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                                                                    EXHIBIT 10.2

                           WARRANT PURCHASE AGREEMENT

      This Warrant Purchase Agreement (the "Agreement") is made as of August 29,
2005 by and between ViaCell, Inc., a Delaware corporation (the "Company"), and
Amgen Inc., a Delaware corporation ("Purchaser").

      The Company and Purchaser hereby confirm their respective agreements as
follows:

      1.    AUTHORIZATION AND PURCHASE OF THE WARRANT.

            1.1 Authorization of the Warrant. The Company's Board of Directors
has authorized the issuance by the Company and the sale to the Purchaser of a
warrant (the "Warrant") to purchase an aggregate of up to Two Hundred Thousand
(200,000) fully paid and nonassessable shares of Common Stock, par value $0.01
per share (the "Common Stock"), of the Company, all as more fully described, and
subject to the conditions set forth, below and in the form of Warrant annexed
hereto as Exhibit 1.1. The shares of Common Stock issuable upon exercise of the
Warrant are herein referred to as the "Warrant Shares"; and the Warrant and the
Warrant Shares are sometimes herein together referred to as the "Securities."

            1.2 Purchase of Warrant. Subject to the terms and conditions set
forth below and in the Warrant, the Company agrees to issue to Purchaser, and
Purchaser hereby agrees to purchase from the Company, the Warrant in
consideration for the rights granted to the Company under that certain Amendment
No.1 to the Collaboration Agreement (the "Amendment") by and between the Company
and Purchaser. A copy of the Amendment, in the form to be executed and delivered
by each of the Purchaser and the Company on the Closing Date (as defined below),
is annexed hereto as Exhibit 1.2.

      2.    THE CLOSING.

            Closing Date. The closing of the purchase and sale of the Warrant to
Purchaser hereunder (the "Closing") shall be held at the offices of the Company,
at 5:00 p.m. EST, on August 29, 2005, or at such other time and place as the
Company and Purchaser mutually agree upon, orally or in writing (the "Closing
Date"). On the Closing Date, the Company shall deliver to Purchaser the Warrant
registered in the name of Purchaser.

      3.    CONDITIONS OF THE PURCHASER'S OBLIGATIONS AT CLOSING.

            The obligations of Purchaser to the Company under this Agreement are
subject to the fulfillment, on or before the Closing, of each of the following
conditions, unless otherwise waived by Purchaser:

            3.1 Representations and Warranties. The representations and
warranties of the Company contained in Section 5 shall be true and correct on
and as of the Closing with the same effect as though such representations and
warranties had been made on and as of the date of the Closing (except for
representations and warranties that speak as of a specific date, which need only
be true and correct as of such date).

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            3.2 Performance. The Company shall have performed and complied with
all covenants, agreements, obligations and conditions contained in this
Agreement that are required to be performed or complied with by it on or before
the Closing.

            3.3 Qualifications. All authorizations, approvals or permits, if
any, of any governmental authority or regulatory body of the United States or of
any state that are required to be in effect as of the Closing in connection with
the lawful issuance and sale of the Warrant pursuant to this Agreement shall be
obtained and effective as of the Closing.

            3.4 Consents and Waivers. The Company shall have obtained any and
all consents and waivers necessary or appropriate for consummation of the
transactions contemplated by this Agreement, including but not limited to the
waiver of any rights of participation held by any other shareholder of the
Company.

            3.5 Compliance Certificate. The President of the Company shall
deliver to Purchaser at the Closing a certificate certifying that the conditions
specified in Sections 3.1, 3.2, 3.3 and 3.4 have been fulfilled.

            3.6 Secretary's Certificate. The Secretary of the Company shall
deliver to Purchaser at the Closing a certificate certifying as to (i) the
incumbency of the Company's principal officers, and (ii) a copy of the
resolutions of the Board of Directors of the Company, authorizing and approving
all matters in connection with this Agreement and the Agreements (as defined
herein) and the transactions contemplated hereby and thereby.

            3.7 Opinion of Company Counsel. Purchaser shall have received from
Ropes & Gray LLP, counsel for the Company, an opinion, dated as of the Closing,
in substantially the form of Exhibit 3.7.

            3.8 Amendment. The Company shall have executed and delivered the
Amendment and such agreement shall be in full force and effect.

            3.9 Proceedings and Documents. All corporate and other proceedings
in connection with the transactions contemplated at the Closing hereby and all
documents and instruments incident to such transactions shall be satisfactory in
substance and form to the Purchaser, and the Purchaser shall have received all
such counterpart originals or certified or other copies of such documents as it
may reasonably request.

      4.    CONDITIONS OF THE COMPANY'S OBLIGATIONS AT CLOSING.

            The obligations of the Company to Purchaser under this Agreement are
subject to the fulfillment, on or before the Closing, of each of the following
conditions, unless otherwise waived by Company:

            4.1 Representations and Warranties. The representations and
warranties of Purchaser contained in Section 6 shall be true and correct on and
as of the Closing with the same effect as though such representations and
warranties had been made on and as of the Closing (except for representations
and warranties that speak as of a specific date, which need only be true and
correct as of such date).

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            4.2 Performance. All covenants, agreements and conditions contained
in this Agreement to be performed by Purchaser on or prior to the Closing shall
have been performed or complied with in all material respects.

            4.3 Qualifications. All authorizations, approvals or permits, if
any, of any governmental authority or regulatory body of the United States or of
any state that are required to be in effect as of the Closing in connection with
the lawful issuance and sale of the Warrant pursuant to this Agreement shall be
obtained and effective as of the Closing.

            4.4 Amendment. The Purchaser shall have executed the Amendment and
such agreement shall be in full force and effect.

      5.    REPRESENTATIONS AND WARRANTIES OF THE COMPANY.

            The Company represents and warrants to Purchaser that, except as set
forth on a Schedule of Exceptions attached hereto as Exhibit 5 (which schedule
shall specifically identify the relevant subsection hereof modified thereby and
the contents of which shall be deemed to be representations and warranties as if
made hereunder):

            5.1 Organization. The Company is duly organized and validly existing
in good standing under the laws of the jurisdiction of its organization. Each of
the Company and its Subsidiaries (as defined in Rule 405 under the Securities
Act of 1933, as amended (the "Securities Act")) has full power and authority to
own, operate and occupy its properties and to conduct its business as presently
conducted and as described in the SEC Documents (hereinafter defined) and is
registered or qualified to do business and in good standing in each jurisdiction
in which it owns or leases property or transacts business except where the
failure to be so qualified would not have a material adverse effect upon the
business, financial condition, properties or operations of the Company and its
Subsidiaries, considered as one enterprise.

            5.2 Due Authorization; Consents. The Company has all requisite
corporate power and has taken all requisite corporate action to execute and
deliver each of this Agreement and the Warrant (collectively, the "Agreements"),
to sell and issue the Securities and to carry out and perform all of its
obligations hereunder and thereunder. Each of the Agreements has been duly
authorized, executed and delivered on behalf of the Company and constitutes the
valid and binding agreement of the Company, enforceable in accordance with its
terms, except as limited by applicable bankruptcy, insolvency, reorganization,
moratorium, fraudulent conveyance, and any other laws of general application
affecting enforcement of creditors' rights generally, and as limited by laws
relating to the availability of a specific performance, injunctive relief, or
other equitable remedies. All consents, approvals and authorizations of, and
registrations, qualifications and filings with, any federal or state
governmental agency, authority or body, or any third party, required in
connection with the execution, delivery and performance of this Agreement and
the consummation of the transactions contemplated hereby have been obtained and
are effective as of the Closing.

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            5.3 Validity of Securities. The Warrant, when sold against the
consideration therefor as provided herein, will be validly authorized and
issued, fully paid and nonassessable. The issuance and delivery of the Warrant
is not subject to preemptive or any similar rights of the stockholders of the
Company or any liens or encumbrances arising through the Company; and when the
Warrant Shares are issued upon exercise and in accordance with the terms of the
Warrant, they will be validly issued and outstanding, fully paid and
nonassessable and free of any liens or encumbrances arising through the Company.

            5.4 SEC Documents; Financial Statements. Each of the Company's
Annual Report on Form 10-K for the fiscal year ended December 31, 2004, the
Company's Notice of Annual Meeting of Stockholders and Proxy Statement dated
April 29, 2005, and the Company's Quarterly Report on Form 10-Q for the quarter
ended March 31, 2005, and all other documents, if any, filed or furnished by the
Company since January 20, 2005 pursuant to the reporting requirements of the
Securities Exchange Act of 1934, as amended (the "Exchange Act;" collectively,
the above documents shall be referred to hereinafter as the "SEC Documents"), as
filed by the Company with the Securities and Exchange Commission (the "SEC") or
incorporated by reference therein conforms in all material respects to the
requirements of the Exchange Act, as applicable, and the rules, regulations and
instructions of the SEC thereunder. Each of the SEC Documents, as of its
respective date, contains no untrue statement of a material fact or omits to
state a material fact required to be stated therein or necessary to make the
statements made therein, in the light of the circumstances in which they were
made, not misleading. The financial statements of the Company included in the
SEC Documents (the "Financial Statements") comply as to form in all material
respects with applicable accounting requirements and with the published rules
and regulations of the SEC with respect thereto. Except as may be indicated in
the notes to the Financial Statements, the Financial Statements have been
prepared in accordance with generally accepted accounting principles
consistently applied and fairly present the consolidated financial position and
operating results of the Company and its subsidiaries as of the dates, and for
the periods, indicated therein.

