK


                                          October 16, 2003


THIS CERTIFIES THAT, for value received, General Electric Capital Corporation
("Holder") is entitled to subscribe for and purchase Eighteen Thousand Seven
Hundred Fifty (18,750) shares of the fully paid and nonassessable Series J
Preferred Stock (the "Shares" or the "Preferred Stock") of Viacell, Inc., a
Delaware corporation (the "Company"), at the Warrant Price (as hereinafter
defined), subject to the provisions and upon the terms and conditions
hereinafter set forth. As used herein, the term "Series J Preferred Stock" shall
mean the Company's presently authorized Series J Preferred Stock and any stock
into which such Series J Preferred Stock may hereafter be converted or
exchanged.

1. Warrant Price. The Warrant Price shall initially be Eight and 00/100 dollars
($8.00) per share, subject to adjustment as provided in Section 7 below.

2. Conditions to Exercise. The purchase right represented by this Warrant may be
exercised at any time, or from time to time, in whole or in part during the term
commencing on the date hereof and ending at 5:00 P.M. Pacific time on the tenth
anniversary of the date of this Warrant.

3. Method of Exercise, Payment; Issuance of Shares; Issuance of New Warrant.

      (a) Cash Exercise. Subject to Section 2 hereof, the purchase right
represented by this Warrant may be exercised by the Holder hereof, in whole or
in part, by the surrender of this Warrant (with a duly executed Notice of
Exercise in the form attached hereto) at the principal office of the Company (as
set forth in Section 18 below) and by payment to the Company, by check, of an
amount: equal to the then applicable Warrant Price per share multiplied by the
number of shares then being purchased. In the event of any exercise of the
rights represented by this Warrant, certificates for the shares of stock so
purchased shall be in the name of, and delivered to, the Holder hereof, or as
such Holder may direct (subject to the terms of transfer contained herein and
upon payment by such Holder hereof of any applicable transfer taxes). Such
delivery shall be made within 30 days after exercise of the Warrant and at the
Company's expense and, unless this Warrant has been fully exercised or expired,
a new Warrant having terms and conditions substantially identical to this
Warrant and representing the portion of the Shares, if any, with respect to
which this Warrant shall not have been exercised, shall also be issued to the
Holder hereof within 30 days after exercise of the Warrant.
<PAGE>
      (b) Net Issue Exercise. Holder may also elect to receive shares equal to
the value of this Warrant (or of any portion thereof remaining unexercised) by
surrender of this Warrant at the principal office of the Company together with
notice of such election, in which event the Company shall issue to Holder the
number of shares of the Company's Preferred Stock computed using the following
formula:

            X = Y (A-B)
                -------
                   A

            Where X = the number of shares of Preferred Stock to be issued to
            Holder.

            Y = the number of shares of Preferred Stock purchasable under this
            Warrant (at the date of such calculation).

            A = the Fair Market Value of one share of the Company's Preferred
            Stock (at the date of such calculation).

            B = Warrant Price (as adjusted to the date of such calculation).

      (c) Fair Market Value. For purposes of this Section 3, Fair Market Value
of one share of the Company's Preferred Stock shall mean:

            (i) In the event of an exercise in connection with an Initial Public
      Offering, the per share Fair Market Value for the Preferred Stock shall be
      the Offering Price at which the underwriters initially sell Common Stock
      to the public multiplied by the number of shares of Common Stock into
      which each share of Preferred Stock is then convertible; or

            (ii) The average of the closing bid and asked prices of Common Stock
      quoted in the Over-The-Counter Market Summary, the last reported sale
      price quoted on the Nasdaq National Market ("NNM") or on any exchange on
      which the Common Stock is listed, whichever is applicable, as published in
      the Western Edition of the Wall Street Journal for the ten (10) trading
      days prior to the date of determination of Fair Market Value, multiplied
      by the number of shares of Common Stock into which each share of Preferred
      Stock is then convertible; or

            (iii) In the event of an exercise in connection with a merger,
      acquisition or other consolidation in which the Company is not the
      surviving entity, the per share Fair Market Value for the Preferred Stock
      shall be the value to be received per share of Preferred Stock by all
      holders of the Preferred Stock in such transaction as determined by the
      Board of Directors; or

            (iv) In any other instance, the per share Fair Market Value for the
      Preferred Stock shall be as determined in good faith by the Company's
      Board of Directors. In the event of 3(c)(iii) or 3(c)(iv), above, the
      Company's Board of Directors shall prepare a certificate, to be signed by
      an authorized officer of the Company, setting forth in


                                      -2-
<PAGE>
      reasonable detail the basis for and method of determination of the per
      share Fair Market Value of the Preferred Stock. The Board will also
      certify to the Holder that this per share Fair Market Value will be
      applicable to all holders of the Company's Preferred Stock. Such
      certification must be made to Holder at least thirty (30) business days
      prior to the proposed effective date of the merger, consolidation, sale,
      or other triggering event as defined in 3(c)(iii) or 3(c)(iv).

