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                                                                    Exhibit 10.4

                    AMENDED AND RESTATED EMPLOYMENT AGREEMENT

     THIS EMPLOYMENT AGREEMENT dated as of March 12, 2007 (the "Agreement"), is
between ViaCell, Inc. (the "Company"), a Delaware corporation, with its
principal place of business at One Innovation Drive, Worcester, Massachusetts
01605 and Morey Kraus (the "Executive").

     WHEREAS, the Executive and the Company are parties to a certain Employment
Agreement dated April 11, 2000 (the "Previous Agreement") pursuant to which the
Executive has been serving the Company as its Chief Technology Officer; and

     WHEREAS, the Company and the Executive desire to make certain changes to
the terms and conditions of the Executive's employment;

     NOW, THEREFORE, in consideration of the mutual covenants and promises
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the parties hereby agree as
follows:

     1. Employment; Title and Duties; Extent of Services. Upon the terms and
subject to the conditions set forth in this Agreement, the Company hereby
employs the Executive, and the Executive hereby accepts employment with the
Company, to serve as Chief Technology Officer of the Company and to perform such
specific duties as may reasonably be assigned to the Executive from time to time
by the Board of Directors of the Company (the "Board"). The Executive agrees to
serve in such capacity, and to devote his best efforts and full working time,
attention and energy to the performance of such duties until the termination of
his employment under this Agreement. The Executive shall report to the Chief
Executive Officer of the Company.

     2. Term of Employment. The Company agrees to employ the Executive, and the
Executive agrees to serve the Company, for a period commencing on January 1,
2007 and continuing through the period ending one (l) year following such date
(the "Initial Employment Period") unless Executive's employment is earlier
terminated pursuant to the terms of Section 4. At the end of the Initial
Employment Period (and any renewal period provided for herein), this Agreement
shall automatically be extended for additional one year periods (the "Renewal
Period"), unless either party hereto gives a written notice of non-renewal
delivered not less than three (3) months prior to the end of the Initial
Employment Period or any Renewal Period.

     3. Compensation and Benefits.

     3.1. Base Salary. For the period from the Effective Date until December 31,
2007, the Company shall pay to the Executive a base Salary of $237,405 per year
(the "Base Salary"), payable in substantially equal biweekly installments or in
accordance with the Company's regular payroll practices as in effect from time
to time. For the 2008 fiscal year and thereafter, the Executive's Base Salary
shall be subject to adjustment, as determined by mutual agreement between the
Board and the Executive.

     3.2. Bonus. In addition to the Base Salary, the Executive shall participate
in the Company's incentive compensation programs for senior executive officers
existing from time to

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time, including, without limitation, a performance bonus program pursuant to
which the Executive shall be entitled to receive an annual incentive based award
(the "Performance Bonus") based on the achievement of certain performance
milestones to be mutually agreed upon by the Board and the Executive for the
relevant fiscal year. In determining whether the Executive has achieved the
annual performance milestones for any fiscal year under any of the Company's
incentive compensation programs or otherwise in respect of the Performance
Bonus, extraordinary, nonrecurring non-cash items of income and expense shall be
disregarded.

     3.3. Stock Options. All options to purchase securities of the Company
previously granted to the Executive shall continue to be subject to all of the
terms and conditions on which they were granted, except as provided herein.

     3.4. Fringe Benefits. During the term of the Executive's employment
hereunder, the Executive shall be entitled to participate in all special benefit
or perquisite programs and employee benefit plans and programs of the Company
established or made available to its senior executive officers (including,
without limitation, any health, dental, short and long-term disability, group
term and supplemental life insurance, accidental death and dismemberment,
savings and retirement plans). The Executive shall be entitled to receive
benefits no less favorable than those provided to other senior executives of the
Company.

     3.5. Vacation. The Executive shall be entitled to the number of days of
paid vacation per calendar year customarily provided by the Company to its
senior executive officers and consistent with the Company's vacation policy, as
in effect from time to time.