            5.5 Non-Contravention. The execution and delivery of the Agreement,
the issuance and sale of the Securities to be sold by the Company under this
Agreement, the fulfillment of the terms of the Agreements and the consummation
of the transactions contemplated hereby will not (A) conflict with or constitute
a violation of, or default (with the passage of time or otherwise) under, (i)
any material bond, debenture, note or other evidence of indebtedness, or under
any material lease, contract, indenture, mortgage, deed of trust, loan
agreement, joint venture or other agreement or instrument to which the Company
or any Subsidiary is a party or by which it or any of its Subsidiaries or their
respective properties are bound, (ii) the charter, by-laws or other
organizational documents of the Company or any Subsidiary, or (iii) any law,
administrative regulation applicable to the Company or any Subsidiary or any
ordinance or order of any court or governmental agency, arbitration panel or
authority applicable to and specifically naming the Company or any Subsidiary or
their respective properties, or (B) result in the creation or imposition of any
lien, encumbrance, claim, security interest or restriction whatsoever upon any
of the material properties or assets of the Company or any Subsidiary or an
acceleration of indebtedness pursuant to any obligation, agreement or condition
contained in any material bond, debenture, note or any other evidence of
indebtedness or any material indenture, mortgage, deed of trust or any other
agreement or instrument to which the Company or any Subsidiary is a party or by
which any of them is bound

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<PAGE>

or to which any of the property or assets of the Company or any Subsidiary is
subject. No consent, approval, authorization or other order of, or registration,
qualification or filing with, any regulatory body, administrative agency, or
other governmental body in the United States is required for the execution and
delivery of the Agreements and the valid issuance and sale of the Securities to
be sold pursuant to this Agreement, other than such as have been made or
obtained, and except for any securities filings required to be made under
federal or state securities laws.

            5.6 Liabilities. Except as set forth in the SEC Documents, the
Company has no material indebtedness for borrowed money that the Company has
directly or indirectly created, incurred, assumed, or guaranteed, or with
respect to which the Company has otherwise become directly or indirectly liable.

            5.7 Capitalization. The capitalization of the Company as of August
29, 2005 is as set forth in the SEC Documents (excluding unvested options and
treasury shares). The Company has not issued any capital stock since that date
other than pursuant to (i) employee benefit plans disclosed in the SEC
Documents, or (ii) outstanding warrants or options disclosed in the SEC
Documents. The outstanding shares of capital stock of the Company have been duly
and validly issued and are fully paid and nonassessable, have been issued in
compliance with all federal and state securities laws, and were not issued in
violation of any preemptive rights or similar rights to subscribe for or
purchase securities. Except as set forth in or contemplated by the SEC
Documents, there are no outstanding rights (including, without limitation,
preemptive rights), warrants or options to acquire, or instruments convertible
into or exchangeable for, any unissued shares of capital stock or other equity
interest in the Company or any Subsidiary, or any contract, commitment,
agreement, understanding or arrangement of any kind to which the Company is a
party or of which the Company has knowledge and relating to the issuance or sale
of any capital stock of the Company or any Subsidiary, any such convertible or
exchangeable securities or any such rights, warrants or options. Without
limiting the foregoing, no preemptive right, co-sale right, right of first
refusal, registration right, or other similar right exists with respect to the
Warrant or the issuance and sale thereof. No further approval or authorization
of any stockholder, the Board of Directors of the Company or others is required
for the issuance and sale of the Warrant or the Warrant Shares upon the exercise
of the Warrant. The Company owns the entire equity interest in each of its
Subsidiaries, free and clear of any pledge, lien, security interest,
encumbrance, claim or equitable interest, other than as described in the SEC
Documents. Except as disclosed in the SEC Documents, there are no stockholders
agreements, voting agreements or other similar agreements with respect to the
Common Stock to which the Company is a party or, to the knowledge of the
Company, between or among any of the Company's stockholders.

            5.8 Legal Proceedings. There is no legal or governmental proceeding
pending or, to the knowledge of the Company, threatened to which the Company or
any Subsidiary is or may be a party or of which the business or property of the
Company or any Subsidiary is subject that is required to be disclosed in the SEC
Documents and that is not disclosed in the SEC Documents.

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            5.9 No Violations. Neither the Company nor any Subsidiary is in
violation of its charter, bylaws, or other organizational document, or in
violation of any law, administrative regulation, ordinance or order of any court
or governmental agency, arbitration panel or authority applicable to the Company
or any Subsidiary, which violation, individually or in the aggregate, would be
reasonably likely to have a material adverse effect on the business or financial
condition of the Company and its Subsidiaries, considered as one enterprise, or
is in default (and there exists no condition which, with the passage of time or
otherwise, would constitute a default) in any material respect in the
performance of any bond, debenture, note or any other evidence of indebtedness
in any indenture, mortgage, deed of trust or any other material agreement or
instrument to which the Company or any Subsidiary is a party or by which the
Company or any Subsidiary is bound or by which the properties of the Company or
any Subsidiary are bound, which would be reasonably likely to have a material
adverse effect upon the business or financial condition operating results of the
Company and its Subsidiaries, considered as one enterprise.

            5.10 Governmental Permits, Etc. Each of the Company and its
Subsidiaries has all necessary franchises, licenses, certificates and other
authorizations from any foreign, federal, state or local government or
governmental agency, department, or body that are currently necessary for the
operation of the business of the Company and its Subsidiaries as currently
conducted and as described in the SEC Documents except where the failure to
currently possess could not reasonably be expected to have a material adverse
effect upon the business or financial condition operating results of the Company
and its Subsidiaries, considered as one enterprise.

            5.11 Title to Properties and Assets. Except as set forth in the SEC
Documents, the Company has good and marketable title to the properties and
assets that it owns held in each case subject to no lien of any kind except for
liens for taxes that are not yet due and payable or, in the case of leased real
property, easements and other rights or restrictions of record that do not
materially impair the use or value of such property to the Company. With respect
to the property and assets it leases, the Company is in compliance with such
leases and, to the best of the Company's knowledge, the Company holds valid
leasehold interests in such assets free of any liens, encumbrances, security
interests or claims of any party other than the lessors of such property and
assets.

            5.12 Intellectual Property. Subject to the matters discussed under
"Risk Factors" in the SEC Documents (i) each of the Company and its Subsidiaries
owns or possesses sufficient rights to use all patents, patent rights,
trademarks, copyrights, licenses, inventions, trade secrets, trade names and
know-how (collectively, "Intellectual Property") described or referred to in the
SEC Documents as owned by it or that are necessary for the conduct of its
business as now conducted or as proposed to be conducted as described in the SEC
Documents except where the failure to currently own or possess would not have a
material adverse effect on the condition (financial or otherwise), earnings,
operations, business or business prospects of the Company and its Subsidiaries
considered as one enterprise, (ii) neither the Company nor any of its
Subsidiaries has received any notice of, or has any knowledge of, any
infringement of asserted rights of a third party with respect to any
Intellectual Property that, individually or in the aggregate, would have a
material adverse effect on the financial condition or business of the Company
and its Subsidiaries considered as one enterprise and (iii) neither the Company
nor any of its Subsidiaries has received any notice of any infringement of
rights of a third party with

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respect to any Intellectual Property that, individually or in the aggregate,
would have a material adverse effect upon the business, operating results or
financial condition, operating results of the Company and its Subsidiaries,
considered as one enterprise.

            5.13 No Infringement. Except as disclosed in the SEC Documents, to
the best of the Company's knowledge, the Company has not violated or infringed,
and is not currently violating or infringing, and the Company has not received
any communications alleging that the Company (or any of its employees or
consultants) has violated or infringed or, by conducting its business as
proposed, would violate or infringe, any Intellectual Property of any other
person or entity.

            5.14 Environmental Matters. During the period that the Company has
owned or leased its properties and facilities, (a) there have been no disposals,
releases or threatened releases of Hazardous Materials (as defined below) on,
from or under such properties or facilities, (b) neither the Company nor, to the
Company's knowledge, any third party, has used, generated, manufactured or
stored on, under or about such properties or facilities or transported to or
from such properties or facilities any Hazardous Materials. The Company has no
knowledge of any presence, disposals, releases or threatened releases of
Hazardous Materials on, from or under any of such properties or facilities,
which may have occurred prior to the Company having taken possession of any of
such properties or facilities. For purposes of this Agreement, the terms
"disposal", "release", and "threatened release" shall have the definitions
assigned thereto by the Comprehensive Environmental Response, Compensation and
Liability Act of 1980, 42 U.S.C. Section 9601 et seq., as amended ("CERCLA").
For the purposes of this Section, "Hazardous Materials" shall mean any hazardous
or toxic substance, material or waste which is regulated under, or defined as a
"hazardous substance", "pollutant", "contaminant", "toxic chemical", "hazardous
material", "toxic substance", or "hazardous chemical" under (1) CERCLA; (2) the
Emergency Planning and Community Right-to-Know Act, 42 U.S.C. Section 11001 et
seq.; (3) the Hazardous Materials Transportation Act, 49 U.S.C. Section 1801, et
seq.; (4) the Toxic Substances Control Act, 15 U.S.C. Section 2601 et seq.; (5)
the Occupational Safety and Health Act of 1970, 29 U.S.C. Section 651 et seq.;
(6) regulations promulgated under any of the above statutes; or (7) any
applicable state or local statute, ordinance, rule, or regulation that has a
scope or purpose similar to those statutes identified above.

            5.15 No Material Adverse Change. Except as disclosed in the SEC
Documents, since January 20, 2005, there has not been (i) any material adverse
change in the financial condition or operating results of the Company and its
Subsidiaries considered as one enterprise nor has any material adverse event
occurred to the Company or its Subsidiaries, (ii) any material adverse event
affecting the Company, (iii) any obligation, direct or contingent, that is
material to the Company and its Subsidiaries considered as one enterprise,
incurred by the Company or any Subsidiary, except obligations incurred in the
ordinary course of business, (iv) any dividend or distribution of any kind
declared, paid or made on the capital stock of the Company or any of its
Subsidiaries, or (v) any loss or damage (whether or not insured) to the physical
property of the Company or any of its Subsidiaries which has been sustained
which has a material adverse effect on the condition (financial or otherwise),
operating results, operations, business or business prospects of the Company and
its Subsidiaries considered as one enterprise.