      (d) Automatic Exercise. To the extent this Warrant is not previously
exercised, it shall be automatically exercised in accordance with Sections 3(b)
and 3(c) hereof (even if not surrendered) immediately before its expiration,
involuntary termination or cancellation.

4. Representations and Warranties of Holder and the Company

      (a) Representations and Warranties by Holder. The Holder represents and
warrants to the Company with respect to this purchase as follows:

            (i) The Holder has substantial experience in evaluating and
      investing in private placement transactions of securities of companies
      similar to the Company so that the Holder is capable of evaluating the
      merits and risks of its investment in the Company and has the capacity to
      protect its interests.

            (ii) Except for transfers to a Holder affiliate, the Holder is
      acquiring the Warrant and the Shares of Preferred Stock issuable upon
      exercise of the Warrant (collectively the "Securities") for investment for
      its own account and not with a view to, or for resale in connection with,
      any distribution thereof. The Holder understands that the Securities have
      not been registered under the Securities Act of 1933, as amended (the
      "Act") by reason of a specific exemption from the registration provisions
      of the Act which depends upon, among other things, the bona fide nature of
      the investment intent as expressed herein.

            (iii) The Holder acknowledges that the Securities must be held
      indefinitely unless subsequently registered under the Act or an exemption
      from such registration is available. The Holder is aware of the provisions
      of Rule 144 promulgated under the Act.

            (iv) The Holder is an "accredited investor" within the meaning of
      Regulation D promulgated under the Act.

            (v) The Holder has had an opportunity to discuss the Company's
      business, management and financial affairs with its management and an
      opportunity to review the Company's facilities. The Holder understands
      that such discussions, as well as the written information issued by the
      Company, were intended to describe the aspects of the Company's business
      -and prospects which the Company believes to be material but were not
      necessarily a thorough or exhaustive description.

      (b) Company hereby represents, and warrants to Holder that, except as set
forth in the schedule attached to this Warrant as Exhibit A (the "Disclosure
Schedule"), the statements in the following paragraphs of this Section 4(b) are
true and correct (a) as of the date hereof and (b)


                                      -3-
<PAGE>
except where any such representation and warranty relates specifically to an
earlier date, as of the date of any exercise of this Warrant.

            (i) Corporate Organization and Authority. Company (a) is a
      corporation duly organized, validly existing, and in good standing in its
      jurisdiction of incorporation, (b) has the corporate power and authority
      to own and operate its properties and to carry on its business as now
      conducted and as proposed to be conducted; and (c) is qualified as a
      foreign corporation in all jurisdictions where such qualification is
      required.

            (ii) Corporate Power. Company has all requisite legal and corporate
      power and authority to execute, issue and deliver the Warrant, to issue
      the Common Stock issuable upon exercise or conversion of the Warrant, and
      to carry out and perform its obligations under the Warrant and any related
      agreements.

            (iii) Authorization, Enforceability. All corporate action on the
      part of Company, its officers, directors and shareholders necessary for
      the authorization, execution, delivery and performance of its obligations
      under this Warrant and for the authorization, issuance and delivery of the
      Warrant and the Warrant Stock issuable upon exercise of the Warrant has
      been taken and this Warrant constitutes the legally binding and valid
      obligation of Company enforceable in accordance with its terms.