     3.6. Reimbursement of Expenses. The Company shall reimburse the Executive
for reasonable expenses incurred in connection with his employment by the
Company, including, without limitation, reasonable travel, lodging and meal
expenses incurred by him in connection with his performance of services
hereunder, upon submission of supporting documentation reasonably satisfactory
to the Company.

     4. Termination.

     4.1. The Executive's employment hereunder may be terminated by the Company
under the following circumstances:

          (a) Death. Immediately upon the death of the Executive.

          (b) Disability. At any time, as a result of the Executive's incapacity
due to physical or mental illness resulting in a Disability of the Executive.
For purposes of this Agreement "Disability" shall mean the inability of the
Executive (either with or without reasonable accommodation) to substantially
perform the services contemplated under this Agreement for a period of 90
consecutive calendar days or more within any six month period during the Initial
Employment Term or any Renewal Period, as determined by a physician satisfactory
to both the Executive and the Company; provided, that if the Executive and the
Company do not agree on a physician, the Executive and the Company shall each
select a physician who shall together select a third physician whose
determination as to disability shall be binding on both parties.


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          (c) For Cause. For purposes of this Agreement, the Company shall have
"Cause" to terminate the Executive's employment hereunder in the event that:

               (1) the Executive shall have willfully failed and continued to
fail substantially to perform the duties (other than any failure resulting from
the Executive's Disability or any actual or anticipated failure under the
issuance by him of a Notice of Termination, as defined in Section 4.4), for
thirty (30) days after a written demand for performance is delivered to the
Executive on behalf of the Company which specifically identifies the manner in
which it is alleged that the Executive has not substantially performed his
duties; or

               (2) the Executive shall have engaged in (i) any material
misappropriation of funds, properties or assets of the Company, it being
understood that "material" for these purposes shall take into account both the
amount of funds, properties or assets misappropriated and the circumstances
thereof (including the intent of the Executive in connection therewith) or (ii)
any malicious damage or destruction of any property or assets of the Company,
whether resulting from the Executive's willful actions or omissions or the
Executive's gross negligence;

               (3) the Executive shall have been convicted of a crime involving
moral turpitude or constituting a felony; or

               (4) the Executive shall have materially breached his obligations
under this Agreement or the Non-Competition/Assignment of Inventions Agreement
between the Company and the Executive dated as of the date hereof (the
"Non-Competition Agreement"), and such breach shall remain uncured by the
Executive for thirty (30) days following receipt of notice from the Company
specifying such breach.

          (d) Without Cause. The Company may terminate (by majority vote of the
Board) the Executive's employment hereunder without Cause, upon sixty (60) days
prior written notice.

     4.2. The Executive may terminate his employment hereunder for "Reason" in
the event the Company breaches any material provision of this Agreement and such
breach remains uncured by the Company after 30 days following receipt of notice
from the Executive specifying such breach. For purposes of this Agreement, the
Company shall be in breach of a material provision of this Agreement in the
event that, without the express written consent of the Executive, it: (a) fails
to pay the Executive his compensation and/or benefits as provided in Section 3;
(b) makes any material change to the Company's 1998 Equity Incentive Plan that
would adversely affect the options granted under the Previous Agreement; (c)
assigns the Executive duties inconsistent with the Executive's title, position,
duties, and responsibilities, as provided in Section 1, which results in a
material diminution in such position and duties (excluding for this purpose an
isolated, insubstantial and inadvertent action not taken in bad faith which is
remedied by the Company promptly after notice by the Executive hereof); (d)
requires the Executive to relocate a distance of more than 60 miles from
Harvard, Massachusetts; or (e) fails to secure the assumption of this Employment
Agreement by any acquirer or any corporation with which or into which the
Company may be merged or which may succeed to its assets or business.


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     4.3. Termination by the Executive without Reason. The Executive may
terminate his employment hereunder without Reason, upon sixty (60) days prior
written notice.