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            5.16 Disclosure. No representation or warranty by the Company in
this Agreement or in any statement or certificate signed by any officer of the
Company furnished or to be furnished to the Purchaser pursuant to this Agreement
contains or will contain any untrue statement of a material fact or omits or
will omit to state any material fact required to be stated therein or necessary
in order to make the statements therein, in light of the circumstances in which
they are made, not misleading.

            5.17 NASDAQ Compliance. The Company's Common Stock is registered
pursuant to Section 12(g) of the Exchange Act and is listed on The Nasdaq Stock
Market, Inc. National Market (the "Nasdaq National Market"), and the Company has
taken no action designed to, or likely to have the effect of, terminating the
registration of the Common Stock under the Exchange Act or de-listing the Common
Stock from the Nasdaq National Market, nor has the Company received any
notification that the SEC or the National Association of Securities Dealers,
Inc. ("NASD") is contemplating terminating such registration or listing.

            5.18 Listing. The Company shall comply with all requirements of the
National Association of Securities Dealers, Inc. with respect to the issuance of
the Warrant Shares and the listing thereof on the Nasdaq National Market.

            5.19 No Manipulation of Stock. The Company has not taken and will
not, in violation of applicable law, take, any action designed to or that might
reasonably be expected to cause or result in stabilization or manipulation of
the price of the Common Stock to facilitate the sale or resale of the
Securities.

            5.20 Confidential Information and Invention Assignment Agreements.
Each employee, consultant and officer of the Company and each Subsidiary has
executed an agreement with the Company or a Subsidiary, as applicable, regarding
confidentiality and proprietary information. The Company is not aware that any
of its or any Subsidiary's employees or consultants is in violation thereof, and
the Company will use its best efforts to prevent any such violation.

      6.    REPRESENTATIONS AND WARRANTIES OF PURCHASER.

            Purchaser hereby represents and warrants to the Company as follows:

            6.1 Investment Experience. Purchaser is, and at the time it
exercises the Warrant issued to it will be, an accredited investor within the
meaning of Rule 501 under the Securities Act of 1933, as amended (the
"Securities Act"). Purchaser is aware of the Company's business affairs and
financial condition and has acquired sufficient information about the Company to
reach an informed and knowledgeable decision to acquire the Securities.
Purchaser has such business and financial experience as is required to give it
the capacity to protect its own interests in connection with the purchase of the
Securities. Purchaser has had the opportunity to ask questions and receive
answers concerning the terms and conditions of its purchase of the Securities
and to obtain any additional information from the Company that is necessary.
Purchaser believes it has received all the information it considers necessary or
appropriate for deciding whether to purchase the Securities.

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            6.2 Investment Intent. This Agreement is made with Purchaser in
reliance upon Purchaser's representation to the Company, which by Purchaser's
execution of this Agreement it hereby confirms that it is purchasing the
Securities for investment for its own account, not as a nominee or agent, only
and not with a view to, or for resale in connection with, any "distribution"
thereof within the meaning of the Securities Act and Purchaser has no present
intention of selling, granting any participation in or otherwise distributing
the same. Purchaser understands that the Securities have not been registered
under the Securities Act or registered or qualified under any state securities
law in reliance on specific exemptions therefrom, which exemptions may depend
upon, among other things, the bona fide nature of Purchaser's investment intent
as expressed herein. By executing this Agreement, Purchaser further represents
that, as of the date hereof, it does not have any contract, undertaking,
agreement or arrangement with any person to sell, transfer or grant
participations to such person or to any third person, with respect to any of the
Securities.

            6.3 Authorization. The Purchaser has full power and authority to
enter into this Agreement. The Agreements, when executed and delivered by the
Purchaser, will constitute valid and legally binding obligations of the
Purchaser, enforceable in accordance with their terms, except as limited by
applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent
conveyance, and any other laws of general application affecting enforcement of
creditors' rights generally, and as limited by laws relating to the availability
of a specific performance, injunctive relief, or other equitable remedies.

            6.4 No Legal, Tax or Investment Advice. Purchaser understands that
nothing in the Agreements or any other materials presented to Purchaser in
connection with the purchase and sale of the Securities constitutes legal, tax
or investment advice. Purchaser has consulted such legal, tax and investment
advisors as it, in its sole discretion, has deemed necessary or appropriate in
connection with its purchase of the Securities.

            6.5 Restricted Securities. The Purchaser understands that the
Securities are "restricted securities" under applicable U.S. federal and state
securities laws and that, pursuant to these laws, the Purchaser must hold the
Securities indefinitely unless they are registered with the Securities and
Exchange Commission and qualified by state authorities, or an exemption from
such registration and qualification requirements is available. The Purchaser
acknowledges that the Company has no obligation to register or qualify the
Securities for resale except as set forth in the Agreement. The Purchaser
further acknowledges that if an exemption from registration or qualification is
available, it may be conditioned on various requirements including, but not
limited to, the time and manner of sale, the holding period for the Securities,
and on requirements relating to the Company which are outside of the Purchaser's
control, and which the Company is under no obligation and may not be able to
satisfy.

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      7.    RESTRICTIONS ON TRANSFER OF SECURITIES; REGISTRATION OF THE WARRANT
            SHARES; COMPLIANCE WITH THE SECURITIES ACT.

            7.1 Restrictions on Transferability Prior to Registration. The
Securities shall not be offered, resold, pledged or otherwise transferred from
Purchaser to a transferee other than in accordance with (i) the provisions of
this Section 7 and (ii) in a transaction meeting the requirements of Rule 144
under the Securities Act ("Rule 144") or otherwise in accordance with the
Securities Act and the applicable securities laws of any state of the United
States or any other applicable jurisdiction. Purchaser will be required to
notify any subsequent purchaser of any then existing resale restrictions as set
forth above and to comply with the provisions of this Section 7.

            7.2 Restrictive Legends. Until the earlier of the first anniversary
of the Closing Date or such time as the Registration Statement referred to in
Section 7.4 becomes effective or the Securities have been sold pursuant to a
registration statement or an exemption from the registration requirements of the
Securities Act, each certificate representing any of the Securities (or any
other securities issued in respect of the Securities upon any stock split or
stock dividend) shall (unless otherwise permitted by the provisions hereof) be
stamped or otherwise imprinted with a legend substantially in the following form
(in addition to any legend required under applicable federal or state securities
laws). Such legend shall be removed by delivery of substitute certificates
without legend if such legend is not required for purposes of the Securities Act
or this Agreement.

      THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR
      INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933.
      THE SECURITIES MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH
      REGISTRATION OR AN EXEMPTION THEREFROM. THE SECURITIES REPRESENTED BY THIS
      CERTIFICATE AND THE RIGHTS OF THE HOLDER HEREOF ARE SUBJECT TO CERTAIN
      RESTRICTIONS ON TRANSFER AND OTHER RESTRICTIONS, AND THE HOLDER OF THE
      SECURITIES REPRESENTED BY THIS CERTIFICATE (INCLUDING ANY FUTURE HOLDER)
      IS BOUND BY THE TERMS OF A WARRANT PURCHASE AGREEMENT BETWEEN THE ORIGINAL
      PURCHASER AND THE COMPANY (COPIES OF WHICH MAY BE OBTAINED FROM THE
      COMPANY).

            7.3 Any Subsequent Holder of the Warrant to Expressly Assume
Obligations Hereunder; Purchaser's Ability to Transfer. Purchaser hereby
covenants and agrees that from and after the date hereof, Purchaser may transfer
(as defined in the Warrant) the Warrant only in accordance with the provisions
of this Section 7 and only to a transferee (referred to herein as a "Holder" of
the Warrant) who expressly and in writing agrees with Purchaser and the Company,
at the time of such transfer, to assume all of the obligations of, and comply
with all of the provisions applicable to, Purchaser under this Agreement and
Holder under the Warrant.

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            7.4 Registration Procedures and Expenses.

                  (a) The Company shall:

                  (i) use its reasonable efforts to prepare and file with the
            SEC, within 30 days after the first exercise of the Warrant, a
            registration statement (the "Registration Statement") to enable the
            resale of the Warrant Shares by Purchaser from time to time through
            the automated quotation system of the Nasdaq National Market or in
            privately-negotiated transactions; provided that, the Company may
            delay the filing of the Registration Statement for a period not to
            exceed 90 days if there exists at the time material non-public
            information relating to the Company which, in the reasonable opinion
            of the Company, should not be disclosed and the Company has provided
            Purchaser with prior written notice in writing of such delay;

                  (ii) use its reasonable efforts to cause the Registration
            Statement to become effective within 90 days after the Registration
            Statement is filed by the Company;

                  (iii) use its reasonable efforts to prepare and file with the
            SEC such amendments and supplements to the Registration Statement
            and the Prospectus used in connection therewith as may be necessary
            to keep the Registration Statement current and effective for a
            period not exceeding, with respect to Warrant Shares, the earlier of
            (i) the date on which Purchaser may sell all Warrant Shares then
            held by Purchaser without restriction by the volume limitations of
            Rule 144(e) of the Securities Act, or (ii) such time as all Warrant
            Shares acquired on exercise of the Warrant have been sold pursuant
            to a registration statement;

                  (iv) furnish to Purchaser with respect to the Warrant Shares
            registered under the Registration Statement such number of copies of
            the Registration Statement, Prospectuses and Preliminary
            Prospectuses in conformity with the requirements of the Securities
            Act and such other documents as Purchaser may reasonably request, in
            order to facilitate the public sale or other disposition (a
            "Disposition") of all or any of the Warrant Shares by Purchaser;