            (iv) Valid Issuance of Warrant and Preferred Stock. The Warrant has
      been validly issued and is free of restrictions on transfer other than
      restrictions on transfer set forth herein and under applicable state and
      federal securities laws. The Preferred Stock issuable upon conversion of
      this Warrant, when issued, sold and delivered in accordance with the terms
      of this Warrant for the consideration expressed herein, will be duly and
      validly issued, fully paid and nonassessable, and will be free of
      restrictions on transfer other than restrictions on transfer under this
      Warrant and under applicable state and federal securities laws. Subject to
      applicable restrictions on transfer, the issuance and delivery of the
      Warrant and the Preferred Stock issuable upon conversion of the Warrant
      are not subject to any preemptive or other similar rights or any liens or
      encumbrances except as specifically set forth in Company's Certificate of
      Incorporation or this Warrant. The offer, sale and issuance of the Warrant
      and Preferred Stock, as contemplated by this Warrant, are exempt from the
      prospectus and registration requirements of applicable United States
      federal and state security laws, and neither Company nor any authorized
      agent acting on its behalf has or will take any action hereafter that
      would cause the loss of such exemption.

            (v) No Conflict with Other Instruments. The execution, delivery, and
      performance of this Warrant will not result in any violation of, be in
      conflict with, or constitute a default under, with or without the passage
      of time or the giving of notice (a) any provision of Company's Certificate
      of Incorporation or by-laws; (b) any provision of any judgment, decree, or
      order to which Company is a party or by which it is bound or an event
      which results in the creation of any material lien, charge or encumbrance
      upon any material assets of Company; (c) any contract, obligation, or
      commitment to which Company is a party or by which it is bound; or (d) any
      statute, rule, or governmental regulation applicable to Company.


                                      -4-
<PAGE>
            (vi) Capitalization. As October 16, 2003, the authorized capital
      stock of Company consists of 80,000,000 shares of Common Stock, $.01 par
      value, of which 2,634,299 were issued and outstanding, and 28,325,000
      shares of Preferred Stock, $.01 par value, of which 23,489,913 are issued
      and outstanding. The outstanding shares have been duly authorized and
      validly issued (including, without limitation, issued in compliance with
      applicable federal and state securities laws), are fully paid and
      nonassessable and have been issued in compliance with the registration and
      prospectus delivery requirements of the Securities Act and the
      registration and qualification requirements of all applicable state
      securities laws, or in compliance with applicable exemptions therefrom.
      Company has reserved 6,410,000 shares of Common Stock for issuance upon
      conversion of outstanding options and warrants. Except as set forth in
      Section 4(b) of the Disclosure Schedule, there are no outstanding
      warrants, options, conversion privileges, preemptive rights or other
      rights or agreements to purchase or otherwise acquire or issue any equity
      securities or Convertible Securities of Company, nor has the issuance of
      any of the aforesaid rights to acquire securities of Company been
      authorized.

            (vii) Governmental Consents. No consent, approval, order or
      authorization of, or registration, qualification, designation, declaration
      or filing with, any federal, state or local governmental authority on the
      part of Company is required in connection with the offer, sale or issuance
      of the Warrant (and the Preferred Stock issuable upon conversion of the
      Shares), or the consummation of any other transaction contemplated hereby,
      except for the following: (a) the filing of a notice on Form D under the
      Act and b) the compliance with other applicable state securities laws,
      which compliance will have occurred within the appropriate time periods
      therefore. The offer, sale and issuance of the Warrant and the shares of
      Preferred Stock in conformity with the terms of this Warrant are exempt
      from the registration requirements of the Act and any applicable state
      laws.

5. Legends.

      (a) Each certificate representing the Securities shall be endorsed with
the following legend:

            THESE SECURITIES HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
            OF 1933 AND MAY NOT BE TRANSFERRED UNLESS COVERED BY AN EFFECTIVE
            REGISTRATION STATEMENT UNDER SAID ACT, A "NO ACTION" LETTER FROM THE
            SECURITIES AND EXCHANGE COMMISSION WITH RESPECT TO SUCH TRANSFER, A
            TRANSFER MEETING THE REQUIREMENTS OF RULE 144 OF THE SECURITIES AND
            EXCHANGE COMMISSION, OR (IF REASONABLY REQUIRED BY THE COMPANY) AN
            OPINION OF COUNSEL SATISFACTORY TO THE ISSUER TO THE EFFECT THAT ANY
            SUCH TRANSFER IS EXEMPT FROM SUCH REGISTRATION.


                                      -5-
<PAGE>
The Company need not enter into its stock records a transfer of Securities
unless the conditions specified in the foregoing legend are satisfied. The
Company may also instruct its transfer agent not to allow the transfer of any of
the Shares unless the conditions specified in the foregoing legend are
satisfied.

