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                                                                  EXHIBIT 10.103





                            NEXELL THERAPEUTICS, INC.
                          RETENTION AND SEVERANCE PLAN
                                       AND
                            SUMMARY PLAN DESCRIPTION

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                            NEXELL THERAPEUTICS, INC.
                          RETENTION AND SEVERANCE PLAN
                                FOR EMPLOYEES AND
                            SUMMARY PLAN DESCRIPTION

Effective July 24, 2001, this document outlines the terms and conditions of the
Nexell Therapeutics, Inc. Retention and Severance Plan maintained by Nexell
Therapeutics, Inc. to provide severance benefits and certain bonus payments to
eligible employees of the Company in anticipation of their termination of
employment. This document shall serve as both the plan document and the summary
plan description, as such terms are defined under the Employee Retirement Income
Security Act of 1974, as amended ("ERISA") and the regulations issued
thereunder. The Plan is intended to qualify as an employee welfare benefit plan
under ERISA, and it shall be interpreted and construed in a manner consistent
with such intention.

                                    ARTICLE I
                                   DEFINITIONS

The following capitalized words and phrases, when used in the text of the Plan
document, shall have the meanings set forth below. Words used in the Plan in the
singular shall include the plural and in the plural the singular and the gender
of words used shall be construed to include whichever gender may be appropriate
under any particular circumstances.

1.1      Annual Base Pay
         ---------------

         "Annual Base Pay" means the Participant's annual base salary or wages
         in effect on the date of the Participant's termination of employment
         with the Company, exclusive of overtime pay, incentive payments, bonus
         payments, commissions and other miscellaneous payments.

1.2      Board
         -----

         "Board" means the Board of Directors of the Company or any individual
         or committee appointed by the Board of Directors of the Company and
         vested with the authority to carry out the duties as allocated to the
         Board of Directors of the Company in the Plan or otherwise by the Board
         of Directors of the Company.

1.3      COBRA Contribution Benefit
         --------------------------

         "COBRA Contribution Benefit" means the benefit described in, and
         subject to the terms of, Section 2.2(b).

1.4      Code
         ----

         "Code" means the Internal Revenue Code of 1986, as amended.

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1.5      Company
         -------

         "Company" means Nexell Therapeutics, Inc., or any successor entity
         thereof.

1.6      Employee
         --------

         "Employee" means a person classified by the Employer as an employee,
         but excluding the Chief Executive Officer of the Company and any other
         Senior Staff Member.

1.7      Participant
         -----------

         "Participant" means an Employee who is entitled to receive a Severance
         Benefit or a Retention Bonus.

1.8      Plan
         ----

         "Plan" means the Nexell  Therapeutics,  Inc.  Retention and Severance
         Plan as set forth herein and as may be amended from time to time.

1.9      Retention Bonus
         ---------------

         "Retention Bonus" means the benefit described in, and subject to the
         terms of, Section 3.

1.10     Senior Staff Member
         -------------------

         "Senior Staff Member" means an Employee who is designated by the
         Company as a member of the Company's senior staff.

1.11     Severance Benefit
         -----------------

         "Severance Benefit" means the benefit described in, and subject to the
         terms of, Section 2.

1.12     Severance Payment
         -----------------

         "Severance Payment" means the benefit described in, and subject to the
         terms of, Section 2.2(a).

1.13     Weekly Base Pay
         ---------------

         "Weekly Base Pay" means the Participant's base salary or wages in
         effect on the date of the Participant's termination of employment with
         the Company, exclusive of overtime pay, incentive payments, bonus
         payments, commissions and other miscellaneous payments, appropriately
         converted to a weekly amount.

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                                    SECTION 2
                               SEVERANCE BENEFITS

2.1      Eligibility. An Employee whose employment with the Company is
         -----------
         involuntarily terminated on or after July 24, 2001 but no later than
         March 31, 2002, other than for cause as defined below, shall be
         eligible to receive a Severance Benefit. Involuntary termination of
         employment, other than for cause, for purposes of the Plan includes but
         is not limited to job elimination or staff reductions. Notwithstanding
         the preceding sentence, an Employee whose employment termination is
         described in subsections (a), (b) and (c) of this Section 2.1 shall not
         be eligible to receive a Severance Benefit.

         (a)      Involuntary Termination for Cause. An Employee whose
                  ---------------------------------
                  employment with the Company is involuntarily terminated for
                  cause will not be eligible to receive a Severance Benefit.
                  Involuntary termination of employment for cause for purposes
                  of the Plan and as determined by the Company includes but is
                  not limited to unsatisfactory job performance, violation of
                  the Company's policies or other misconduct, as determined
                  within the sole and absolute discretion of the Board.

         (b)      Voluntary  Termination.  As determined by the Company, an
                  ----------------------
                  Employee who voluntarily terminates employment with the
                  Company is not eligible to receive a Severance Benefit.