                  (v) file documents required of the Company for normal blue sky
            clearance in states specified in writing by Purchaser, provided,
            however, that the Company shall not be required to qualify to do
            business or consent to service of process in any jurisdiction in
            which it is not now so qualified or has not so consented;

                  (vi) bear all Registration Expenses in connection with the
            procedures in paragraph (a) of this Section 7.4 and the registration
            of the Warrant Shares pursuant to the Registration Statement;
            "Registration Expenses" shall mean all expenses, except for Selling
            Expenses, incurred by the Company in complying with the registration
            provisions herein described, including, without limitation, all
            registration and filing fees (including with respect to filings
            required to be made

                                       11
<PAGE>

            with the SEC); fees and expenses of compliance with securities or
            blue sky laws (including the reasonable fees and disbursements of
            counsel for the selling holders solely in connection with blue sky
            qualifications of the Warrant Shares); printing, messenger,
            telephone and delivery expenses; fees and disbursements of counsel
            for the Company and the sellers of the Warrant Shares; fees and
            disbursements of all independent certified public accountants of the
            Company; fees and expenses of other persons retained by the Company
            (including attorneys' fees); and all registration, filing and other
            fees and expenses associated with any NASD filing required to be
            made in connection with the Registration Statement. "Selling
            Expenses" shall mean all stock transfer taxes applicable to the
            Warrant Shares by reason of issuance or transfer in a name other
            than that in which the Warrant is registered, and all other expenses
            incurred by Purchaser relating to the Warrant Shares;

                  (vii) advise Purchaser, promptly after it shall receive notice
            or obtain knowledge of the issuance of any stop order by the SEC
            delaying or suspending the effectiveness of the Registration
            Statement or of the initiation or threat of any proceeding for that
            purpose; and it will promptly use its reasonable efforts to prevent
            the issuance of any stop order or to obtain its withdrawal at the
            earliest possible moment if such stop order should be issued; and

                  (viii) cause all Warrant Shares covered by the Registration
            Statement to be quoted on the NASDAQ national market or listed on
            each securities exchange on which similar securities issued by the
            Company are then listed.

                  (b) Purchaser shall furnish the Company such information
regarding Purchaser, the Warrant Shares held by Purchaser and the intended
method of disposition of such securities as shall be specifically required by
the Securities Act and the rules and regulations promulgated thereunder to
effect the registration of the Warrant Shares.

            7.5 Transfer of Warrant Shares After Registration; Suspension.

                  (a) Purchaser agrees that it will promptly notify the Company
of any material changes in the information set forth in the Registration
Statement regarding Purchaser or its plan of distribution.

                  (b) Except in the event that paragraph (c) below applies, the
Company shall (i) if deemed necessary by the Company, prepare and file from time
to time with the SEC a post-effective amendment to the Registration Statement or
a supplement to the related Prospectus or a supplement or amendment to any
document incorporated therein by reference or file any other required document
so that such Registration Statement will not contain an untrue statement of a
material fact or omit to state a material fact required to be stated therein or
necessary to make the statements therein not misleading, and so that, as
thereafter delivered to purchasers of the Warrant Shares being sold thereunder,
such Prospectus will not contain an untrue statement of a material fact or omit
to state a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading; (ii) provide Purchaser copies of any documents filed pursuant to
Section 7.5; and

                                       12
<PAGE>

(iii) inform Purchaser that the Company has complied with its obligations in
Section 7 (or that, if the Company has filed a post-effective amendment to the
Registration Statement which has not yet been declared effective, the Company
will notify Purchaser to that effect, will use its reasonable efforts to secure
the effectiveness of such post-effective amendment as promptly as possible and
will promptly notify Purchaser pursuant to Section 7.5(c) hereof when the
amendment has become effective).

                  (c) Subject to paragraph (d) below, in the event (i) of any
request by the SEC or any other federal or state governmental authority during
the period of effectiveness of the Registration Statement for amendments or
supplements to a Registration Statement or related Prospectus or for additional
information; (ii) of the issuance by the SEC or any other federal or state
governmental authority of any stop order suspending the effectiveness of a
Registration Statement or the initiation of any proceedings for that purpose;
(iii) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Warrant Shares for sale in any jurisdiction or the initiation or threatening of
any proceeding for such purpose; or (iv) of any event or circumstance which,
upon the advice of its counsel, necessitates the making of any changes in the
Registration Statement or Prospectus, or any document incorporated or deemed to
be incorporated therein by reference, so that, in the case of the Registration
Statement, it will not contain any untrue statement of a material fact or any
omission to state a material fact required to be stated therein or necessary to
make the statements therein not misleading, and that in the case of the
Prospectus, it will not contain any untrue statement of a material fact or any
omission to state a material fact required to be stated therein or necessary to
make the statements therein, in the light of the circumstances under which they
were made, not misleading; then the Company shall deliver a certificate in
writing to Purchaser (the "Suspension Notice") to the effect of the foregoing
and, upon receipt of such Suspension Notice, Purchaser will refrain from selling
any Warrant Shares pursuant to the Registration Statement (a "Suspension") until
Purchaser's receipt of copies of a supplemented or amended Prospectus prepared
and filed by the Company, or until it is advised in writing by the Company that
the current Prospectus may be used, and has received copies of any additional or
supplemental filings that are incorporated or deemed incorporated by reference
in any such Prospectus. In the event of any Suspension, the Company will use its
reasonable efforts to cause the use of the Prospectus so suspended to be resumed
as soon as reasonably practicable within 30 business days after the delivery of
a Suspension Notice to Purchaser. In addition to and without limiting any other
remedies (including, without limitation, at law or at equity) available to
Purchaser, Purchaser shall be entitled to specific performance in the event that
the Company fails to comply with the provisions of this Section 7.5(c). In
addition to the foregoing, the Company may suspend the use of the of the
Registration Statement for a period not to exceed 90 days in any 12 month period
if there exists at the time material non-public information relating to the
Company which, in the reasonable opinion of the Company, should not be disclosed
and the Company has provided Purchaser with prior written notice in writing of
such delay.

                  (d) Notwithstanding the foregoing paragraphs of this Section
7.5, Purchaser shall not be prohibited from selling Warrant Shares under the
Registration Statement as a result of Suspensions on more than two occasions of
not more than 30 days each in any twelve month period.

                                       13
<PAGE>

                  (e) Provided that a Suspension is not then in effect Purchaser
may sell Warrant Shares under the Registration Statement, provided that it
arranges for delivery of a current Prospectus to the transferee of such Warrant
Shares.

            7.6 Indemnification. For the purpose of this Section 7.6:

                  (a) the term "Selling Stockholder" shall include Purchaser and
any affiliate of Purchaser;

                  (b) the term "Registration Statement" shall include any final
Prospectus, exhibit, supplement or amendment included in or relating to the
Registration Statement referred to in Section 7.4; and

                  (c) the term "untrue statement" shall include any untrue
statement or alleged untrue statement, or any omission or alleged omission to
state in the Registration Statement a material fact required to be stated
therein or necessary to make the statements therein, in the light of the
circumstances under which they were made, not misleading.

                  (i) The Company agrees to indemnify and hold harmless each
            Selling Stockholder from and against any losses, claims, damages or
            liabilities to which such Selling Stockholder may become subject
            (under the Securities Act or otherwise) insofar as such losses,
            claims, damages or liabilities (or actions or proceedings in respect
            thereof) arise out of, or are based upon (i) any untrue statement of
            a material fact contained in the Registration Statement, or (ii) any
            failure by the Company to fulfill any undertaking included in the
            Registration Statement, and the Company will reimburse such Selling
            Stockholder promptly as incurred for any reasonable legal or other
            expenses reasonably incurred in investigating, defending or
            preparing to defend any such action, proceeding or claim, or
            preparing to defend any such action, proceeding or claim, provided,
            however, that the Company shall not be liable in any such case to
            the extent that such loss, claim, damage or liability arises out of,
            or is based upon, an untrue statement made in such Registration
            Statement in reliance upon and in conformity with written
            information furnished to the Company by or on behalf of such Selling
            Stockholder specifically for use in preparation of the Registration
            Statement or the failure of such Selling Stockholder to comply in
            all material respects with its covenants and agreements contained in
            Section 7 hereof respecting sale of the Warrant Shares or any
            statement or omission in any Prospectus that is corrected in any
            subsequent Prospectus that was delivered to Purchaser prior to the
            pertinent sale or sales by Purchaser.

                  (ii) Purchaser agrees to indemnify and hold harmless the
            Company (and each person, if any, who controls the Company within
            the meaning of Section 15 of the Securities Act, each officer of the
            Company who signs the Registration Statement and each director of
            the Company) from and against any losses, claims, damages or
            liabilities to which the Company (or any such officer, director or
            controlling person) may become subject (under the Securities Act or
            otherwise), insofar as such losses, claims, damages or liabilities
            (or actions or

                                       14
<PAGE>

            proceedings in respect thereof) arise out of, or are based upon, any
            untrue statement of a material fact contained in the Registration
            Statement or any Prospectus if such untrue statement was made in
            reliance upon and in conformity with written information furnished
            by or on behalf of Purchaser specifically for use in preparation of
            the Registration Statement or any Prospectus, provided, however,
            that Purchaser need not indemnify any of the aforementioned
            indemnitees for such losses, claims, damages or liabilities arising
            from any statement or omission in any Prospectus that is corrected
            in any subsequent Prospectus if the subsequent Prospectus was
            furnished to the person or entity asserting the loss, claim, damage
            or liability. Purchaser will reimburse the Company (or such officer,
            director or controlling person), as the case may be, for any legal
            or other expenses reasonably incurred in investigating, defending or
            preparing to defend any such indemnifiable action, proceeding or
            claim; provided that Purchaser's obligation to indemnify the Company
            shall be limited to the net amount received by Purchaser from the
            sale of the Warrant Shares.