      (b) Removal of Legend and Transfer Restrictions. The legend relating to
the Act endorsed on a certificate pursuant to paragraph 5(a) of this Warrant
shall be removed and the Company shall issue a certificate without such legend
to the Holder of the Securities if (i) the Securities are registered under the
Act and a prospectus meeting the requirements of Section 10 of the Act is
available or (ii) the Holder provides to the Company an opinion of counsel for
the Holder reasonably satisfactory to the Company, a no-action letter or
interpretive opinion of the staff of the SEC reasonably satisfactory to the
Company, or other evidence reasonably satisfactory to the Company, to the effect
that public sale, transfer or assignment of the Securities may be made without
registration and without compliance with any restriction such as Rule 144.

6. Condition of Transfer or Exercise of Warrant. It shall be a condition to any
transfer or exercise of this Warrant that at the time of such transfer or
exercise, the Holder shall provide the Company with a representation in writing
that the Holder or transferee is acquiring this Warrant and the shares of
Preferred Stock to be issued upon exercise for investment purposes only and not
with a view to any sale or distribution, or will provide the Company with a
statement of pertinent facts covering any proposed distribution. As a further
condition to any transfer of this Warrant or any or all of the shares of
Preferred Stock issuable upon exercise of this Warrant, other than a transfer
registered under the Act, the Company may request a legal opinion, in form and
substance satisfactory to the Company and its counsel, reciting the pertinent
circumstances surrounding the proposed transfer and stating that such transfer
is exempt from the registration and prospectus delivery requirements of the Act.
The Company shall not require Holder to provide an opinion of counsel if the
transfer is to an affiliate of Holder. Each certificate evidencing the shares
issued upon exercise of the Warrant or upon any transfer of the shares (other
than a transfer registered under the Act or any subsequent transfer of shares so
registered) shall, at the Company's option, if the Shares are not freely
saleable under Rule 144(k) under the Act, contain a legend in form and substance
satisfactory to the Company and its counsel, restricting the transfer of the
shares to sales or other dispositions exempt from the requirements of the Act.
As further condition to each transfer, at the request of the Company, the Holder
shall surrender this Warrant to the Company and the transferee shall receive and
accept a Warrant, of like tenor and date, executed by the Company.

7. Adjustment for Certain Events. The number and kind of securities purchasable
upon the exercise of this Warrant and the Warrant Price shall be subject to
adjustment from time to time upon the occurrence of certain events, as follows:

      (a) Reclassification or Merger. In case of any reclassification or change
of securities of the class issuable upon exercise of this Warrant (other than a
change in par value, or from par value to no par value, or from no par value to
par value, or as a result of a subdivision or combination), or in case of any
merger of the Company with or into another corporation (other than a merger with
another corporation in which the Company is the acquiring and the surviving
corporation and which does not result in any reclassification or change of
outstanding securities issuable upon exercise of this Warrant), or in case of
any sale of all or substantially all of the


                                      -6-
<PAGE>
assets of the Company, the Company, or such successor or purchasing corporation,
as the case may be, shall duly execute and deliver to the Holder a new Warrant
(in form and substance satisfactory to the Holder of this Warrant), or the
Company shall make appropriate provision without the issuance of a new Warrant,
so that the Holder shall have the right to receive, at a total purchase price
not to exceed that payable upon the exercise of the unexercised portion of this
Warrant, and in lieu of the shares of Preferred Stock theretofore issuable upon
exercise of this Warrant, the kind and amount of shares of stock, other
securities, money and property receivable upon such reclassification, change,
merger or sale by a Holder of the number of shares of Preferred Stock then
purchasable under this Warrant, or in the case of such a merger or sale in which
the consideration paid consists all or in part of assets other than securities
of the successor or purchasing corporation, at the option of the Holder, the
securities of the successor or purchasing corporation having a value at the time
of the transaction equivalent to the value of the Preferred Stock purchasable
upon exercise of this Warrant at the time of the transaction. Any new Warrant
shall provide for adjustments that shall be as nearly equivalent as may be
practicable to the adjustments provided for in this Section 7. The provisions of
this subparagraph (a) shall similarly apply to successive reclassifications,
changes, mergers and transfers.

      (b) Subdivision or Combination of Shares. If the Company at any time while
this Warrant remains outstanding and unexpired shall subdivide or combine its
outstanding shares of Preferred Stock, the Warrant Price shall be
proportionately decreased and the number of Shares issuable; hereunder shall be
proportionately increased in the case of a subdivision and the Warrant Price
shall be proportionately increased and the number of Shares issuable hereunder
shall be proportionately decreased in the case of a combination.