         (c)      Employment Continuation. As determined by the Company, an
                  -----------------------
                  Employee whose employment with the Company is involuntarily
                  terminated but who has received an offer of regular or
                  transitional employment from Baxter as of the date of such
                  termination of employment with the Company will not be
                  eligible to receive a Severance Benefit.

2.2      Severance Benefit. An Employee entitled to receive a Severance
         ------------------
         Benefit under Section 2.1 shall receive the following benefits:

         (a)      Severance Payment. The Severance Payment shall be a lump sum
                  -----------------
                  payment equal to a multiple of the Employee's Weekly Base Pay.
                  The multiple shall not be less than two (2) or greater than
                  eight (8) and shall be determined in the sole discretion of
                  the Board based on the Employee's position at the time of his
                  or her termination of employment.

         (b)      COBRA Contribution Benefit. With respect to an Employee
                  --------------------------
                  participating in a group health plan sponsored by the Company
                  on the date of his or her termination of employment, the COBRA
                  Contribution Benefit shall be a lump sum payment equal to the
                  cost of the applicable premium that the Employee would have to
                  pay for the first three months of continuation of coverage
                  under such group health plan sponsored by the Company upon
                  termination of employment if the Employee

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                  elected continuation of coverage under Section 4980B(f) of
                  the Code with respect to the Employee and all dependents
                  covered under the group health plan on the date the Employee
                  terminates employment. With respect to an Employee who is not
                  participating in a group health plan sponsored by the Company
                  on the date of his or her termination of employment, the COBRA
                  Contribution Benefit shall be $500.00.

         The Company shall make any lump sum payments which are part of the
         Severance Benefit to a Participant as soon as administratively
         practicable following the later of the Company's receipt of an executed
         separation release and acknowledgment, as described in Section 2.3, and
         the expiration of any waiting periods described in such separation
         release.

2.3      Separation Release and Acknowledgment. The receipt of a Severance
         --------------------------------------
         Benefit described under this Section 2 is conditioned upon the
         following

         (a)      the Participant's signing of a release deemed appropriate
                  by the Company in which the Participant releases and/or
                  waives any and all claims the Participant may have against the
                  Company;

         (b)      the release described in Section 2.3(a) becoming effective;
                  and

         (c)      any other requirements as determined solely by the Company
                  which are related to the Participant's termination of
                  employment with the Company.

         The Company has the sole and absolute discretion to determine the
         appropriateness of any release described in Section 2.3(a).

                                    SECTION 3
                                 RETENTION BONUS

3.1      Eligibility. An Employee who is actively employed on September 14, 2001
         -----------
         and who either (i) continues to be employed by the Company through
         December 31, 2001 or (ii) involuntarily terminates employment, other
         than for cause as described in Section 2.1(a), with the Company prior
         to December 31, 2001, shall be eligible to receive the Retention Bonus.
         The Company shall determine whether the eligibility requirements
         described in this Section 3.1 have been met by an Employee.

3.2      Retention Bonus. An Employee entitled to receive a Retention Bonus
         ---------------
         under Section 3.1 shall receive a lump sum payment equal to twenty-five
         percent (25%) of the Employee's Annual Base Pay as soon as practicable
         following the earlier of (i) December 31, 2001, or (ii) his or her
         termination of employment.

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                                    SECTION 4
                              PAYMENTS AND FUNDING

4.1      Disbursement of Payments. With respect to amounts paid by the Company
         ------------------------
         to a Participant in accordance with Sections 2 and 3, the appropriate
         withholding taxes and any other monies, debts or financial obligations
         owed to the Company by the Participant will be deducted from all
         benefit payments.

4.2      Funding. The Plan is unfunded for purposes of ERISA and the Code.
         -------
         All benefits under the Plan shall be paid from the general assets of
         the Employer.

                                    SECTION 5
                            ADMINISTRATION AND CLAIMS

5.1      Plan Administrator. The Board is the administrator of the Plan and has
         ------------------
         sole and absolute power and discretion to interpret and construe the
         terms and provisions of the Plan. Except as otherwise set forth in the
         Plan, such power and discretion shall include but not be limited to the
         authority to determine eligibility for participation in the Plan and
         the receipt of benefits under the Plan. All decisions of the Board are
         final, binding and conclusive. Except as provided herein, any
         delegation of the powers and authority of the Board must be made
         pursuant to a written document. The Board may be contacted at the
         following address and phone number:

                  Nexell Therapeutics, Inc.
                  9 Parker
                  Irvine, CA 92618-1605
                  949-470-9011

