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CONFIDENTIAL

                                                                    EXHIBIT 10.1

CERTAIN CONFIDENTIAL INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY
BRACKETS([**]), HAS BEEN OMITTED AND FILED SEPARATELY WITH THE SECURITIES AND
EXCHANGE COMMISSION PURSUANT TO RULE 24b-2 OF THE SECURITIES ACT OF1933, AS
AMENDED

                              DEVELOPMENT AGREEMENT

      This DEVELOPMENT AGREEMENT (this "Agreement") is entered into as of
January 24, 2005 (the "Effective Date"), by and between Miltenyi Biotec GmbH,
having an address of Friedrich-Ebert-Str. 68, D-51429 Bergisch Gladbach, Germany
("MILTENYI") and ViaCell, Inc., having an address of 245 First Street, Fifteenth
Floor, Cambridge, MA 02142-1292 USA (including its Affiliates), ("VIACELL").

      WHEREAS, MILTENYI has expertise in providing technology and technical
development capabilities and MILTENYI has developed systems, including the
CliniMACS(R) System, for separating certain cells from a mixture containing such
cells and other cells;

      WHEREAS MILTENYI has expertise in U.S. regulatory matters, including
filing Master Files with the U.S. Food and Drug Administration ("FDA") and cGMP
compliance;

      WHEREAS, VIACELL is seeking a development partner who can develop
cGMP-cell separation reagents for use with VIACELL's stem cell selection and
amplification system and

      WHEREAS, the parties desire to enter into a development agreement as set
forth herein pursuant to which MILTENYI will provide certain technology and
technical development and regulatory capabilities for VIACELL by developing
certain cGMP cell separation reagents for VIACELL for purchase under a separate
Supply Agreement between MILTENYI and ViaCell, Inc.

      NOW, THEREFORE, in consideration of the mutual covenants contained herein,
and for other good and valuable consideration, the parties hereto, intending to
be legally bound, hereby agree as follows:

                                 1. DEFINITIONS

Whenever used in this Agreement with an initial capital letter, the terms
defined in this Section 1 shall have the meanings specified.

1.1 "AFFILIATE" means any corporation, firm, partnership or other entity which
directly or indirectly controls or is controlled by or is under common control
with a Party to this Agreement. "Control" means ownership, directly or through
one or more Affiliates, or fifty percent (50%) or more of the shares of stock
entitled to vote for the election of directors, in the case of a corporation, or
fifty percent (50%) or more of the equity interests in the case of any other
type of legal entity, status as a general partner in any partnership, or any
other arrangement whereby a Party controls or has the right to control the Board
of Directors or equivalent governing body of a corporation or other entity.

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1.2 "CELL SEPARATION KIT" means a product consisting of [**], which is
sufficient to deplete [**] and includes cGMP Cell Separation Kit.

1.3 "cGMP" means the current safety and performance specifications, guidelines,
and regulations with which MILTENYI's CliniMACS [**] currently comply. These
specifications, guidelines and regulations consist of the 1997 FDA document
Points to Consider in the Manufacture and Testing of Monoclonal Antibodies
Products for Human Use, the ICH harmonized tripartite guideline Q5A: Viral
Safety Evaluation of Biotechnology Products Derived from Cell Lines of Human or
Animal Origin, and the ISO standard 10993-1:1997 (E) Biological evaluation of
medical devices - Part 1: Evaluation and testing. Additionally, the manufacture,
testing and release of the CliniMACS [**], CliniMACS [**] and CliniMACS [**] are
conducted under an ISO 13485 certified quality system and the manufacture,
testing and release of CliniMACs [**] and CliniMACs [**] will also be conducted
under the same quality system as the CliniMACS [**] CliniMACS [**] and CliniMACS
[**].

1.4 "cGMP CELL SEPARATION KIT" means a Cell Separation Kit manufactured pursuant
to cGMP.

1.5 "CLINICAL STUDIES" means the clinical trials utilizing the Cell Separation
Kits.

1.6 "CLINIMACS BUFFERS" means the buffers developed by MILTENYI for use in the
CliniMACS System.

1.7 "CLINIMACS REAGENT" means MILTENYI's proprietary colloidal magnetic particle
system utilizing a monoclonal antibody developed by MILTENYI for use in the
CliniMACS system and to deplete certain cells in a mixture.

1.8 [**] means the CliniMACS Reagent where the monoclonal antibody is an
antibody to a [**] cell surface marker.

1.9 CLINIMACS [**] means the CliniMACS Reagent where the monoclonal antibody is
an antibody to a [**] cell surface marker.

1.10 "CLINIMACS [**]" means the CliniMACS Reagent where the monoclonal antibody
is an antibody to a [**] cell surface marker.

1.11 "CLINIMACS [**]" means the CliniMACS Reagent where the monoclonal antibody
is an antibody to a [**] cell surface marker.

1.12 "CLINIMACS [**]" means the CliniMACS Reagent where the monoclonal antibody
is an antibody to a [**] cell surface marker.

1.13 "CLINIMACS SYSTEM" means that system developed by MILTENYI for conducting
cell separation by use of CliniMACS Reagents, CliniMACS Tubing Sets and the
Instrument.

1.14 "CLINIMACS TUBING SETS" means the tubing and related disposable equipment
developed by MILTENYI for use with the CliniMACS Instrument.

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CONFIDENTIAL

1.15 "CONFIDENTIAL INFORMATION" means all tangible embodiments of Technology and
all information (including but not limited to information about any element of
Technology) which is disclosed by one Party to the other hereunder except to the
extent that such information (i) as of the date of disclosure is demonstrably
known to the Party receiving such disclosure or its Affiliates, as shown by
written documentation, other than by virtue of a prior confidential disclosure
to such Party or its Affiliates; (ii) as of the date of disclosure is in, or
subsequently enters, the public domain, through no fault or omission of the
Party receiving such disclosure; or (iii) as of the date of disclosure or
thereafter is obtained from a Third Party free from any obligation of
confidentiality to the disclosing Party.

1.16 "DEVELOPMENT MILESTONE PAYMENTS" has the meaning set forth in Section
2.2.4.

1.17 "DEVELOPMENT PROGRAM" has the meaning set forth in Section 2.2.

1.18 "EFFECTIVE DATE" means the date set forth in the first paragraph above.

