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                                                                   EXHIBIT 10.35

                                 [VIACELL LOGO]

October 10, 2004


Mary Thistle
9 Longview Drive
Chelmsford, MA 01824

Dear Mary,

On behalf of ViaCell, Inc. (the "Company"), I am pleased to extend our offer for
the new role of General Manager, ViaCell Reproductive Health. You continue to
deliver outstanding results in your work with ViaCell and you have made an
outstanding impression during your interim leadership of VRH. I am confident you
will succeed in this new role. Information about the details of our offer are
summarized below.


POSITION         General Manager, ViaCell Reproductive Health, reporting to Marc
                 Beer, Chief Executive Officer. This position is a key factor in
                 ViaCell's continued success, and I am confident that it will be
                 an exciting opportunity for you as well.

                 In this role, your duties will include the following:
                        -     Full P&L responsibility for ViaCell Reproductive
                              Health and its commercial business
                        -     Launch of our new Viacyte product
                        -     Successful development and execution of strategic
                              plans, staff and process to continue execution
                              against commercial goals and future growth in the
                              business.

COMPENSATION     The base salary for this position will be $220,000.00 per year
                 payable in bi-weekly installments of $8461.54. This salary will
                 be effective October 13, 2004, upon Board approval.

                 In addition, you will be eligible to participate in the
                 Management Bonus Plan at an annual target of 25% of base
                 salary, which is initially $55,000 at your new pay rate. This
                 bonus is payable annually based on agreed to company and
                 individual performance objectives. Your bonus payout is
                 determined based on achievement of both corporate and
                 individual goals.

STOCK OPTIONS    As an incentive for you to participate in the Company's future
                 growth, you will receive, subject to approval by our Board of
                 Directors, options to purchase an additional 50,000 shares of
                 our Common Stock (the "Options"). The Options will be incentive
                 stock options ("ISO's") to the extent allowable under the
                 Internal Revenue Code. The exercise price of the Options equals
                 the fair market value of our Common Stock as determined by the
                 Board of Directors on your effective date; your fair market
                 value price is $5.00 per share. The Options will vest quarterly
                 over four years beginning on the last day of the first quarter
                 after your effective date. The


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M. Thistle GM Offer
October 10, 2004
Page 2

                 Options will be granted under the Company's 1998 Equity
                 Incentive Plan pursuant to an ISO certificate or nonstatutory
                 stock option ("NSO") certificate, as appropriate, shall have a
                 term of ten years and contain such additional terms as shall
                 be determined by the Board of Directors of the Company or the
                 Compensation Committee thereof.

ADDITIONAL       ViaCell will provide for six months' severance pay in the event
EMPLOYMENT       of involuntary termination without cause or voluntary
TERMS            termination for good reason. If the Company shall terminate
                 your employment without "cause" or if you terminate your
                 employment for "good reason," then ViaCell will continue paying
                 your base salary and medical and dental benefit contributions
                 for a period of six months in accordance with its regular
                 payroll practices at such time. If the Company terminates your
                 employment with "cause," then ViaCell will continue paying your
                 base salary for a period of thirty days and all options will
                 cease to continue vesting as of the date of termination. The
                 term "cause" as used here means (i) your continued failure to
                 substantially perform your duties provided you are reasonably
                 notified of such failure and given reasonable time to correct
                 such failure, (ii) any misappropriation of funds, properties or
                 assets of the Company by you, (iii) any damage or destruction
                 of any property or assets of the Company caused by you, whether
                 resulting from your willful actions or willful omissions or
                 gross negligence; (iv) your being convicted of a felony; or (v)
                 any material breach of your employment obligations or of the
                 Intellectual Property and Confidential Information Agreement.
                 The term "good reason" as used here means any action by the
                 Company without your prior consent which results in (i) any
                 material diminution in your title, position, duties,
                 responsibilities or authority; or (ii) any breach by the
                 Company of any material provision contained herein.


I am very excited about the future of ViaCell and believe that the opportunities
presented for our continued commercial success will allow you significant
personal and professional growth. I am more confident than ever of our success
with you in this key role. I look forward to working closely with you over the
coming years ahead!


Sincerely,

/s/ MARC BEER

Marc Beer
Chief Executive Officer



/s/  MARY THISTLE
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Signature                           Date