                  (iii) Promptly after receipt by any indemnified person of a
            notice of a claim or the beginning of any action in respect of which
            indemnity is to be sought against an indemnifying person pursuant to
            this Section 7.6, such indemnified person shall notify the
            indemnifying person in writing of such claim or of the commencement
            of such action, but the omission to so notify the indemnifying party
            will not relieve it from any liability which it may have to any
            indemnified party under this Section 7.6 (except to the extent that
            such omission materially and adversely affects the indemnifying
            party's ability to defend such action) or from any liability
            otherwise than under this Section 7.6. Subject to the provisions
            hereinafter stated, in case any such action shall be brought against
            an indemnified person, the indemnifying person shall be entitled to
            participate therein, and, to the extent that it shall elect by
            written notice delivered to the indemnified party promptly after
            receiving the aforesaid notice from such indemnified party, shall be
            entitled to assume the defense thereof, with counsel reasonably
            satisfactory to such indemnified person. After notice from the
            indemnifying person to such indemnified person of its election to
            assume the defense thereof, such indemnifying person shall not be
            liable to such indemnified person for any legal expenses
            subsequently incurred by such indemnified person in connection with
            the defense thereof, provided, however, that if there exists or
            shall exist a conflict of interest that would make it inappropriate,
            in the opinion of counsel to the indemnified person, for the same
            counsel to represent both the indemnified person and such
            indemnifying person or any affiliate or associate thereof, the
            indemnified person shall be entitled to retain its own counsel at
            the expense of such indemnifying person; provided, however, that no
            indemnifying person shall be responsible for the fees and expenses
            of more than one separate counsel (together with appropriate local
            counsel) for all indemnified parties. In no event shall any
            indemnifying person be liable in respect of any amounts paid in
            settlement of any action unless the indemnifying person shall have
            approved the terms of such settlement; provided that such consent
            shall not be unreasonably withheld. No indemnifying person shall,
            without the prior written consent of the indemnified person, effect
            any settlement of any pending or threatened

                                       15
<PAGE>

            proceeding in respect of which any indemnified person is or could
            have been a party and indemnification could have been sought
            hereunder by such indemnified person, unless such settlement
            includes an unconditional release of such indemnified person from
            all liability on claims that are the subject matter of such
            proceeding.

                  (iv) If the indemnification provided for in this Section 7.6
            is unavailable to or insufficient to hold harmless an indemnified
            party under subsection (a) or (b) above in respect of any losses,
            claims, damages or liabilities (or actions or proceedings in respect
            thereof) referred to therein, then each indemnifying party shall
            contribute to the amount paid or payable by such indemnified party
            as a result of such losses, claims, damages or liabilities (or
            actions in respect thereof) in such proportion as is appropriate to
            reflect the relative fault of the Company on the one hand and
            Purchaser on the other in connection with the statements or
            omissions or other matters which resulted in such losses, claims,
            damages or liabilities (or actions in respect thereof), as well as
            any other relevant equitable considerations. The relative fault
            shall be determined by reference to, among other things, in the case
            of an untrue statement, whether the untrue statement relates to
            information supplied by the Company on the one hand or a Purchaser
            on the other and the parties' relative intent, knowledge, access to
            information and opportunity to correct or prevent such untrue
            statement. The Company and Purchaser agree that it would not be just
            and equitable if contribution pursuant to this subsection (d) were
            determined by pro rata allocation (even if Purchaser were treated as
            one entity for such purpose) or by any other method of allocation
            which does not take into account the equitable considerations
            referred to above in this subsection (d). The amount paid or payable
            by an indemnified party as a result of the losses, claims, damages
            or liabilities (or actions in respect thereof) referred to above in
            this subsection (d) shall be deemed to include any legal or other
            expenses reasonably incurred by such indemnified party in connection
            with investigating or defending any such action or claim.
            Notwithstanding the provisions of this subsection (d), Purchaser
            shall not be required to contribute any amount in excess of the
            amount by which the net amount received by Purchaser from the sale
            of the Warrant Shares to which such loss relates exceeds the amount
            of any damages which Purchaser has otherwise been required to pay by
            reason of such untrue statement. No person guilty of fraudulent
            misrepresentation (within the meaning of Section 11(f) of the
            Securities Act) shall be entitled to contribution from any person
            who was not guilty of such fraudulent misrepresentation. Purchaser'
            obligations in this subsection to contribute are several in
            proportion to their sales of Warrant Shares to which such loss
            relates and not joint.

                  (v) The parties to this Agreement hereby acknowledge that they
            are sophisticated business persons who were represented by counsel
            during the negotiations regarding the provisions hereof including,
            without limitation, the provisions of this Section 7.6, and are
            fully informed regarding said provisions. They further acknowledge
            that the provisions of this Section 7.6 fairly allocate the risks in
            light of the ability of the parties to investigate the Company and
            its

                                       16
<PAGE>

            business in order to assure that adequate disclosure is made in the
            Registration Statement as required by the Act and the Exchange Act.
            The parties are advised that federal or state public policy as
            interpreted by the courts in certain jurisdictions may be contrary
            to certain of the provisions of this Section 7.6, and the parties
            hereto hereby expressly waive and relinquish any right or ability to
            assert such public policy as a defense to a claim under this Section
            7.6 and further agree not to attempt to assert any such defense.

            7.7 Termination of Conditions and Obligations. The conditions
precedent imposed by this Section 7 upon the transferability of the Warrant
Shares shall cease and terminate as to any particular number of the Warrant
Shares (i) when such Warrant Shares shall have been effectively registered under
the Securities Act and sold or otherwise disposed of in accordance with the
intended method of disposition set forth in the Registration Statement covering
such Warrant Shares, or (ii) when such Warrant Shares are sold pursuant to Rule
144.

            7.8 Information Available. So long as the Registration Statement is
effective covering the resale of Warrant Shares owned by Purchaser, the Company
will furnish to Purchaser:

                  (a) as soon as practicable after it is available, one copy of
(i) its Annual Report to Stockholders (which Annual Report shall contain
financial statements audited in accordance with generally accepted accounting
principles by a national firm of certified public accountants), (ii) its Annual
Report on Form 10-K and amendments, if any, and (iii) its Quarterly Reports on
Form 10-Q and amendments, if any (the foregoing, in each case, excluding
exhibits);

                  (b) upon the request of Purchaser, all exhibits excluded by
the parenthetical to subparagraph (a) of this Section 7.8 as filed with the SEC
and all other information that is made available to shareholders; and

                  (c) upon the request of Purchaser, an adequate number of
copies of the Prospectuses to supply to any other party requiring such
Prospectuses; and the Company, upon the request of Purchaser, will meet with
Purchaser or a representative thereof at the Company's headquarters, or such
other mutually agreed upon location, to discuss all information relevant for
disclosure in the Registration Statement covering the Warrant Shares and will
otherwise cooperate with any Purchaser conducting an investigation for the
purpose of reducing or eliminating such Purchaser's exposure to liability under
the Securities Act, including the reasonable production of information at the
Company's headquarters.

      8.    COMPANY REPORTS FILED UNDER THE EXCHANGE ACT.

            With a view to making available to the Purchaser the benefits of
Rule 144 and other rules or regulations of the SEC that may permit the Purchaser
to sell Warrant Shares to the public without registration, the Company covenants
and agrees to: (a) make and keep public information available, as those terms
are understood and defined in Rule 144, at all times after the Closing; (b) file
with the SEC in a timely manner all reports and other documents required of the
Company under the Securities Act and the Exchange Act; and (c) furnish to the
Purchaser, so long as the Purchaser owns any Securities, forthwith upon request,
(i) a written statement by the

                                       17
<PAGE>

Company that it has complied with the reporting requirements of Rule 144, the
Securities Act and the Exchange Act, (ii) a copy of the most recent annual
report of the Company, and a copy of each quarterly and interim report of the
Company filed since the filing of the most recent annual report of the Company,
and (iii) such other information as may be reasonably requested in order to
avail the Purchaser of any rule or regulation of the SEC that permits the
selling of any such Securities without registration.

      9.    MISCELLANEOUS.

            9.1 Waivers and Amendments. The terms of this Agreement may be
waived or amended only with the written consent of the Company and Purchaser.

            9.2 Governing Law. This Agreement and the Warrant shall each be
construed and enforced in accordance with, and the rights of the parties shall
be governed by, the laws of the State of Delaware without regard to conflict of
laws.

            9.3 Survival. The representations, warranties, covenants and
agreements made herein shall survive any investigation made by the Company or
Purchaser and the Closing.

            9.4 Successors and Assigns. The provisions hereof shall inure to the
benefit of, and be binding upon, the successors, assigns, heirs, executors and
administrators of the parties hereto (specifically including any person that
becomes a Holder (as defined in the Warrant) of the Warrant through transfer
thereof from the Purchaser in accordance with the terms of the Warrant). In the
event of any merger, consolidation or acquisition involving the Company in which
the Company is not the surviving entity, the Company's obligations hereunder and
under the Warrant shall be expressly or by operation of law assumed by the
surviving entity.

            9.5 Entire Agreement. The Agreements constitute the full and entire
understanding and agreement between the parties with regard to the subject
hereof; provided, however, that nothing in the Agreements shall be deemed to
terminate or supersede the provisions of any confidentiality and disclosure
agreements executed by the parties hereto prior to the date hereof, which
agreements shall continue in full force and effect until terminated in
accordance with their respective terms.