1.19 "INSTRUMENT" means the CliniMACS(R) instrument developed by MILTENYI for
conducting the separation of cells labeled with CliniMACS Reagent from other
cells, and consisting primarily of a magnetized column through which such cells
pass and certain related equipment or another instrument the Parties may decide
to develop at a later time.

1.20 "JOINT PATENT RIGHTS" means Patent Rights with respect to Joint Technology.

1.21 "JOINT TECHNOLOGY" has the meaning set forth in Section 4.1.3.

1.22 "VIACELL TECHNOLOGY" means Technology owned or controlled by VIACELL or its
Affiliates, that is useful in the Development Program, and that was conceived or
developed without contribution by MILTENYI, and independently of the MILTENYI
Technology or Joint Technology.

1.23 "MASTER FILE" means a Device Master File filed by MILTENYI with the FDA.

1.24 "MILTENYI TECHNOLOGY" means Technology owned or controlled by MILTENYI or
its Affiliates, and that was conceived or developed without contribution by
VIACELL, and independently of the VIACELL Technology of Joint Technology.

1.25 "PARTIES" means MILTENYI and VIACELL.

1.26 "PARTY" means MILTENYI or VIACELL, as appropriate.

1.27 "PATENT RIGHTS" means the rights and interests in and to issued patents and
pending patent applications (which for purposes of this Agreement shall be
deemed to include certificates of invention and applications for certificate of
invention and priority rights) in any country, including all provisional
applications, substitutions, continuations, continuations-in-part, divisions,
and renewals, all letters patent granted thereon, and all reissues,
reexaminations and extensions thereof, whether owned or licensed in by a Party
with the right to sublicense. As used herein, "VIACELL Patent Rights" means
Patent Rights with respect to VIACELL Technology and "MILTENYI Patent Rights"
means Patent Rights with respect to MILTENYI Technology.

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1.28 "SPECIFICATIONS" are the criteria by which the Cell Separation Kit is
released and accepted, including the configuration of the packaging that
comprises the Cell Separation Kit. The criteria will be agreed to by the
Operating Committee. Such criteria may be modified by the Parties from time to
time as agreed to by the Operating Committee until MILTENYI begins any part of
the production process for product falling within the scope of Section 3.2 of
the Supply Agreement ("Second Product Shipment"), however, the Parties recognize
that VIACELL may be required to pay additional fees for any modifications to
criteria.

1.29 "SUPPLY AGREEMENT" means the Supply Agreement entered into between MILTENYI
and ViaCell, Inc. effective January 24, 2005.

1.30 "TECHNOLOGY" means and includes all inventions, discoveries, improvements,
trade secrets and proprietary methods and materials, whether or not patentable,
including but not limited to, samples of, methods of production or use of, and
structural and functional information pertaining to, chemical compounds,
proteins or other biological substances; other date; formulations; techniques;
and know-how; including any negative results. "Technology" of a Party includes
Technology owned or controlled by a Party or licensed to that Party.

1.31 "TERM" means the term of this Agreement as set forth in Section 6.1.

1.32 "THIRD PARTY" means any person or entity other than MILTENYI and VIACELL
and their respective Affiliates.

                             2. DEVELOPMENT PROGRAM

2.1 OBJECTIVE OF THE DEVELOPMENT PROGRAM. The objective of the Development
Program shall be the completion of certain technical services by MILTENYI to
develop a Cell Separation Kit for VIACELL which is sufficient to deplete [**].

In carrying out the Development Program, MILTENYI and VIACELL shall each use
commercially reasonable efforts to perform such tasks as are set forth to be
performed by it under the terms of this Agreement, in accordance with all
applicable laws, ordinances, rules, regulations, orders, licenses and other
requirements now in effect.

2.2 DEVELOPMENT PROGRAM.

      2.2.1 DEVELOPMENT OF CGMP CELL SEPARATION KIT. MILTENYI will use
commercially reasonable efforts to develop a cGMP Cell Separation Kit for
VIACELL based on MILTENYI Technology.

            (a)   The Parties agree that MILTENYI has already developed the
                  CliniMACS [**] at different fill concentrations from those
                  required for the cell Separation Kit.

            (b)   MILTENYI will develop a CliniMACS [**] and a CliniMACS [**]
                  for use in the Cell Separation Kit, as well as for other uses
                  by MILTENYI.

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            (c)   In developing the Cell Separation Kit, MILTENYI will perform
                  the specific tasks identified in Exhibit A as being the
                  responsibility of MILTENYI and will do so in the manner and to
                  the extent that it has previously done so for developing and
                  filing the Master File for CliniMACS [**]. To the extent that
                  VIACELL requests additional development work, the provisions
                  of Section 2.4 shall apply.

            (d)   For all CliniMACS Reagents used in the Cell Separation Kit,
                  MILTENYI will employ its protein-free manufacturing, FDA
                  accepted virus validation procedure, cell banking and
                  downstream processing experience, including QA and QC
                  experience. To the extent that VIACELL requests additional
                  development work the provisions of Section 2.4 shall apply.

            (e)   MILTENYI will provide VIACELL with sample [**] antibody and
                  [**] antibody to evaluate as soon as it becomes available
                  during the Development Program.

            (f)   VIACELL will use commercially reasonable efforts to provide to
                  MILTENYI initial product requirements for the Cell Separation
                  Kit and MILTENYI and VIACELL, via the Operating Committee,
                  will agree on the Specifications for the Cell Separation Kit
                  in the course of the Development Agreement. To the extent that
                  VIACELL requests additional development work, the provisions
                  of Section 2.4 shall apply.

            (g)   MILTENYI will provide VIACELL with sample Cell Separation Kits
                  in sufficient quantity for VIACELL to evaluate and will
                  provide VIACELL with final Specifications for the Cell
                  Separation Kit, as soon as they become available during the
                  Development Program. [**]. To the extent that VIACELL rejects
                  sample and/or the final Specifications, MILTENYI shall work
                  with VIACELL to develop mutually acceptable specifications
                  and/or MILTENYI shall replace the Cell Separation Kit sample
                  with product that meets such Specifications. To the extent
                  that VIACELL requests additional development work, the
                  provisions of Section 2.4 shall apply.

            (h)   To the extent that VIACELL requests MILTENYI to perform
                  additional work outside the scope of clauses (a) through (g)
                  of this Section 2.2.1, the provisions of Section 2.4 shall
                  apply.