     4.4. Notice of Termination. Any termination of the Executive's employment
by the Company or by the Executive (other than termination pursuant to Section
4.1) shall be communicated by Notice of Termination to the other party hereto.
For purposes of this Agreement, a "Notice of Termination" shall mean a written
notice which shall indicate the specific termination provision in this Agreement
relied upon and shall set forth in reasonable detail the facts and circumstance
which provide a basis for termination of the Executive's employment under the
provision so indicated.

     4.5. Date of Termination. "Date of Termination" shall mean (i) if the
Executive's employment is terminated pursuant to Section 4.1(a) the date of the
Executive's death, (ii) if the Executive's employment is terminated pursuant to
Section 4.1(b), 30 days after the Notice of Termination is given (provided that
the Executive shall not have returned to the performance of his duties on a
full-time basis during such 30 day period), and (iii) if the Executive's
employment is terminated pursuant to Section 4.1(c), 4.1(d), 4.2 or 4.3, the
date specified in the Notice of Termination; provided, that in the case of
termination under any of such provisions, the Notice of Termination and
termination are in compliance with the provisions of such Sections.

     5. Compensation Upon Termination--Severance Pay.

     5.1. If the Executive's employment is terminated under the provisions of
Section 4.1(a), 4.1(b), 4.1(c) or 4.3, the Company shall pay to the Executive
(or his estate) his earned Base Salary, and any earned but unpaid Performance
Bonus and benefits through the Date of Termination, including, but not limited
to, accrued vacation, and the Executive shall not be entitled to any other
compensation or severance pay.

     5.2. If the Company shall terminate the Executive's employment without
Cause under Section 4.1(d), or if the Executive shall terminate his employment
for Reason pursuant to Section 4.2, then the Company shall pay the Executive
following amounts and benefits:

               (i) An amount equal to his Base Salary (the "Severance Amount")
for a period of twelve (12) months following the Date of Termination (the
"Severance Period"). The amount payable under this Section 5.2(i) shall be in
addition to any other cash amounts due and payable, including, but not limited
to, accrued vacation.

               (ii) The Executive's coverage under the Company's life, health
and dental insurance plans will remain in effect, and the Executive will be
entitled to continue to participate in the Company's retirement plans at the
Company's expense (provided, that the Executive pays his contributory share)
during the Severance Period, unless the Executive notifies the Company in
writing that such coverage is no longer necessary. If, because of limitations
required by third parties or imposed by law, the Executive cannot be provided
such benefits through the Company's plans, then the Company will provide the
Executive with substantially equivalent benefits on an aggregate basis, at its
expense.

     5.3. If, at any time during the twelve (12) month period following a Change
in Control, the Company or its successor shall terminate the Executive's
employment without


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Cause under Section 4.1(d), or if the Executive shall terminate his employment
for Reason pursuant to Section 4.2, then the Company shall, in addition to the
payments described in Section 5.2, pay the Executive an amount equal to the
Performance Bonus the Executive would have received for the bonus year in which
termination occurs (the "Severance Bonus Payment"), determined by assuming
achievement of all then-existing Company and individual goals for such year,
payable over the Severance Period.

     5.4. Any obligation of the Company to the Executive under Sections 5.2 and
5.3 shall be conditioned upon the Executive signing and returning to the Company
a timely and effective release of claims in the form provided by the Company
(the "Release of Claims"). The Release of Claims required for separation
benefits in accordance with Section 5.2 or Section 5.3 creates legally binding
obligations on the part of the Executive, and the Company and its Affiliates
therefore advise the Executive to seek the advice of an attorney before signing
it. Any Severance Amount or Severance Bonus Payment to which the Executive is
entitled hereunder shall be payable in accordance with the normal payroll
practices of the Company and will begin at the Company's next regular payroll
period which is at least five business days following the later of the effective
date of the Release of Claims or the date the Release of Claims, signed by the
Executive, is received by the Company, but the first payment shall be
retroactive to the next business day following the date of termination.