            9.6 Notices, etc. All notices and other communications required or
permitted hereunder shall be effective upon receipt and shall be in writing and
may be delivered in person, by facsimile, overnight delivery service or U.S.
mail, in which event it may be mailed by first-class, certified or registered,
postage prepaid, addressed:

      if to Purchaser, at

                   Amgen Inc.
                   One Amgen Center Drive
                   Thousand Oaks, CA 91320-1789
                   Attention: Corporate Secretary
                   Fax: (805) 447-1010

                                       18
<PAGE>

      or

      if to the Company, at

                   ViaCell, Inc.
                   245 First Street
                   Cambridge, MA 02142
                   Attention: President
                   Fax:

      with a copy to

                   Ropes & Gray LLP
                   One International Place
                   Boston, MA 02110
                   Attention: Marc A. Rubenstein
                   Fax: 617-951-7050

or in any case at such other address as Purchaser or the Company shall have
furnished to the other in writing.

            9.7 Severability of this Agreement. If any provision of this
Agreement shall be judicially determined to be invalid, illegal or
unenforceable, the validity, legality and enforceability of the remaining
provisions shall not in any way be affected or impaired thereby.

            9.8 Delays or Omissions. No delay or omission to exercise any right,
power or remedy accruing to Company or to the Purchaser, upon any breach or
default of any party hereto under this Agreement, shall impair any such right,
power or remedy of Company or the Purchaser nor shall it be construed to be a
waiver of any such breach or default, or an acquiescence therein, or of any
similar breach of default thereafter occurring; nor shall any waiver of any
other breach or default theretofore or thereafter occurring. Any waiver, permit,
consent or approval of any kind or character on the part of Company or the
Purchaser of any breach of default under this Agreement or any waiver on the
part of Company or the Purchaser of any provisions or conditions of this
Agreement, must be in writing and shall be effective only to the extent
specifically set forth in such writing. All remedies, either under this
Agreement, or by law or otherwise afforded to Company or the Purchaser shall be
cumulative and not alternative.

            9.9 Titles and Subtitles. The titles of the paragraphs and
subparagraphs of this Agreement are for convenience of reference and shall not,
by themselves, determine the construction of this Agreement.

            9.10 Counterparts. This Agreement may be executed in any number of
counterparts, each of which shall be an original, but all of which together
shall constitute one instrument.

                                       19
<PAGE>

            9.11 Remedies. In addition to being entitled to exercise all rights
provided herein or granted by law, including recovery of damages, each of the
Purchaser and the Company will be entitled to specific performance under this
Agreement and the Warrant. The parties agree that monetary damages may not be
adequate compensation for any loss incurred by reason of any breach of
obligations described in the foregoing sentence and hereby agrees to waive in
any action for specific performance of any such obligation the defense that a
remedy at law would be adequate.

            9.12 Attorneys' Fees. In any action or proceeding brought to enforce
any provision of this Agreement, or where any provision hereof is validly
asserted as a defense, the successful party shall be entitled to recover
reasonable attorneys' fees in addition to its costs and expenses and any other
available remedy.

            9.13 Finder's Fee. Each party represents that it neither is nor will
be obligated for any finder's fee or commission in connection with this
transaction. The Purchaser agrees to indemnify and to hold harmless the Company
from any liability for any commission or compensation in the nature of a
finder's fee (and the costs and expenses of defending against such liability or
asserted liability) for which the Purchaser or any of its officers, employees,
or representatives is responsible. The Company agrees to indemnify and hold
harmless the Purchaser from any liability for any commission or compensation in
the nature of a finder's fee (and the costs and expenses of defending against
such liability or asserted liability) for which the Company or any of its
officers, employees or representatives is responsible.

                            [signature page follows]

                                       20
<PAGE>

            IN WITNESS WHEREOF, the parties hereto have caused their respective
duly authorized representatives to execute this Agreement as of the date and
year first above written.

VIACELL, INC.                                  AMGEN INC.

/s/ Marc D. Beer                               /s/ Scott J. Foraker
____________________________________           _________________________________
By: Marc D. Beer                               By: Scott J. Foraker, Esq.
Title: Chief Executive Officer                 Title: Vice President, Licensing

                 [Signature Page to Warrant Purchase Agreement]

<PAGE>

                                                                     Exhibit 1.1

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT
AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933. THE SECURITIES
MAY NOT BE SOLD OR TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN
EXEMPTION THEREFROM. THE SECURITIES REPRESENTED BY THIS CERTIFICATE AND THE
RIGHTS OF THE HOLDER HEREOF ARE SUBJECT TO CERTAIN RESTRICTIONS ON TRANSFER AND
OTHER RESTRICTIONS, AND THE HOLDER OF THE SECURITIES REPRESENTED BY THIS
CERTIFICATE (INCLUDING ANY FUTURE HOLDER) IS BOUND BY THE TERMS OF A WARRANT
PURCHASE AGREEMENT BETWEEN THE ORIGINAL PURCHASER AND THE COMPANY (COPIES OF
WHICH MAY BE OBTAINED FROM THE COMPANY).

             WARRANT TO PURCHASE 200,000 SHARES OF COMMON STOCK OF
                                  VIACELL, INC.

      This certifies that the holder hereof (the "Holder"), for value received,
is entitled to purchase from ViaCell, Inc., a Delaware corporation (the
"Company"), Two Hundred Thousand (200,000) fully paid and nonassessable shares
(the "Warrant Shares") of the Company's common stock, par value $0.01 per share
(the "Common Stock"), at a price of $_____ per share (the "Stock Purchase
Price") pursuant to that certain Warrant Purchase Agreement between the Company
and Purchaser, dated as of August 29, 2005 (the "Warrant Purchase Agreement") at
any time on or after the date the Company first administers a G-CSF Product (as
defined in that certain Amendment No.1 to the Collaboration Agreement (the
"Amendment") by and between the Company and Holder) in Phase II Clinical Trials
(the "Vesting Date"), up to and including 5:00 p.m. (California time) on the
Expiration Date (as defined below), upon (a) surrender to the Company at its
principal offices at 245 First Street, Cambridge, Massachusetts 02142 (or at
such other location as the Company may advise the Holder in writing) of this
Warrant properly endorsed with the Notice of Conversion attached hereto duly
completed and signed, and (b) payment of the aggregate Stock Purchase Price for
the Warrant Shares. The Stock Purchase Price and the number of shares
purchasable hereunder are subject to adjustment as provided in Section 3 of this
Warrant. "Expiration Date" shall mean August 29, 2012 (or, in the event that
August 29, 2012 is not a business day, the next succeeding business day).

      This Warrant may be exercised as a whole or may be exercised in part or
from time to time at any time after the Vesting Date.

      This Warrant is issued pursuant to, and subject of the provisions of, the
Warrant Purchase Agreement and, by its acceptance of this Warrant, the Holder
expressly agrees to comply with the provisions of the Warrant Purchase
Agreement. Terms used but not defined in this Warrant shall have the respective
meanings assigned to them in the Warrant Purchase Agreement, to which reference
is hereby made.

                                  Exhibit 1.1-1
<PAGE>

      This Warrant is subject to the following further terms and conditions:

      1.    EXERCISE.

            Exercise Procedure; Issuance of Certificates; Payment for Shares.
This Warrant is exercisable at the option of the Holder at any time on or after
the Vesting Date and prior to or on the Expiration Date for the Warrant Shares
which may be purchased hereunder. The Company agrees that the Warrant Shares
purchased under this Warrant shall be and are deemed to be issued to the Holder
as the record owner of such shares as of the close of business on the date on
which this Warrant shall have been surrendered and payment made for such shares.
Subject to the provisions of Section 2 hereof, certificates for the Warrant
Shares so purchased, together with any other securities or property to which the
Holder is entitled upon such exercise, shall be delivered to the Holder by the
Company's transfer agent at the Company's expense within a reasonable time after
the rights represented by this Warrant have been exercised. Each stock
certificate so delivered shall be in such denominations of Warrant Shares as may
be requested by the Holder and shall be registered in the name of the Holder.

            If the Warrant shall be converted for less than the total number of
shares of Warrant Shares then issuable upon conversion, promptly after surrender
of the Warrant upon such conversion, the Company will execute and deliver a new
warrant, dated the date hereof, evidencing the right of the Holder to the
balance of the Warrant Shares purchasable hereunder upon the same terms and
conditions set forth herein. If this Warrant is converted, as a whole or in
part, after the occurrence of an event as to which Section 3.8 is applicable,
the Holder shall receive the consideration contemplated by Section 3.8 in lieu
of Common Stock of the Company.

      2.    SHARES TO BE FULLY PAID; RESERVATION OF SHARES.

            The Company covenants and agrees that all Warrant Shares which may
be issued upon the exercise of this Warrant will, upon issuance, be validly
issued, fully paid and nonassessable and free from all preemptive or any similar
rights of any stockholder of the Company and free of any liens or encumbrances
arising through the Company, other than restrictions of transfer under the
Warrant Purchase Agreement, this Warrant and applicable state and federal
securities laws. The Company further covenants and agrees that during the period
within which this Warrant may be exercised the Company will at all times have
authorized and reserved, for the purpose of issue or transfer upon exercise of
this Warrant, a sufficient number of authorized but unissued shares of Common
Stock, when and as required to provide for the exercise of the rights
represented by this Warrant. The Company will take all such action as may be
necessary to assure that such shares of Common Stock may be issued as provided
herein without violation of any applicable law or regulation, or of any
requirements of any domestic securities exchange or automated quotation system
upon which the Common Stock is listed.

      3.    ADJUSTMENT OF STOCK PURCHASE PRICE AND NUMBER OF WARRANT SHARES
            ISSUABLE.

            The Stock Purchase Price and the number of Warrant Shares issuable
upon the exercise of each Warrant are subject to adjustment from time to time
upon the occurrence of the events enumerated in this Section 3.