      2.2.2 REGULATORY FILINGS. MILTENYI will prepare and file Master Files with
the FDA for CliniMACS [**] and CliniMACS [**]. MILTENYI will amend the Master
Files for the CliniMACS [**], the CliniMACS [**] and the CliniMACS [**] for the
fill concentrations required for the Cell Separation Kit. The Master Files will
be prepared in accordance with, and with the same type and scope of information
as, the Master File previously submitted by MILTENYI for CliniMACS [**] and
accepted by the FDA. To the extent that VIACELL requests that MILTENYI add
additional information to the Master Files for the CliniMACS Reagents which are
components of the Cell Separation Kit, the provisions of Section 2.4 shall

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apply. MILTENYI shall own and retain all rights, title and interest in and to
all regulatory filings for CliniMACS Reagents, including all Master Files.
Nothing in this Agreement shall give VIACELL the right to view or copy
MILTENYI's Master Files or excerpts of the Master Files.

      2.2.3 UNSPECIFIED TASKS. To the extent the manner of performing or
implementing a task is not specified in Section 2.2.1 or 2.2.2 or in Exhibit A,
the Party who is obligated to perform or implement such task shall have the
right to determine the manner of performance or implementation consistent with
the best interests of the Development Program.

      2.2.4 DEVELOPMENT MILESTONE PAYMENTS. In partial consideration of the
actions undertaken by MILTENYI in connection with the Development Program,
VIACELL will make the following Development Milestone Payments (by wire
transfer) to MILTENYI:

            (a)   [**] on the date of execution of this Agreement; and

            (b)   $250,000.00 (two hundred fifty thousand US dollars) within
                  fifteen (15) after MILTENYI notifies VIACELL that the Master
                  Files for CliniMACS [**] and CliniMACS [**] have been filed
                  with the FDA.

2.3 EXPENSES AND COSTS. Each Party shall bear its own costs and expenses
incurred in the performance of the Development Program except as otherwise
mutually agreed in writing between the Parties hereto.

2.4 COSTS FOR UNSPECIFIED TASKS AND OTHER ADDITIONAL WORK. VIACELL shall pay
MILTENYI at a mutually agreed rate for any work, including technical,
manufacturing, regulatory, QC and QA work, VIACELL requests that is in addition
to the work specifically enumerated in Sections 2.2.1 and 2.2.2.

2.5 DEVELOPMENT PROJECT ADMINISTRATION. Each party will designate one of its
employees to serve as the Project Manager. The Project Manager for a Party may
be changed at any time by the Party and the Party may designate a temporary
substitute at any time. Each Party's Project Manager will be responsible for
coordinating the work performed by the parties to ensure that each Party meets
its obligations under this Agreement. Each Party's Project Manager shall also
serve as the primary contact for the respective designating Party and will be
responsible for maintaining communication between VIACELL and MILTENYL.

      [**]

2.6 MEETINGS. All meetings regarding the Development Program shall take place in
Bergisch Gladbach or Teterow, Germany or another mutually agreed upon location;
provided, however, that the Parties may mutually agree to meet by teleconference
or video conference.

2.7 MILTENYI RIGHTS. MILTENYI and its Affiliates shall have the right to
manufacture, use, sell, offer for sale, sell and import Cell Separation Kits
that are not certified as cGMP Cell Separation Kits. MILTENYI shall also have
the right to manufacture, use, sell, offer for sale, sell and import each of the
components of the Cell Separation Kit, whether they are cGMP or

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non-cGMP. MILTENYI shall further have the right to manufacture, use, sell, offer
for sale and import cGMP Cell Separation Kits that are certified as cGMP Cell
Separation Kits except that MILTENYI may not sell cGMP Cell Separation Kits for
expansion of Hematopoietic stem cells to a competitor of VIACELL without the
prior written permission of VIACELL. In the event VIACELL abandons its efforts
to develop and commercialize a product made using the cGMP Cell Separation Kit,
MILTENYI and its Affiliates shall have the right to manufacture, sell, offer for
sale, use, and sell cGMP Cell Separation Kit, including the right to use cGMP
Cell Separation Kit to manufacture cellular products for cellular therapy.

                    3. TREATMENT OF CONFIDENTIAL INFORMATION

3.1 CONFIDENTIALITY/RESTRICTIONS ON TRANSFER.

      3.1.1 CONFIDENTIAL INFORMATION. MILTENYI and VIACELL each recognize that
the other Party's Confidential Information constitutes highly valuable and
proprietary confidential information. MILTENYI and VIACELL each agree that
during the Term of this Agreement and the term of the Supply Agreement and for
five (5) years after the latter to terminate of those agreements, it will keep
confidential, and will cause its employees, consultants and Affiliates to keep
confidential, and shall not transfer to any Third Party, Confidential
Information of the other Party that is disclosed or transferred to it, or to any
of its employees, consultants and Affiliates, pursuant to or in connection with
this Agreement, without the prior written consent of the other Party and except
to the extent that disclosure, or transfer, is required in accordance with the
performance of this Agreement. Neither VIACELL, nor MILTENYI, nor any of their
respective employees, consultants and Affiliates shall use Confidential
Information of the other Party for any purpose whatsoever except as expressly
permitted in this Agreement. Notwithstanding anything contained herein to the
contrary, the Parties agree that with respect to production technology, QA, QC
and regulation information, such information shall remain confidential without
limit unless such information becomes part of the public domain through no fault
of the recipient of such information.

      3.1.2 NON-DISCLOSURE. Each Party shall take such action, and shall cause
its Affiliates and licensees and sublicensees to take such action, to preserve
the confidentiality of each other's Confidential Information as it would
customarily take to preserve the confidentiality of its own Confidential
Information, and in no event, less than reasonable care. Each Party, upon the
other's request, will return all the Confidential Information disclosed or
transferred to it by the other Party pursuant to this Agreement, including all
copies and extracts of documents and all manifestations in whatever form, within
sixty (60) days of the request following the termination of this Agreement;
provided that a Party may retain Confidential Information of the other Party
relating to any license or right to use Technology which survives such
termination and one copy of all other Confidential Information may be retained
in inactive archives solely for the purpose of establishing the contents
thereof.