      (c) Stock Dividends and Other Distributions. If the Company at any time
while this Warrant is outstanding and unexpired shall (i) pay a dividend with
respect to Preferred Stock payable in Preferred Stock, then the Warrant Price
shall be adjusted, from and after the date of determination of shareholders
entitled to receive such dividend or distribution, to that price determined by
multiplying the Warrant Price in effect immediately prior to such date of
determination by a fraction (A) the numerator of which shall be the total number
of shares of Preferred Stock outstanding immediately prior to such dividend or
distribution, and (B) the denominator of which shall be the total number of
shares of Preferred Stock outstanding immediately after such dividend or
distribution; or (ii) make any other distribution with respect to Preferred
Stock (except any distribution specifically provided for in Sections 7(a) and
7(b)), then, in each such case, provision shall be made by the Company such that
the Holder of this Warrant shall receive upon exercise of this Warrant a
proportionate share of any such dividend or distribution as though it were the
Holder of the Preferred Stock (or Common Stock issuable upon conversion thereof)
as of the record date fixed for the determination of the shareholders of the
Company entitled to receive such dividend or distribution.

      (d) Adjustment of Number of Shares. Upon each adjustment in the Warrant
Price, the number of Shares purchasable hereunder shall be adjusted, to the
nearest whole share, to the product obtained by multiplying the number of Shares
purchasable immediately prior to such adjustment in the Warrant Price by a
fraction, the numerator of which shall be the Warrant Price immediately prior to
such adjustment and the denominator of which shall be the Warrant Price
immediately thereafter.


                                      -7-
<PAGE>
8. Notice of Adjustments. Whenever any Warrant Price or the kind or number of
securities issuable under this Warrant shall be adjusted pursuant to Section 7
hereof, the Company shall prepare a certificate signed by an officer of the
Company setting forth, in reasonable detail, the event requiring the adjustment,
the amount of the adjustment, the method by which such adjustment was
calculated, and the Warrant Price and number or kind of shares issuable upon
exercise; of the Warrant after giving effect to such adjustment, and shall cause
copies of such certificate to be mailed (by certified or registered mail, return
receipt required, postage prepaid) within thirty (30) days of such adjustment to
the Holder of this Warrant as set forth in Section 18 hereof.

9. Transferability of Warrant. This Warrant is transferable on the books of the
Company at its principal office by the registered Holder hereof upon surrender
of this Warrant properly endorsed, subject to compliance with Section 6 and
applicable federal and state securities laws. The Company shall issue and
deliver to the transferee a new Warrant representing the Warrant so transferred.
Upon any partial transfer, the Company will issue and deliver to Holder a new
Warrant with respect to the Warrant not so transferred. Holder shall not have
any right to transfer any portion of this Warrant to any direct competitor of
the Company.

10. Registration Rights. The Company grants registration rights to the Holder of
this Warrant for any Common Stock of the Company obtained upon conversion of the
Preferred Stock in parity to the registration rights granted to other holders of
the Preferred Stock and agrees that the Holder of this Warrant shall be added as
a party to that certain Fourth Amended and Restated Registration Rights
Agreement dated as of September 30, 2003 of the Company (the "Registration
Rights Agreement"), and that the Shares shall be made "Registrable Securities"
under the Registration Rights Agreement.

11. No Fractional Shares. No fractional share of Preferred Stock will be issued
in connection with any exercise hereunder, but in lieu of such fractional share
the Company shall make a cash payment therefor upon the basis of the Warrant
Price then in effect.

12. Charges, Taxes and Expenses. Issuance of certificates for shares of
Preferred Stock upon the exercise of this Warrant shall be made without charge
to the Holder for any United States or state of the United States documentary
stamp tax or other incidental expense with respect to the issuance of such
certificate, all of which taxes and expenses shall be paid by the Company, and
such certificates shall be issued in the name of the Holder.

13. No Shareholder Rights Until Exercise. This Warrant does not entitle the
Holder hereof to any voting rights or other rights as a shareholder of the
Company prior to the exercise hereof.

14. Registry of Warrant. The Company shall maintain a registry showing the name
and address of the registered Holder of this Warrant. This Warrant may be
surrendered for exchange or exercise, in accordance with its terms, at such
office or agency of the Company, and the Company and Holder shall be entitled to
rely in all respects, prior to written notice to the contrary, upon such
registry.