                                  Exhibit 1.1-2
<PAGE>

            3.1 Adjustment for Change in Capital Stock. If the Company: (i) pays
a dividend or makes a distribution on its Common Stock in shares of its Common
Stock; (ii) subdivides its outstanding shares of Common Stock into a greater
number of shares; or (iii) combines its outstanding shares of Common Stock into
a smaller number of shares; then the Stock Purchase Price in effect immediately
prior to such action shall then be adjusted in accordance with the formula:

             E(1) = E x O/A

 where:

             E(1) = the adjusted Stock Purchase Price.

             E    = the current Stock Purchase Price.

             O    = the number of shares of Common Stock outstanding prior to
                    such action.

             A    = the number of shares of Common Stock outstanding immediately
                    after such action.

            (a) In the case of a dividend or distribution the adjustment shall
become effective immediately after the record date for determination of holders
of shares of Common Stock entitled to receive such dividend or distribution, and
in the case of a subdivision or combination, the adjustment shall become
effective immediately after the effective date of such corporate action.

            (b) If after an adjustment the Holder of the Warrant upon exercise
of it may receive shares of two or more classes of capital stock of the Company,
the Company shall determine the allocation of the adjusted Stock Purchase Price
between the classes of capital stock. After such allocation, the exercise
privilege, the number of shares issuable upon such exercise, and the Stock
Purchase Price of each class of capital stock shall thereafter be subject to
adjustment on terms comparable to those applicable to Common Stock in this
Section 3.

            (c) Such adjustment shall be made successively whenever any event
listed above shall occur.

                                  Exhibit 1.1-3
<PAGE>

            3.2 Adjustment for Rights Issue. If the Company distributes any
rights, options or warrants to all holders of its Common Stock entitling them at
any time after the record date mentioned below to purchase shares of Common
Stock at a price per share less than the Fair Market Value (as defined in
Section 3.4) per share of Common Stock on that record date, the Stock Purchase
Price shall be adjusted in accordance with the formula:

    E(1)  = E x (O + (N x P)/M)/(O + N)

where:

    E(1)  = the adjusted Stock Purchase Price.

    E     = the current Stock Purchase Price.

    O     = the number of shares of Common Stock outstanding on the record date.

    N     = the number of additional shares of Common Stock issuable upon
            exercise of the rights, options or warrants offered.

    P     = the exercise price per share of the additional shares issuable upon
            exercise of the rights, options or warrants.

    M     = the Fair Market Value per share of Common Stock on the record date.

The adjustment shall be made successively whenever any such rights, options or
warrants are issued and shall become effective immediately after the record date
for the determination of stockholders entitled to receive the rights, options or
warrants. If at the end of the period during which such rights, options or
warrants are exercisable, not all rights, options or warrants shall have been
exercised, the Stock Purchase Price shall be immediately readjusted to what it
would have been if "N" in the above formula had been the number of shares
actually issued.

            3.3 Adjustment for Other Distributions. If the Company distributes
to all holders of its Common Stock any of its assets (including but not limited
to cash and securities), the Stock Purchase Price shall be adjusted in
accordance with the formula:

   E(1) = E x (M - F)/M

where:

   E(1) = the adjusted Stock Purchase Price.

   E    = the current Stock Purchase Price.

                                  Exhibit 1.1-4
<PAGE>

   M = the Fair Market Value per share of Common Stock on the record date
       mentioned below.

   F = the fair market value on the record date of the assets, debt securities,
       capital stock or rights or warrants applicable to one share of Common
       Stock. The Board of Directors shall determine the fair market value.

The adjustment shall be made successively whenever any such distribution is made
and shall become effective immediately after the record date for the
determination of stockholders entitled to receive the distribution.

      This subsection does not apply to non-extraordinary quarterly cash
dividends distributed to all holders of Common Stock.

            3.4 Fair Market Value. As used in this Agreement, the "Fair Market
Value" per share of Common Stock on any date is (i) if the Common Stock is not
at the time of such determination publicly traded, the fair market value as
determined in good faith by the Board of Directors of the Company or (ii) if the
Common Stock is at the time of such determination publicly traded, the market
price of the Common Stock (the market price determined, for any date, as the
average of the closing prices of the Common Stock on the Nasdaq National Market
(or such other principal securities exchange or automated quotation system upon
which the Common Stock may then be listed for public trading) for the five
immediately preceding trading days on such exchange.

            3.5 When Adjustments May Be Deferred. No adjustment in the Stock
Purchase Price need be made unless the adjustment would require an increase or
decrease of at least 1% in the Stock Purchase Price. Any adjustments that are
not made shall be carried forward and taken into account in any subsequent
adjustment. All calculations under this Section shall be made to the nearest
cent or to the nearest 1/100th of a share, as the case may be.

            3.6 No Adjustment Required. No adjustment need be made for a
transaction referred to in subsections 3.1 through 3.3 if:

            (a) Warrant holders are to participate in the transaction on a basis
and with notice that the Board of Directors determines to be fair and
appropriate in light of the basis on which holders of Common Stock participate
in the transaction. Further, no adjustment need be made for rights to purchase
Common Stock pursuant to a Company plan for reinvestment of dividends or
interest; or

            (b) there is a change in the par value or no par value of the Common
Stock; or

            (c) the Company distributes or issues rights to all holders of its
Common Stock pursuant to a stockholder rights plan, provided that, upon exercise
of the Warrant, each holder thereof receives the same type and number of
unexpired rights it would have received (as adjusted for any event described in
Section 3.1 or 3.8) had it exercised its Warrant, and been a holder of the
Warrant Shares issuable upon exercise thereof, prior to the record date for such
distribution or issuance; or

                                  Exhibit 1.1-5
<PAGE>

            (d) the Warrant becomes convertible into cash, no adjustment need be
made thereafter as to the cash and interest will not accrue on the cash.

            3.7 Notice of Adjustment. Whenever the Stock Purchase Price is
adjusted, the Company shall provide the notices required by Section 8 hereof.

            3.8 Reorganization of Company. If any reclassification of the Common
Stock of the Company or any consolidation or merger of the Company with another
entity, or the sale or lease of all or substantially all of the Company's assets
to another entity shall be effected in such a way that holders of the Common
Stock of the Company shall be entitled to receive stock, securities or assets
with respect to or in exchange for such Common Stock, then, as a condition
precedent to such reclassification, consolidation, merger, sale or lease, lawful
and adequate provisions shall be made whereby the Warrant holder shall
thereafter have the right to purchase and receive upon the basis and the terms
and conditions specified in this Warrant and in lieu of the shares of Common
Stock immediately theretofore purchasable and receivable upon the exercise of
the rights represented hereby, such shares of stock, securities or assets as may
be issued or payable in such reclassification, consolidation, merger, sale or
lease with respect to or in exchange for the number of shares of Common Stock
purchasable and receivable upon the exercise of the rights represented hereby
had such rights been exercised immediately prior thereto, and in any such case
appropriate provision shall be made with respect to the rights and interests of
the holders of the Warrant to the end that the provisions hereof (including
without limitation provisions for adjustments of the Stock Purchase Price and of
the number of shares of Common Stock purchasable and receivable upon the
exercise of the Warrant) shall thereafter be applicable, as nearly as may be, in
relation to any shares of stock, securities or assets thereafter deliverable
upon the exercise hereof. The Company will not effect any such reclassification,
consolidation, merger, sale or lease, unless prior to the consummation thereof
the successor corporation (if other than the Company) resulting from such
reclassification, consolidation or merger or the corporation purchasing or
leasing such assets shall assume by a supplemental Warrant Agreement, executed
and mailed or delivered to the holders of the Warrant at the last address
thereof appearing on the books of Company, the obligation to deliver to such
holders such shares of stock, securities or assets as, in accordance with the
foregoing provisions, such holders may be entitled to purchase.

            (a) If the issuer of securities deliverable upon exercise of
Warrants under the supplemental Warrant Agreement is an affiliate of the formed,
surviving, transferee or lessee corporation, that issuer shall join in the
supplemental Warrant Agreement.

            (b) If this subsection 3.8 applies, subsections 3.1 through 3.3 do
not apply.

            3.9 When Issuance or Payment May Be Deferred. In any case in which
this Section 3 shall require that an adjustment in the Stock Purchase Price be
made effective as of a record date for a specified event, the Company may elect
to defer until the occurrence of such event (i) issuing to the holder of any
Warrant exercised after such record date the Warrant Shares and other capital
stock of the Company, if any, issuable upon such exercise over and above the
Warrant Shares and other capital stock of the Company, if any, issuable upon
such exercise on the basis of the Stock Purchase Price and (ii) paying to such
holder any amount in cash in lieu of a fractional share pursuant to Section 11;
provided, however, that the Company shall deliver to

                                  Exhibit 1.1-6
<PAGE>

such holder a due bill or other appropriate instrument evidencing such holder's
right to receive such additional Warrant Shares, other capital stock and cash
upon the occurrence of the event requiring such adjustment.

            3.10 Adjustment in Number of Shares. Upon each adjustment of the
Stock Purchase Price pursuant to Section 3.1 or 3.2, the Warrant outstanding
prior to the making of the adjustment in the Stock Purchase Price shall
thereafter evidence the right to receive upon payment of the adjusted Stock
Purchase Price that number of shares of Common Stock (calculated to the nearest
hundredth) obtained from the following formula:

              N(1) = N x E/E(1)

where:

              N(1) = the adjusted number of Warrant Shares issuable upon
                     exercise of a Warrant by payment of the adjusted Stock
                     Purchase Price.