3.2 DISCLOSURE REQUIRED BY LAW. If a Party is requested or required by subpoena,
court order, or similar process to disclose any Confidential Information of the
other Party, the parties agree that the Party required or requested to make the
disclosure will provide the other Party with prompt notice of such request(s) so
that the Party whose Confidential Information is required or

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requested to be disclosed may seek appropriate protective order and/or waive the
other Party's compliance with the provisions of Section 3.1.

3.3 EMPLOYEES AND CONSULTANTS. MILTENYI and VIACELL each represent that all of
its employees and the employees of its Affiliates, and any consultants to such
Party or its Affiliates, who shall have access to Confidential Information of
the other Party are bound by written obligations to maintain such information in
confidence and not to use such information except as expressly permitted herein.
Each Party agrees to enforce confidentiality obligations to which its employees
and consultants (and those of its Affiliates) are obligated.

3.4 PUBLICITY. Neither Party may publicly disclose the existence or terms of
this Agreement without the prior written consent of the other Party; provided,
however, that either Party may make such a disclosure to the extent required by
law. Such disclosure shall be on reasonable notice to the other Party and after
taking all reasonable steps to maintain confidentiality. The Parties, upon the
execution of this Agreement, will jointly prepare a press release and will
jointly decide about an appropriate time for publishing such press release. The
Parties agree that there will be no press release related to this Agreement or
the Supply Agreement that is not authorized by all Parties. Once any written
statement is approved for disclosure by the other Party, either Party may make
subsequent public disclosure of the contents of such statement without the
further approval of the other Party.

3.5 LIMITATION ON DISCLOSURES. Notwithstanding any provision in this Agreement,
neither Party shall be obligated hereunder to disclose to the other Party any
information which it is prohibited from disclosing by law or under any agreement
with a Third Party.

3.6 THIS AGREEMENT. The Parties agree that the material terms of this Agreement
shall be considered Confidential Information of each of the Parties. The Parties
will consult with one another and agree on the provisions of the Agreement to be
redacted in any filings made by any Party with the Securities and Exchange
Commission or as otherwise required by law or regulation. Notwithstanding the
foregoing, each Party shall have the right to disclose in confidence the
material terms of this Agreement to parties retained by such Party to perform
legal, accounting or similar services and who have a need to know such terms in
order to provide such services and to other parties upon the prior written
approval of the Parties to this Agreement.

                        4. INTELLECTUAL PROPERTY RIGHTS

4.1 OWNERSHIP.

      4.1.1 MILTENYI INTELLECTUAL PROPERTY RIGHTS. Except as otherwise provided
herein, MILTENYI shall have sole and exclusive ownership of all right, title and
interest on a worldwide basis in and to any and all MILTENYI Technology with
full rights to license or sublicense. Without limiting the foregoing, except as
otherwise provided herein, MILTENYI shall be the sole owner of all Patent
Rights, all trade secret rights, all know-how and any other intellectual
property rights in the MILTENYI Technology including the sole and exclusive
right to exclude others from making, using, selling, offering for sale or
importing the MILTENYI Technology or any products derived from any MILTENYI
Technology.

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      4.1.2 VIACELL INTELLECTUAL PROPERTY RIGHTS. VIACELL shall have sole and
exclusive ownership of all right, title and interest on a worldwide basis in and
to any and all VIACELL Technology with full rights to license or sublicense
except as provided for in Section 2.7. Without limiting the foregoing, VIACELL
shall be the sole owner of all Patent Rights, all trade secret rights, all
know-how and any other intellectual property rights in the VIACELL Technology,
including the sole and exclusive right to exclude others from making, using,
selling, offering for sale or importing the VIACELL Technology or any products
derived from any VIACELL Technology.

      4.1.3 JOINT TECHNOLOGY. MILTENYI and VIACELL shall each own an undivided
interest in all Joint Technology, which is defined for purposes of this
Agreement as Technology (i) jointly invented, discovered, acquired, or developed
by or on behalf of both VIACELL (and/or any party performing sponsored research
for VIACELL) and MILTENYI (and/or any party performing sponsored research for
MILTENYI) or (ii) invented, discovered or developed by one Party (or during any
research sponsored by such party) with the use of the Technology of the other
Party.

4.2 INVENTORSHIP. In case of a dispute between MILTENYI or VIACELL over
inventorship, the Chief Executive Officers of the Parties or their designee(s),
shall make the determination of the inventor(s) by application of the standards
contained in United States patent law. The Chief Executive Officers of the
Parties or their designee(s), shall also, in the case of dispute, make the
determination as to whether an invention is Joint Technology. All such
determinations shall be treated as Joint Decisions hereunder. If the Chief
Executive Officers of the Parties or their designee(s) cannot resolve the
dispute, it shall be resolved by independent patent counsel, not otherwise
engaged by either of the Parties, selected by the Chief Executive Officers of
the Parties or their designee(s). Expenses of such independent patent counsel
shall be shared equally by the Parties.

             5. FILING, PROSECUTION AND MAINTENANCE OF PATENT RIGHTS

5.1 FILING OF PATENTS. Each Party will be responsible for the filing and
prosecution, in such countries as the responsible Party shall select, of patents
on Technology solely owned or solely invented by such Party and on Joint
Technology which principally relates to its own Techno logy and which is
developed during the Development Program, provided that the other Party will
have the opportunity to provide substantive review and comment on any such
prosecution solely as it relates to claims in the scope of the Development
Program. Portions of any documents relating to any such prosecution not within
the scope of the Development Program may be redacted by a Party prior to
provision to the other Party. Except as set forth above, responsibility for
filing and prosecution of patents on Joint Technology not principally related to
either VIACELL Technology alone or MILTENYI Technology alone will be determined
by the Chief Executive Officers or their designee(s) on a case-by-case basis and
handled by mutually acceptable patent counsel charged with the duty to act in
the best interests of the Development Program.

5.2 EXPENSES. MILTENYI shall bear the cost for the filing, prosecution and
maintenance of MILTENYI Patent Rights. VIACELL shall bear the cost for the
filing, prosecution and maintenance of VIACELL Patent Rights. The parties shall
share equally the cost for the filing, prosecution and maintenance of Joint
Patent Rights, and in the event either Party uses any

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in-house patent counsel, expenses shall be shared in such instance based on
reasonable rates as agreed in advance by the Chief Executive Officers or their
designee(s).