5.2      Claims for Benefits. Benefits will be paid to eligible Participants
         -------------------
         pursuant to Sections 2, 3 and 6. Any Participant who believes that he
         or she has not received a benefit to which he or she is entitled may
         file a claim with the Chief Executive Officer of the Company setting
         forth his or her claim. Upon receipt of a claim, the Chief Executive
         Officer shall advise the Claimant that a reply will be forthcoming
         within a reasonable period of time, but ordinarily not later than
         ninety days, and shall, in fact, deliver such reply within such period.
         However, the Chief Executive Officer may extend the reply period for an
         additional ninety days for reasonable cause. If the reply period will
         be extended, the Chief Executive Officer shall advise the Participant
         in writing during the initial 90-day period indicating the special
         circumstances requiring an extension and the date by which the Chief
         Executive Officer expects to render the benefit determination. If the
         claim is denied in whole or in part, the Chief Executive Officer will
         render a written opinion using language calculated to be understood by
         the Participant setting forth:

                  (a)      the specific reason or reasons for denial;


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                  (b)      the specific references to pertinent Plan provisions
               on which the denial is based;

                  (c)      a description of any additional  material or
               information  necessary for the  Participant to perfect the claim
               and an explanation why such material or such information is
               necessary;

                  (d)      appropriate  information as to the steps to be taken
               if the Participant  wishes to submit the claim for review,
               including a statement of the Participant's right to bring a civil
               action under Section 502(a) of ERISA following an adverse benefit
               determination on review; and

                  (e)      the time limits for requesting a review under Section
               7.3.

         If the claim is approved, the Participant's benefits will be adjusted
         accordingly.

5.3      Appeal of Denials of Benefits. A Participant who receives notice of
         -----------------------------
         denial of benefits under Section 7.2 must appeal to the Board in
         writing within sixty (60) days after the receipt of the written notice.
         Such request must be addressed to the Board at the Company's then
         current address. The Participant or his or her duly authorized
         representative may submit written comments, documents, records or other
         information relating to the denied claim, which such information shall
         be considered in the review under Section 7.4 without regard to whether
         such information was submitted or considered in the initial benefit
         determination. The Participant or his or her duly authorized
         representative shall be provided, upon request and free of charge,
         reasonable access to, and copies of, all documents, records and other
         information which (i) was relied upon by the Chief Executive Officer in
         making his or her initial claims decision, (ii) was submitted,
         considered or generated in the course of the Chief Executive Officer
         making his or her initial claims decisions, without regard to whether
         such instrument was actually relied upon by the Chief Executive Officer
         in making his or her decision or (iii) demonstrates compliance by the
         Chief Executive Officer with his or her administrative processes and
         safeguards designed to ensure and to verify that benefit claims
         determinations are made in accordance with governing Plan documents and
         that, where appropriate, the Plan provisions have been applied
         consistently with respect to similarly situated claimants. If the
         Participant does not request a review of the Chief Executive Officer's
         determination within such 60-day period, he or she shall be barred and
         estopped from challenging such determination.

5.4      Review of Appeals. Within a reasonable period of time, ordinarily not
         -----------------
         later than sixty days, after the Board's receipt of a request for a
         review, it will review all appeals to reach a final decision as to
         whether the denial of benefits was justified. If special circumstances
         require that the sixty-day time period be extended, the Board will
         notify the Participant within the initial 60-day period indicating the
         special circumstances requiring an extension and the date by which the
         Board expects to render its decision on review, which shall be as soon
         as possible but not later than 120 days after receipt of the request
         for review. The Board has discretionary authority to determine
         eligibility for benefits and to interpret the terms of the Plan.
         Benefits under the Plan will be paid only if the Board decides in its
         discretion that the

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          Participant is entitled to them. The decision of the Board shall be
          final and non-reviewable unless found to be arbitrary and capricious
          by a court of competent review. Such decision will be binding upon the
          Company and the Participant. If the Board makes an adverse benefit
          determination on review, the Board will render a written opinion using
          language calculated to be understood by the Participant setting forth:

                  (a)      the specific reason or reasons for denial;


                  (b)      the specific references to pertinent Plan provisions
               on which the denial is based;

                  (c)      a statement that the Participant is entitled to
               receive, upon request and free of charge, reasonable access to,
               and copies of, all documents, records and other information which
               (i) was relied upon by the Board in making its decision, (ii) was
               submitted, considered or generated in the course of the Board
               making its decision, without regard to whether such instrument
               was actually relied upon by the Board in making its decision or
               (iii) demonstrates compliance by the Board with its
               administrative processes and safeguards designed to ensure and to
               verify that benefit claims determinations are made in accordance
               with governing Plan documents and that, where appropriate, the
               Plan provisions have been applied consistently with respect to
               similarly situated claimants.

                  (d) a statement of the Participant's right to bring civil
               action under Section 502(a) of ERISA following an adverse benefit
               determination on review.