              N    = the number of Warrant Shares previously issuable upon
                     exercise of a Warrant by payment of the Stock Purchase
                     Price prior to adjustment.

              E(1) = the adjusted Stock Purchase Price.

              E    = the Stock Purchase Price prior to adjustment.

There shall be no adjustment in the number of shares of Common Stock that the
Warrant evidences the right to receive in the case of any adjustment to the
Stock Purchase Price pursuant to Section 3.3.

            3.11 Form of Warrant. Irrespective of any adjustments in the Stock
Purchase Price or the number or kind of shares purchasable upon the exercise of
the Warrant, any Warrant theretofore or thereafter issued may continue to
express the same price and number and kind of shares as are stated in the
Warrant initially issuable.

      4.    ISSUANCES AND TRANSFER TAXES.

            The issuance of certificates in the name of the Holder for the
Warrant Shares upon the exercise of this Warrant shall be made without charge to
the Holder of this Warrant for any issue tax in respect thereof. The Holder
shall pay all stock transfer taxes, if any, in respect of any transfer of this
Warrant or any Warrant Shares.

      5.    NO VOTING OR DIVIDEND RIGHTS; LIMITATION OF LIABILITY.

            Nothing contained in this Warrant shall be construed as conferring
upon the Holder hereof the right to vote or to consent or to receive notice as a
stockholder in respect of meetings of stockholders for the election of directors
of the Company or any other matters or any rights whatsoever as a stockholder of
the Company. Except for the adjustment to the Stock

                                  Exhibit 1.1-7
<PAGE>

Purchase Price pursuant to Section 3.1 hereof in the event of a dividend on the
Common Stock payable in shares of Common Stock, no dividends or interest shall
be payable or accrued in respect of this Warrant or the interest represented
hereby or the shares purchasable hereunder until, and only to the extent that,
this Warrant shall have been exercised.

      6.    RESTRICTIONS ON TRANSFERABILITY OF SECURITIES.

            6.1 Restrictions on Transfer of Warrant Shares. The Holder shall not
sell Warrant Shares, either under a registration statement or otherwise, until
after a 31 day period from the date of exercise of the Warrant Shares to be
sold. The Warrant Shares shall not be transferable except upon the conditions
specified in the Warrant Purchase Agreement.

            6.2 Transferees Bound by Warrant. Subject to compliance with the
other provisions of this Section 6, the Holder may sell this Warrant or the
Warrant Shares in accordance with applicable law; provided, however, that the
transferee of such security shall be bound by all the terms and provisions of
this Warrant and no sale shall be valid unless such transferee consents in
writing to be bound by the terms of this Warrant.

            6.3 Transfers in Violation of Warrant. Any sale or attempted sale of
this Warrant or the Warrant Shares in violation of any provision of this Warrant
shall be void, and the Company shall not record such sale on its books nor treat
any purported transferee of such securities as the owner of such securities for
any purpose.

      7.    MODIFICATION AND WAIVER.

            This Warrant and any provision hereof may be changed, waived,
discharged or terminated only by an instrument in writing signed by the party
against which enforcement of the same is sought.

      8.    NOTICES.

            All notices and other communications required or permitted hereunder
shall be effective upon receipt and shall be in writing and may be delivered in
person, by facsimile, overnight delivery service or U.S. mail, in which event it
may be mailed by first-class, certified or registered, postage prepaid,
addressed:

      if to the Holder, at

            Amgen Inc.
            One Amgen Center Drive
            Thousand Oaks, CA 91320-1789
            Attention: Corporate Secretary
            Fax: (805) 447-1010

      or

                                  Exhibit 1.1-8
<PAGE>

      if to the Company, at

            ViaCell, Inc.
            245 First Street
            Cambridge, MA 02142
            Attention: President
            Fax:

      With a copy to

            Ropes & Gray LLP
            One International Place
            Boston, MA 02110
            Attention: Marc A. Rubenstein
            Fax: 617-951-7050

or in any case at such other address as the Holder or the Company shall have
furnished to the other in writing.

      9.    DESCRIPTIVE HEADINGS AND GOVERNING LAW.

            The descriptive headings of the Sections and paragraphs of this
Warrant are inserted for convenience only and do not constitute a part of this
Warrant. This Warrant shall be construed and enforced in accordance with, and
the rights of the parties shall be governed by, the laws of the State of
Delaware without regard to conflict of laws.

      10.   LOST WARRANTS OR STOCK CERTIFICATES.

            The Company represents and warrants to the Holder that upon receipt
of evidence reasonably satisfactory to the Company of the loss, theft,
destruction, or mutilation of any Warrant or stock certificate and, in the case
of any such loss, theft or destruction, upon receipt of an indemnity and, if
requested, bond reasonably satisfactory to the Company, or in the case of any
such mutilation upon surrender and cancellation of such Warrant or stock
certificate, the Company at its expense will make and deliver a new Warrant or
stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or
mutilated Warrant or stock certificate.

      11.   FRACTIONAL SHARES.

            No fractional shares shall be issued upon exercise of this Warrant.
The Company shall, in lieu of issuing any fractional share, pay the Holder
entitled to such fraction a sum in cash equal to such fraction multiplied by (i)
if the Common Stock is not at the time of such determination publicly traded,
the fair market value as determined in good faith by the Board of Directors of
the Company or (ii) if the Common Stock is at the time of such determination
publicly traded, the market price of the Common Stock (the market price
determined, for any date, as the average of the closing prices of the Common
Stock on the Nasdaq National Market (or such other principal securities exchange
or automated quotation system upon which the Common Stock may then be listed for
public trading) for the five immediately preceding trading days on such
exchange).

                                  Exhibit 1.1-9
<PAGE>

      12.   NO IMPAIRMENT.

            The Company will not, by amendment of its Certificate of
Incorporation or bylaws, or through reorganization, consolidation, merger,
dissolution, issue or sale of securities, sale of assets 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 of this Warrant against
impairment. Without limiting the generality of the foregoing, the Company (a)
will not increase the par value of any shares of stock issuable upon the
exercise of this Warrant above the amount payable therefor upon such exercise,
and (b) will take all such action as may be necessary or appropriate in order
that the Company may validly and legally issue fully paid and non-assessable
shares of Common Stock upon exercise of this Warrant.

                                 Exhibit 1.1-10
<PAGE>

      IN WITNESS WHEREOF, the Company has caused this Warrant to be executed by
its officers, thereunto duly authorized this 29th day of August, 2005.

                                     VIACELL, INC.

                                     ___________________________________________
                                     By: Marc D. Beer
                                     Title: Chief Executive Officer

                           [Signature Page to Warrant]

<PAGE>

                              NOTICE OF CONVERSION

      (To be signed only upon exercise of Warrant)

      To: ViaCell, Inc.

            The undersigned, the Holder of the within Warrant, hereby
irrevocably elects to exercise the purchase right represented by such Warrant
for, and to purchase thereunder, _________________ shares of common stock, par
value $0.01 per share, of ViaCell, Inc. (the "Company") and herewith makes
payment therefor in cash by remitting $________ and requests that the
certificates for such shares be issued in the name of, and delivered to,

_______________________________________________________________________________
_______________________________________________________________________________
whose address is ______________________________________________________________.

            Capitalized terms used but not defined herein shall have the
meanings ascribed to such terms in the Warrant.

            DATED:___________________

                                        AMGEN INC.

                                        _______________________________________
                                        By ____________________________________
                                        Title__________________________________

<PAGE>

                                                                     Exhibit 1.2

                                    AMENDMENT

<PAGE>

                                                                     Exhibit 3.7

                           OPINION OF COMPANY COUNSEL

      1. The Company is validly existing as a corporation and is in good
standing under Delaware law and has the corporate power and authority to execute
and deliver the Agreements and to perform its obligations thereunder. The
Company is duly qualified as a foreign corporation authorized to do business in
Massachusetts.

      2. The Company has duly authorized, executed and delivered the Agreements
and the Agreements constitute valid and binding obligations of the Company
enforceable against it in accordance with their terms.

      3. The Warrant Shares have been duly authorized and reserved for issuance
by the Company and, when issued, sold and delivered in accordance with the terms
of the Warrant, will be duly authorized and validly issued, fully paid and
nonassessable.

      4. The execution and delivery by the Company of the Agreements and the
issuance of the Warrant and the Warrant Shares thereunder, do not, and the
performance by it of its obligations thereunder will not (i) violate any
applicable law covered by this opinion or any court order, judgment or decree
specifically naming the Company and known to us, (ii) result in a violation of
or constitute a default under or breach of, or result in the creation of a lien
or a right of acceleration under, any material agreements or instruments filed
in connection with the SEC Documents or (iii) violate its Certificate of
Incorporation or by-laws.

      5. Except for such post-closing filings as may be required after the date
hereof under applicable federal and state securities laws, which filings will
need to be made within the requisite period, no consent, approval, license or
exemption by, or order or authorization of, or filing, recording or registration
with, any governmental authority is required to be obtained by the Company in
connection with the execution and delivery of the Agreements, or the performance
by the Company of its obligations thereunder.

      6. Based on the representations of the Purchaser in the Purchase
Agreement, the offer, issuance and sale of the Warrant (and the Warrant Shares
issued upon due exercise thereof, if so issued to the Purchaser as of the date
of this opinion) in the manner contemplated by the Purchase Agreement and the
Warrant are exempt from the registration requirements of the Securities Act of
1933, as amended, and of the Massachusetts Uniform Securities Act.

      7. To our knowledge, no action, suit or proceeding to which the Company is
a party is pending or is overtly threatened in writing against the Company that
places in question the validity or enforceability of, or seeks to enjoin the
performance of, the Agreements.

<PAGE>

                                                                       Exhibit 5

                             SCHEDULE OF EXCEPTIONS

                                      NONE.