5.3 Legal Action.

      5.3.1 ACTUAL OR THREATENED INFRINGEMENT. Subject to any obligation to a
Third Party licensor of Technology or Patent Rights to a Party with respect to
the subject matter hereof:

            (a)   In the event either Parties becomes aware of any possible
                  infringement or unauthorized possession, knowledge or use of
                  any intellectual property which is the subject matter of this
                  Agreement (collectively, an "Infringement"), that Party shall
                  promptly notify the other Party and provide it with full
                  details. Upon a determination by either Party that such
                  Infringement involves the manufacture, use, sale, offer for
                  sale, or import of Cell Separation Kits by a Third Party, such
                  Party may give notice of such determination to the other Party
                  hereto (an "Infringement Notice"). If such infringement
                  relates solely to the infringement of MILTENYI patent rights,
                  then MILTENYI shall have the option, but not the obligation,
                  to prosecute or prevent the Infringement of Patent Rights
                  relating to the Cell Separation Kits or the manufacture or use
                  thereof. If such infringement relates solely to the
                  infringement of VIACELL patent rights, then VIACELL shall have
                  the option, but not the obligation, to prosecute or prevent
                  the Infringement of Patent Rights relating to the Cell
                  Separation Kits or the manufacture, use, offer for sale or
                  import thereof. If either Party determines that it is
                  necessary or desirable for the other to join any such suit,
                  action or proceeding, the second Party shall execute all
                  papers and perform such other acts as may be reasonably
                  required in the circumstances. In the event of an Infringement
                  of a Joint Patent Right, or in the event such infringement
                  does not relate solely to MILTENYI patent rights or VIACELL
                  patent rights, the Chief Executive Officers or their
                  designee(s) shall determine whether and how to prosecute or
                  prevent the Infringement. If the Chief Executive Officers are
                  unable to determine whether and how to commence an action for
                  infringement of a Joint Patent Right, either Party shall have
                  the right to prosecute such patent infringement action. The
                  Party bringing any action under this Section 5.3.1(a) shall do
                  so at its own expense and shall retain all amounts received as
                  a result of such action.

            (c)   In any action under Section 5.3.1, the Parties shall fully
                  cooperate with and assist each other.

            (d)   In the event that the scope of an action under Section 5.3.1
                  goes beyond the scope of the Development Program and an award
                  of damages or royalties is granted for infringing activity
                  outside the scope of the Development Program, such award shall
                  be retained by the owner of the Patent Right in question.

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5.4 DEFENSE OF CLAIMS. Subject to any obligation to a Third Party licensor of
Technology or Patent Rights to a Party with respect to the subject matter
hereof, in the event that any action, suit or proceeding is brought against
MILTENYI or VIACELL or any Affiliate of either Party alleging the infringement
of the intellectual property rights of a Third Party by reason of the discovery,
development, manufacture, use, sale, importation or offer for sale of Cell
Separation Kits or use of MILTENYI, VIACELL or Joint Technology in the
discovery, development, manufacture, use, sale, offer for sale, or importation
of Cell Separation Kits, the Parties will cooperate with each other in the
defense of any such suit, action or proceeding. The Parties will give each other
prompt written notice of the commencement of any such suit, action or proceeding
or claim of infringement. Neither Party shall compromise, litigate, settle or
otherwise dispose of any such suit, action or proceeding which involves the use
of the other's Technology or Patent Rights without the other Party's advice and
prior consent, provided that the Party not defending the suit shall not
unreasonably withhold its consent to any settlement which does not have a
material adverse effect on its business. If the defending Party agrees that the
other Party should institute or join any suit, action or proceeding pursuant to
this Section, the other Party may at its expense, join the defending Party as a
party to the suit, action or proceeding, and the Party so joined shall execute
all documents and take all other actions, including giving testimony, which may
reasonably be required in connection with the prosecution of such suit, action
or proceeding. To the extent that the allegation of infringement is based
principally on the use of VIACELL Technology, or on the manufacture, use, sale,
offer for sale or import of Cell Separation Kits, and no other MILTENYI products
or MILTENYI processes used to produce other MILTENYI products are accused of
infringement, VIACELL shall have the right to join in any suit, action,
proceeding pursuant to this Section alleging the infringement of the
intellectual property rights of a Third Party by reason of the discovery,
development, manufacture, use, sale, importation or offer for sale of Cell
Separation Kits or use of VIACELL Technology in the discovery, development,
manufacture, use, sale, offer for sale, or importation of Cell Separation Kits
and the expenses of defense of the suit shall be borne by VIACELL. To the extent
that the allegation of infringement is based principally on the use of MILTENYI
Technology, or on the manufacture, use, sale, offer for sale or import of the
Cell Separation Kits, and no other VIACELL products or VIACELL processes used to
produce other VIACELL products are accused of infringement, MILTENYI shall have
the right to join in any suit, action, proceeding pursuant to this Section
alleging the infringement of the intellectual property rights of a Third Party
by reason of the discovery, development, manufacture, use, sale, importation or
offer for sale of Cell Separation Kits or use of MILTENYI Technology in the
discovery, development, manufacture, use, sale, offer for sale, or importation
of Cell Separation Kits. To the extent that the allegation of infringement is
based principally on the use of Joint Technology, or to the extent that the
allegation of infringement is not based principally on the use of either
MILTENYI Technology or VIACELL Technology, each Party shall have the right to
join in any suit, action, proceeding pursuant to this Section alleging the
infringement of the intellectual property rights of a Third Party by reason of
the discovery, development, manufacture, use, sale, importation or offer for
sale of Cell Separation Kits or use of Joint Technology in the discovery,
development, manufacture, use, sale, offer for sale, or importation of Cell
Separation Kits. The Parties shall bear their own expenses in defense of the
suit. If as a consequence of such action, suit or proceeding by a Third Party
claiming that the discovery, development, manufacture, use or sale of a Cell
Separation Kit infringes such Third Party's intellectual property rights, the
Parties shall examine and discuss in good faith the consequences

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of such prohibition or restriction or other conditions on this agreement and on
possible modification thereto.

                        6. TERMINATION AND DISENGAGEMENT

6.1 TERM. This Agreement shall commence on the Effective Date and, unless sooner
terminate as provided herein, shall continue in effect until the earlier of (i)
the expiration of all of the payment obligations of VIACELL under the Agreement
and all of the development obligation of MILTENYI under the Agreement and (ii)
two (2) years from the Effective Date.