15. Loss Theft Destruction or Mutilation of Warrant. Upon receipt by the Company
of evidence reasonably satisfactory to it of the loss, theft, destruction or
mutilation of this Warrant,


                                      -8-
<PAGE>
and, in the case of loss, theft, or destruction, of indemnity reasonably
satisfactory to it, and, if mutilated, upon surrender and cancellation of this
Warrant, the Company will execute and deliver a new Warrant, having terms and
conditions substantially identical to this Warrant, in lieu hereof.

16. Miscellaneous.

      (a) Issue Date. The provisions of this Warrant shall be construed and
shall be given effect in all respect as if it had been issued and delivered by
the Company on the date hereof.

      (b) Successors. This Warrant shall be binding upon any successors or
assigns of the Company.

      (c) Governing Law. This Warrant shall be governed by and construed in
accordance with the laws of the State of Connecticut.

      (d) Headings. The headings used in this Warrant are used for convenience
only and are not to be considered in construing or interpreting this Warrant.

      (e) Saturdays, Sundays, Holidays. If the last or appointed day for the
taking of any action or the expiration of any right required or granted herein
shall be a Saturday or a Sunday or shall be a legal holiday in the State of
Connecticut, then such action may be taken or such right may be exercised on the
next succeeding day not a legal holiday.

      (f) Waiver of July Trial. Each of the parties hereto hereby waives to the
fullest extent permitted by applicable law, any right it may have to a trial by
jury in respect of any litigation directly or indirectly arising out of, under
or in connection with this Warrant or the Preferred Shares.

      (g) Attorney's Fees. In the event of any dispute between the parties
concerning the terms and provisions of this Warrant, the party prevailing in
such dispute shall be entitled to collect from the other party all costs
incurred in such dispute, including reasonable attorney's fees.

17. No Impairment. The Company will not, by amendment of its Certificate; of
Incorporation or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms of this Warrant, but will at all
times in good faith assist in the carrying out of all such terms and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the Holder hereof against impairment.

18. Addresses. Any notice required or permitted hereunder shall be in writing
and shall be mailed by overnight courier, registered or certified mail, return
receipt required, and postage prepaid, or otherwise delivered by hand or by
messenger, addressed as set forth below, or at such other address as the Company
or the Holder hereof shall have furnished to the other party.

                  If to the Company: Viacell, Inc.
                                     131 Clarendon St.


                                      -9-
<PAGE>
                                     Boston, MA 02116
                                     Attn: Dean Rapaport

                  If to the Holder:  General Electric Capital Corporation
                                     401 Merritt 7, Suite 23
                                     Norwalk, CT 06851-1177
                                     Attn:  Credit Manager-Life Science and
                                     Technology Finance


IN WITNESS WHEREOF, Viacell, Inc. has caused this Warrant to be executed by
its officers thereunto duly authorized.

Dated as of Oct. 16, 2003           By: /s/ Jeffrey A. Sacher
                                        --------------------------------
                                    Name: Jeffrey A. Sacher
                                          ------------------------------
                                    Title: CFO
                                           -----------------------------


                                      -10-
<PAGE>
NOTICE OF EXERCISE

TO:

1. The undersigned Warrantholder ("Holder") elects to acquire shares of the
Series Preferred Stock (the "Preferred Stock") of            , (the "Company"),
pursuant to the terms of the Stock Purchase Warrant dated ______________, 200_,
(the "Warrant").

2. The Holder exercises its rights under the Warrant as set forth below:

            ( )   The Holder elects to purchase     shares of Preferred Stock as
                  provided in Section 3(a) and tenders herewith a check in the
                  amount of $__________as payment of the purchase price.

            ( )   The Holder elects to convert the purchase rights into shares
                  of Preferred Stock as provided in Section 3(b) of the Warrant.

3. The Holder surrenders the Warrant with this Notice of Exercise.

The Holder represents that it is acquiring the aforesaid shares of Preferred
Stock for investment and not with a view to or for resale in connection with
distribution and that the Holder has no present intention of distributing or
reselling the shares.

Please issue a certificate representing the shares of the Preferred Stock in the
name of the Holder or in such other name as is specified below:

            Name:
            Address:


            Taxpayer I.D.:
                                    ------------------------------------
                                    (Holder)

                                    By:
                                       ---------------------------------

                                    Title:
                                          ------------------------------

                                    Date:
                                          ------------------------------