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                                                                   Exhibit 10.57
                     Initial Offer Date: September 07, 2007

AMARESH BASU, PH.D.
15213 CALLE JUANITO
SAN DIEGO, CA  92129

Dear: Amaresh

On behalf of MicroIslet, Inc., a Nevada corporation ("MicroIslet") I am pleased
to present you with this employment offer under the following terms and
conditions:

Title:                     Vice-President of Research & Development

Start Date:                October 01, 2007 ("Start Date")

Salary:                    Semi-monthly salary of $6,250.00, paid in accordance
                           with our standard payroll practices, and subject to
                           withholding as required by law. You will be
                           classified as a Regular Full-Time Employee as defined
                           in our Employee Handbook.

Benefits:                  You will be eligible to participate in any benefit
                           plans offered to the employees of MicroIslet,
                           including medical and dental insurance for you and
                           your family. Premiums for medical and dental
                           insurance for you (and your dependents) are currently
                           covered at 100%.

                           MicroIslet observes eleven paid holidays per calendar
                           year. Our Paid Time Off ("PTO") policy is a
                           combination of vacation, personal, and sick days. PTO
                           hours will be accrued per pay period at the rate of
                           no less than fifteen (15) days of PTO per year.

                           A 401k package is available with multiple investment
options.

                           All of the above benefits are subject to change from
time to time.

Position Description:      In this position, you will report to the Chief
                           Executive Officer. You will be responsible to lead
                           the overall Research & Development function of the
                           Company in these areas: regulatory filings, assay
                           development, islet isolation and purification,
                           process development, and preclinical development. You
                           will be responsible for building, leading and
                           mentoring the development team to meet the various
                           stages of the development cycles, to develop
                           strategies and management of development projects, to
                           evaluate external technologies for potential
                           acquisition, to oversee the Research & Development
                           program's budgeting and planning activities, while
                           participating in partnership interactions and other
                           business development activities when requested. In
                           addition you will be responsible for identifying and
                           establishing a network of development capabilities,
                           resources, tools, processes and methods to maximize
                           the Company's success rate and to provide development
                           presentations to MicroIslet Executive Management,
                           Board of Directors, Scientific Advisors, and
                           Partners. Our duties are subject to change at the
                           discretion of MicroIslet management from time to
                           time.

Nature of Employment:      Your employment with MicroIslet will not be for any
                           specific term and may be terminated by you or by
                           MicroIslet at any time, with or without cause and
                           with or without notice. Any contrary representations
                           or agreements, either express or implied, which may
                           have been made to you, are superseded by this offer.
                           The at-will nature of your employment described in
                           this offer letter shall constitute the entire
                           agreement between you and MicroIslet concerning the
                           duration of your employment and the circumstances
                           under which either you or MicroIslet may terminate
                           the employment relationship. No person affiliated
                           with MicroIslet has the authority to enter into any
                           oral agreement that changes the at will status of
                           employment with MicroIslet. The at will term of your

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                           employment can only be changed in a writing signed by
                           you and by the Chief Executive Officer (CEO) or Chief
                           Financial Officer (CFO) of MicroIslet, and the
                           writing must expressly state the parties' intention
                           to modify the at will term of your employment. By
                           signing below and accepting this offer, you
                           acknowledge and agree that the length of your
                           employment, promotions, performance reviews, pay
                           adjustments, bonuses, increases in job duties or
                           responsibilities and other changes during employment
                           will not change the at will term of your employment
                           with MicroIslet, and will not create any implied
                           contract requiring cause for termination of
                           employment. YOUR STOCK OPTION GRANT DOES NOT CREATE
                           ANY IMPLIED PROMISE THAT YOU WILL BE EMPLOYED FOR ANY
                           SPECIFIC DURATION.

Stock Options:             Subject to approval of our Compensation Committee,
                           you will be granted a stock option to purchase shares
                           of common stock as soon as practicable after your
                           Start Date. The option will have an exercise price
                           equal to the fair market value of our common stock on
                           the date of grant, and will include all the terms as
                           defined in the Company's 2005 Equity Incentive Plan
                           The option will vest over three years, with the first
                           vesting date being six months after the grant date,
                           and the balance vesting monthly until the third
                           anniversary of the grant date.

Employment                 Policies: Additional terms of your employment may be
                           set forth in MicroIslet's Employment Policies, as
                           adopted or revised from time to time.

Inventions:                You will be required to sign the attached Proprietary
                           Information and Inventions Agreement ("Inventions
                           Agreement").

References:                The offer in this letter is subject to satisfactory
                           reference and background checks, to be completed by
                           MicroIslet within ten (10) days after execution of
                           this letter by you.

Arbitration:               You will be required to sign a Mutual Agreement to
                           Arbitrate ("Arbitration Agreement").

This letter, the Inventions Agreement, and the Arbitration Agreement constitute
the entire agreement between you and MicroIslet regarding your employment. All
prior or contemporaneous agreements, promises, communications and/or
understandings between you and MicroIslet, whether written or oral are
superseded by this letter, the Inventions Agreement and the Arbitration
Agreement. These agreements may be modified or changed only by a written
agreement signed by the CEO or CFO of MicroIslet, and the writing must expressly
state the parties' intention to modify an agreement by referring to such
agreement by name and date.

If you agree to the terms of your new employment, please sign this offer in the
space provided below signifying that you have read and accept the terms herein.
We look forward to your joining this great team as we pursue the goal of curing
Diabetes.

Sincerely,

/s/ Michael J. Andrews
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Michael J. Andrews
Chief Executive Officer


Agreed and accepted this 8th day of October, 2007


/s/ Amaresh Basu, Ph.D.
-----------------------
Amaresh Basu, Ph.D.