6.2 TERMINATION.

      6.2.1 TERMINATION FOR CAUSE. The Agreement may be terminated at any time
by either Party in the following ways:

            (a)   immediately by a Party if (i) the other Party shall have
                  dissolved, ceased active business operations or liquidated,
                  unless such dissolution, cessation or liquidation results from
                  reorganization, acquisition, merger or similar event, or (ii)
                  bankruptcy or insolvency proceedings, including any proceeding
                  under Title 11 of the United States Code, have been brought by
                  or against the other Party and, in the event such a proceeding
                  has been brought against such Party, remains undismissed for a
                  period of sixty (60) days, or (iii) an assignment has been
                  made for the benefit of the other Party's creditors or a
                  receiver of such Party's assets has been appointed; or

            (b)   by the non-defaulting Party upon thirty (30) days written
                  notice to the defaulting Party (which notice shall specify the
                  nature of the default), if either Party shall have failed in
                  the full and timely observance or performance of any of its
                  obligations under this Agreement, including, without
                  limitation, the failure by either Party to meet its
                  obligations set forth in the Development Program in a timely
                  manner.

6.3 CONSEQUENCES OF TERMINATION OR EXPIRATION

      6.3.1 TECHNOLOGY RIGHTS. Except as otherwise provided in Section 2.7, in
the event of termination of the Development Program

            (a)   each Party will retain exclusive rights under its own
                  Technology and Patent Rights, and each Party shall be free to
                  pursue the development and commercialization of such rights in
                  any manner that it may choose, subject only to the rights as
                  set forth below; and

            (b)   all exclusive and non-exclusive rights granted to either Party
                  shall immediately terminate.

      6.3.2 RIGHT TO DEVELOPMENT MILESTONE PAYMENTS. If VIACELL terminates this
Agreement for any reason other than pursuant to Section 6.2.1(b) or if MILTENYI
terminates this Agreement terminates pursuant to Section 6.2.1 and any of the
Development Milestone

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Payments have not been paid to MILTENYI, the unpaid Development Milestone
Payments shall be paid to MILTENYI within fifteen (15) days by wire transfer.

6.4 SURVIVING PROVISIONS. Termination and expiration of this Agreement for any
reason shall be without prejudice to:

            (a)   the rights and obligations of the Parties provided in 2.2.4,
                  2.3, 6.3, 10.1, 10.2, 10.3, 10.4, 10.5, 10.7, 10.8, 10.9,
                  10.10, 10.11, 10.12 and Articles 3, 4, 5, 7, 8, 9 and 1 (to
                  the extent terms defined therein are used in other surviving
                  sections or articles hereof) all of which shall survive such
                  termination;

            (b)   any rights of either Party which may have accrued up to the
                  date of such termination or expiration; and

            (c)   any other rights or remedies provided at law or equity which
                  either Party may otherwise have against the other.

                       7. REPRESENTATIONS AND WARRANTIES

7.1 MUTUAL REPRESENTATIONS. MILTENYI and VIACELL each represents and warrants to
the other, as of the Effective Date as follows:

      7.1.1 ORGANIZATION. It is a corporation duly organized, validly existing
and in good standing under the laws of the jurisdiction of its incorporation, it
is qualified to do business and is in good standing as a foreign corporation in
each jurisdiction in which the performance of its obligations hereunder requires
such qualification and has all requisite power and authority, corporate or
otherwise, to conduct its business as now being conducted, to own, lease and
operate its properties and to execute, deliver and perform this Agreement.

      7.1.2 AUTHORIZATION. The execution, delivery and performance by it of this
Agreement have been duly authorized by all necessary corporate action and do not
and will not (a) require any consent or approval of its stockholders or (b)
violate any provision of any agreement, law, rule, regulation, order, writ,
judgment, injunction, decree, determination or award presently in effect having
applicability to it or any provision of its charter documents.

      7.1.3 BINDING AGREEMENT. This Agreement is a legal, valid and binding
obligation of it, enforceable against it in accordance with its terms and
conditions.

      7.1.4 NO INCONSISTENT OBLIGATION. It is not under any obligation to any
person, or entity, contractual or otherwise, that is conflicting or inconsistent
in any respect with the terms of this Agreement or that would impede the
diligent and complete fulfillment of its obligations hereunder and that it has
all power and authority under all instruments or agreements to which it is a
party to enter into this Agreement and to perform its obligations hereunder.
Furthermore, except as otherwise provided herein, it is not a party to any
agreement that would directly or indirectly grant rights in the other Party's
Technology to any Third Party.

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                               8. INDEMNIFICATION

8.1 INDEMNIFICATION OF VIACELL BY MILTENYI. MILTENYI shall indemnify, defend and
hold harmless VIACELL, its Affiliates and their respective directors, officers,
employees, and agents and their respective successors, heirs and assigns (the
"VIACELL Indemnitees"), against any liability, damage, loss or expense
(including reasonable attorneys' fees and expenses of litigation) incurred by or
imposed upon the VIACELL Indemnities, or any one of them, in connection with any
claims, suits, actions, demands or judgments of any Third Party (except in cases
where such claims, suits, actions, demands or judgments result from a material
breach of this Agreement, gross negligence or willful misconduct on the part of
VIACELL) arising out or based on the breach by MILTENYI of any of its
representations, warranties, covenants or obligations contained or incorporated
in this Agreement or willful misconduct except that MILTLENYI shall not
indemnify VIACELL for any liability, damage, loss or expense (including
reasonable attorneys' fees and expenses of litigation) incurred by or imposed
upon the VIACELL Indemnities, or any one of them, in connection with any claims,
suits, actions, demands or judgments of any Third Party for patent infringement
or for any product liability claims (unless in cases of willful misconduct). IN
NO EVENT WILL MILTENYI BE LIABLE FOR ANY CONSEQUENTIAL, INDIRECT OR EXEMPLARY
DAMAGES SUFFERED BY THE VIACELL INDEMNITEES.