     6. Acceleration of Stock Options. Immediately upon the occurrence of any of
the following events, any options then held by the Executive to acquire shares
of the Company's Common Stock shall automatically, without further action by the
Executive, become fully vested and exercisable, and each such option shall
remain exercisable until the expiration of such options or until they sooner
terminate in accordance with their terms:

          (a) termination of this Agreement by the Company without Cause
pursuant to Section 4.1(d);

          (b) termination of this agreement by the Executive for Reason pursuant
to Section 4.2; and

          (c) upon a Change in Control of the Company. For purposes of this
Agreement the term: "Change in Control" shall mean:

               (i) a merger, consolidation of similar combination after which
50% or more of the voting stock of the surviving corporation is held by persons
who were not stockholders of the Company immediately prior to such merger or
combination;

               (ii) the sale, transfer or other disposition of all or
substantially all of the Company's assets to one or more persons (other than any
wholly owned subsidiary of the Company) in a single transaction or series of
related transactions; or

               (iii) any person or related group of persons (other than the
Company or a person who directly or indirectly controls, or is controlled by, or
is under common control with the Company) directly or indirectly acquires
beneficial ownership (determined pursuant to Rule 13d-3 promulgated under the
Securities Exchange Act of 1934, as amended) of securities comprising more than
50% of the total combined voting power of the Company's


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outstanding securities pursuant to a tender or exchange offer made directly to
the Company's stockholders.

     7. Miscellaneous.

     7.1. Notices. All notices required by or permitted under this Agreement
shall be given in writing and be deemed duly given upon personal delivery,
telecopy, nationally recognized courier or mailed, by registered or certified
mail, return receipt requested, postage prepaid, addressed to the other party at
the address shown above or at such other address or addresses as either party
shall designate to the other in accordance with this Section 7.1.

     7.2. Pronouns. Whenever the context may require; any pronouns used in this
Agreement shall include the corresponding masculine, feminine or neuter forms,
and the singular forms of nouns and pronouns shall include the plural, and vice
versa.

     7.3. Entire Agreement. This Agreement and the Non-Competition Agreement
constitute the entire agreement between the parties, and supersede all prior
agreements and understandings, whether written or oral, relating to the subject
matter of this Agreement.

     7.4. Amendment. This Agreement may be amended or modified only by a written
instrument executed by both the Company and the Executive.

     7.5. Governing Law. This Agreement shall be construed, interpreted and
enforced in accordance with the laws of the Commonwealth of Massachusetts.

     7.6. Successors and Assigns. This Agreement shall be binding upon and inure
to the benefit of both parties and their respective successors and assigns,
including any corporation with which, or into which the Company may be merged or
which may succeed to its assets or business. Provided, however, that the
obligations of the Executive are personal and shall not be assigned by him; and
provided further, that the Company shall be and remain liable for the payment to
the Executive of all compensation payable to the Executive hereunder, except as
and to the extent otherwise agreed to by the Executive in his absolute
discretion. During the Executive's lifetime, this Agreement and all rights of
the Executive hereunder shall be enforceable by the Executive's spouse, heirs,
distributees, or other legal representatives in the event the Executive is
unable to act on his own behalf for any reason whatsoever.

     7.7. Waivers. No delay or omission by the Company in exercising any right
under this Agreement shall operate as a waiver of that or any other right. A
waiver or consent given by the Company on any one occasion shall be effective
only in that instance, and shall not be construed as a bar or waiver of any
right on any other occasion.

     7.8. Captions. The captions of the sections of this Agreement are for the
convenience of reference only and in no way define, limit or affect the scope or
substance of any section of this Agreement.

     7.9. Severability. In case any provision of this Agreement shall be
invalid, illegal or otherwise unenforceable, the validity, legality and
enforceability of the remaining provisions shall in no way be affected or
impaired thereby.


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     7.10. Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, and all of which
together shall constitute one and the same instrument.

                      [THE NEXT PAGE IS THE SIGNATURE PAGE]


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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
date set forth above.

                                        EXECUTIVE


                                        /s/ Morey Kraus
                                        -------------------------------------
                                        Morey Kraus


                                        VIACELL, INC.


                                        By: /s/ Marc D. Beer
                                            ------------------------------------
                                        Name: Marc D. Beer
                                        Title: President and Chief Executive
                                               Officer


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