8.2 INDEMNIFICATION OF MILTENYI BY VIACELL. VIACELL shall indemnify, defend and
hold harmless MILTENYI, its Affiliates and their respective directors, officers,
employees and agents and their respective successors, heirs and assigns (the
"MILTENYI Indemnitees"), against any liability, damage, loss or expense
(including reasonable attorneys' fees and expenses of litigation) incurred by or
imposed upon the MILTENYI Indemnitees, or any one of them, in connection with
any claims, suits, actions, demands or judgments of any Third Party (except in
cases where such claims, suits, actions, demands or judgments result from
willful misconduct on the part of MILTENYI) arising out or based on product
liability, patent infringement or the breach by VIACELL of any of its
representations, warranties, covenants or obligations contained or incorporated
in this Agreement. IN NO EVENT WILL VIACELL BE LIABLE FOR ANY CONSEQUENTIAL,
INDIRECT OR EXEMPLARY DAMAGES SUFFERED BY THE MILTENYI INDEMNITEES.

8.3 INDEMNITY PROCEDURE. In the event that a Party is seeking indemnification
under Section 8.1 or 8.2, it shall inform the other Party (the "Indemnifying
Party") of a claim as soon as reasonably practicable after it receives notice of
the claim, shall permit the Indemnifying Party to assume direction and control
of the defense of the claim (including the right to settle the claim solely for
monetary consideration), and, at the Indemnifying Party's expense, shall
cooperate as reasonably requested in the defense of the claim. The Indemnified
Party shall have the right to retain its own counsel, subject to the approval of
any such outside counsel by the Indemnifying Party, with the fees and expenses
to be paid by the Indemnifying Party if representation of such Party by the
counsel retained by Indemnifying Party would be inappropriate due to actual or
potential differing interests between such indemnitee and any other Party
represented by such counsel in such proceedings. The Indemnifying Party may not
settle such action or claim, or otherwise consent to an adverse judgment in such
action or claim, without the express written consent of the Indemnified Party if
such settlement or adverse judgment diminishes the rights or interests of the
Indemnified Party but such written consent shall not be unreasonably withheld.

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8.4 LIMITATION OF MILTENYI'S LIABILITY. MILTENYI's liability is limited to
developing a Cell Separation Kit meeting the mutually agreed upon
Specifications. MILTENYI is in no event liable for any damage, loss or expense
arising out or based on any use of the Cell Separation Kit or cGMP Cell
Separation Kit by VIACELL, unless in cases of willful misconduct. Any and all
claims of VIACELL, against MILTENYI for any other reasons than willful
misconduct or failure of MILTENYI to develop a Cell Separation Kit or cGMP Cell
Separation Kit not meeting the mutually agreed upon Specifications are excluded.
VIACELL is aware that this provision may require the consent of VIACELL's
insurance company providing pharmaceutical liability insurance. VIACELL shall
provide such consent in writing to MILTENYI.

8.5 FURTHER LIMITATION OF LIABILITY. In any event, MILTENYI's liability for any
claim and obligation to indemnify VIACELL or its Affiliates shall be limited to
the aggregate amount of all payments received by Miltenyi under this Agreement
from VIACELL.

8.6 WARRANTY DISCLAIMER. EXCEPT AS OTHERWISE EXPRESSLY PROVIDED IN THIS
AGREEMENT, NEITHER PARTY MAKES ANY WARRANTY WITH RESPECT TO ANY TECHNOLOGY,
GOODS, SERVICES, RIGHTS OR OTHER SUBJECT MATTER OF THIS AGREEMENT AND HEREBY
DISCLAIMS WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT WITH RESPECT TO ANY AND ALL OF THE FOREGOING.

8.7 LIMITED LIABILITY. NOTWITHSTANDING ANYTHING ELSE IN THIS AGREEMENT OR
OTHERWISE, NEITHER VIACELL NOR MILTENYI WILL BE LIABLE WITH RESPECT TO ANY
SUBJECT MATTER OF THIS AGREEMENT UNDER ANY CONTRACT, NEGLIGENCE, STRICT
LIABILITY OR OTHER LEGAL OR EQUITABLE THEORY FOR (I) ANY INDIRECT, INCIDENTAL,
CONSEQUENTIAL OR PUNITIVE DAMAGES OR LOST PROFITS OR (II) COST OF PROCUREMENT OF
SUBSTITUTE GOODS, TECHNOLOGY OR SERVICES.

                             9. DISPUTE RESOLUTION

9.1 DISPUTE RESOLUTION.

      9.1.1 GENERAL. In the event of any dispute, difference or question arising
between the Parties in connection with this Agreement, the construction thereof,
or the rights, duties or liabilities of either Party, and which dispute cannot
be amicably resolved by the good faith efforts, then such dispute shall be
resolved by binding arbitration as set forth in Section 9.1.2.

      9.1.2 ARBITRATION. Binding arbitration shall be conducted in accordance
with the Arbitration Rules of the Cologne Chamber of Commerce and Industry (IHK
Koln) without recourse to the ordinary courts of law. The arbitration panel
shall be composed of three arbitrators, one of whom shall be chosen by MILTENYI,
one by VIACELL and the third, who shall be chairman of the panel, by the two so
chosen. If both or either of MILTENYI or VIACELL fails to choose an arbitrator
or arbitrators within fourteen (14) days after receiving notice of commencement
of arbitration or if the two arbitrators fail to choose a third arbitrator
within fourteen (14) days after their appointment, the then President of the
Cologne Chamber of Commerce and Industry shall, upon the request of both or
either of the Parties to the arbitration,

                                      -15-
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appoint the arbitrator or arbitrators required to complete the board or, if he
shall decline or fail to do so, such arbitrator or arbitrators shall be
appointed by the Cologne Chamber of Commerce and Industry.

            (a)   EXCHANGE OF PROPOSALS. Within ten (10) days of the appointment
                  of the full arbitration panel, the Parties shall exchange
                  documents setting forth their final detailed proposals for
                  resolution of the matter in dispute, together with a brief or
                  other written memorandum supporting the merits of their final
                  proposal. The arbitration panel shall promptly convene a
                  hearing, at which time each Party shall have an agreed upon
                  time to argue and present witnesses in support of its final
                  proposal.

            (b)   GOVERNING LAW. In the event the arbitrators seek the guidance
                  of the law of any jurisdiction, the laws of Germany shall
                  govern.

            (c)   LANGUAGE. The language of the proceedings shall be English.

            (d)   NOTIFICATION OF DECISION. The arbitrators shall make their
                  decision known to both Parties as quickly as possible by
                  delivering written notice of their decision to both Parties.
                  The Parties shall agree in writing to comply with the proposal
                  selected by the arbitration panel within five (5) days of
                  receipt of notice of such selection. The decision of the
                  arbitrators shall be final and binding on the Parties, and
                  specific performance may be ordered by any court of competent
                  jurisdiction.

            (e)   COSTS. The Parties shall bear their own costs in preparing for
                  the arbitration. The costs of the arbitrators shall be equally
                  divided between the Parties.

                               10. MISCELLANEOUS

10.1 NOTICES.

All notices under this Agreement shall be in writing mailed via certified mail,
return receipt requested, courier, or facsimile transmission addressed as
follows, or to such other address as may be designated from time to time:

            If to MILTENYI:  Miltenyi Biotec GmbH
                             Friedrich-Ebert-Str. 68
                             D-51429 Bergisch Gladbach
                             Germany
                             Attn: Stefan Miltenyi
                             FAX: +49 2204 85197

            With a copy to:  Miltenyi Biotec GmbH
                             Friedrich-Ebert-Str. 68
                             D-51429 Bergisch Gladbach
                             Germany

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                             Attn: General Counsel
                             Fax: +49 2204 85197

             If to VIACELL:  ViaCell, Inc.
                             245 First Street, Fifteenth Floor
                             Cambridge, MA 02142
                             Attn: Marc Beer
                             Fax: +1 617 914 3855

            With a copy to:  Ropes & Gray
                             One International Place
                             Boston, MA 02110
                             USA
                             Attn: Marc Rubenstein
                             Fax: +1 617 951-7050

      Notices shall be deemed given as of the date received. If facsimile
transmission is used, an additional means of notification shall be used,
however, notice shall be deemed to be given as of the date the facsimile
transmission was received.

10.2 GOVERNING LAW AND JURISDICTION. This Agreement shall be governed by and
construed in accordance with the laws of Germany, without regard to the
application of principles of conflicts of law.

10.3 BINDING EFFECT. Except as provided for in Section 10.14, as of the
Effective Date, this Agreement shall be binding upon and inure to the benefit of
the Parties and their respective legal representatives, successors and permitted
assigns.

10.4 HEADINGS. Section and subsection headings are inserted for convenience of
reference only and do not form a part of this Agreement.

10.5 COUNTERPARTS. This Agreement may be executed simultaneously in two or more
counterparts, each of which shall be deemed an original.

10.6 AMENDMENT; WAIVER. This Agreement may be amended, modified, superseded or
canceled, and any of the terms may be waived, only by a written instrument
executed by each Party or, in the case of waiver, by the Party or Parties
waiving compliance. The delay or failure of any Party at any time or times to
require performance of any provisions shall in no manner affect the rights at a
later time to enforce the same. No waiver by any Party of any condition or of
the breach of any term contained in this Agreement, whether by conduct, or
otherwise, in any one or more instances, shall be deemed to be, or considered
as, a further or continuing waiver of any such condition or of the breach of
such term or any other term of this Agreement.

10.7 NO THIRD PARTY BENEFICIARIES. Except as set forth in Sections 8.1 and 8.2
hereof, no Third Party, including any employee of any Party to this Agreement,
shall have or acquire any rights by reason of this Agreement.

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10.8 ASSIGNMENT. Neither this Agreement nor any obligation of a party hereunder
may be assigned by either Party without the consent of the other, except that
each Party may assign this Agreement and the rights, obligations and interests
of such Party, in whole or in part, to any of its Affiliates.

10.9 FORCE MAJEURE. Neither MILTENYI or VIACELL shall be liable for failure of
or delay in performing obligations set forth in this Agreement, and neither
shall be deemed in breach of its obligations, if such failure or delay is due to
natural disasters or any causes beyond the reasonable control of MILTENYI or
VIACELL. In event of such force majeure, the Party affected thereby shall use
reasonable efforts to cure or overcome the same and resume performance of its
obligations thereunder.

10.10 INTERPRETATION. The Parties hereto acknowledge and agree that : (i) each
Party and its counsel reviewed and negotiated the terms and provisions of this
Agreement and have contributed to its revision; (ii) the rule of construction to
the effect that any ambiguities are resolved against the drafting Party shall
not be employed in the interpretation of this Agreement; and (iii) the terms and
provisions of this Agreement shall be construed fairly as to all Parties hereto
and not in a favor of or against any Party, regardless of which Party was
generally responsible for the preparation of this Agreement.

10.11 INTEGRATION: SEVERABILITY. This Agreement is the sole agreement with
respect to the subject matter hereof and supersedes all other agreements and
understandings between the Parties with respect to same. If any provision of
this Agreement is or becomes invalid or is ruled invalid by any court of
competent jurisdiction or is deemed unenforceable, it is the intention of the
Parties that the remainder of the Agreement shall not be affected.

10.12 RELATIONSHIP OF THE PARTIES. Each of the Parties shall be independent
contractors with respect to each other, and the relationship established hereby
shall not constitute a partnership, joint venture, or agency. No Party shall
have the authority to make statements, representations or commitments of any
kind, or take any action, which shall be binding on any other Party, without the
express, prior, written consent of the Party to be so bound.

10.13 FURTHER ASSURANCES. Each of MILTENYI and VIACELL agrees to duly execute
and deliver, or cause to be duly executed and delivered, such further
instruments and do and cause to be done such further acts and things, including
without limitation, the filing of such additional assignments, agreements,
documents and instruments, that may be necessary or as the other Party hereto
may at any time and from time to time reasonably request in connection with this
Agreement or to carry out more effectively the provisions and purposes of, or to
better assure and confirm unto such other Party its rights and remedies under,
this Agreement.

10.14 SIMULTANEOUS EXECUTION OF THE AGREEMENT AND THE SUPPLY AGREEMENT. The
Parties agree that they will execute and they will execute this Agreement
simultaneously with the Supply Agreement and neither the Agreement nor the
Supply Agreement shall become binding on any Party unless the Agreement and the
Supply Agreement are executed by all parties to those Agreements.

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      IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed
by their duly authorized representatives.

MILTENYI BIOTEC GMBH

By: /s/ Stefan Miltenyi
    _______________________
Name: Stefan Miltenyi
Title: Geschaftsfuhrer

Date: ______________________

VIACELL, INC.

By: /s/ Marc Beer
    _______________________
Name: Marc Beer
Title: Chief Executive Officer

Date: ______________________

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                                    EXHIBIT A

[**]

                                      -20-