5.5      Indemnification of Administrator
         --------------------------------

         The Company agrees to indemnify and to defend to the fullest extent
         permitted by law any employee of the Company serving as the Plan
         Administrator or as a member of the Board designated as Plan
         Administrator (including any employee or former employee who formerly
         served as Plan Administrator or as a member of the Board) and any
         employee action on behalf of the Company as Plan Administrator against
         all liabilities, damages, costs and expenses (including attorney's fees
         and amounts paid in settlement of any claims approved by the Company)
         occasioned by any act or omission to act in connection with the Plan if
         such act or omission is taken in good faith and is neither criminal nor
         willful misconduct.

                                    SECTION 6
                               GENERAL PROVISIONS

6.1      No Guarantee of Employment or Other Benefits. Except for Employees
         --------------------------------------------
         subject to an employment agreement which states otherwise, employment
         with the Company is on an "at will" basis. This means that the
         employment  relationship  may be terminated at any time by either the
         Employee or the Company for any reason not expressly prohibited by law.
         Any

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         representation to the contrary is invalid and unenforceable and should
         not be relied upon, unless set forth in a written contract of
         employment, signed on behalf of the Company by an authorized officer.
         Participation in this Plan and the receipt of benefits under this Plan
         shall not automatically be deemed employment for purposes of any other
         employee benefit plan including, without limitation, participation in
         (i) any other benefit plan such as medical, dental, disability or other
         welfare benefit plan, (ii) any retirement or 401(k) plan or (iii) any
         other type of benefit.

6.2      Amendment or  Termination. The Company reserves the right to modify
         -------------------------
         or terminate the Plan at any time. The Company through the Board or
         any committee designated by the Board may amend the Plan pursuant to a
         formal resolution. If this is done, eligible Participants will be
         notified of any important changes.

6.3      Assignment of Benefits. A Participant's right to benefits under the
         ----------------------
         Plan cannot be sold or assigned and such benefits are not subject to
         garnishment or attachment until they are actually paid.

                                    SECTION 7
                                ERISA PROVISIONS

7.1      Plan Sponsor. The Company is the sponsor of the Plan for purposes of
         ------------
         ERISA, and its name and address are as follows:

                  Nexell Therapeutics, Inc.
                  9 Parker
                  Irvine, CA 92618-1605

7.2      Agent for Service of Legal Process. The name and address of the
         ----------------------------------
         designated agent for service of legal process under the Plan is:

                  Nexell Therapeutics, Inc.
                  General Counsel
                  9 Parker
                  Irvine, CA 92618-1605

7.3      Fiscal Year of the Plan. The fiscal year of the Plan begins on January
         -----------------------
         1 and ends on December 31 of each calendar year. The first year of the
         Plan shall be a short plan year beginning on July 24, 2001 and ending
         on December 31, 2001.

7.4      Employer I.D. Number. The Company's employer identification number for
         --------------------
         federal income tax purposes is 52-2059352.

7.5      Plan Number. The three-digit number assigned to the Plan for
         -----------
         identification purposes is 501.


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7.6      Type of Plan and Plan Administration. This Plan is a severance pay plan
         ------------------------------------
         which is a welfare benefit plan under ERISA. Benefits are
         self-administered.

7.7      Governing Laws. This Plan shall be construed, governed and administered
         --------------
         in accordance with the laws of the State of California to the extent
         such laws are not preempted by ERISA or the Code.

7.8      Statement of ERISA Rights. Participants in the Plan are entitled to
         -------------------------
         certain rights and protections under ERISA. ERISA provides that all
         Plan Participants are entitled to:

         Receive Information About Your Plan and Benefits

              Examine, without charge, at the Plan Administrator's office and at
              other specified locations, such as worksites and union halls, all
              documents governing the Plan, including insurance contracts and
              collective bargaining agreements, and a copy of the latest annual
              report agreements, and a copy of the latest annual report (Form
              5500 Series) filed by the Plan with the U.S. Department of Labor
              and available at the Public Disclosure Room of the Pension and
              Welfare Benefit Administration.

              Obtain, upon written request to the Plan Administrator, copies of
              documents governing the operation of the Plan, including insurance
              contracts and collective bargaining agreements, and copies of the
              latest annual report (Form 5500 Series) and updated summary plan
              description. The Plan Administrator may make a reasonable charge
              for the copies.

         Prudent Actions by Plan Fiduciaries

              In addition to creating rights for Plan Participants, ERISA
              imposes duties upon the people who are responsible for the
              operation of the Plan. The people who operate the Plan, called
              "fiduciaries" of the Plan, have a duty to do so prudently and in
              the interest of all Plan Participants and beneficiaries. No one,
              including the Company or any other person, may fire any
              Participant or otherwise discriminate against any Participant in
              any way to prevent him or her from obtaining benefits or
              exercising his or her rights under ERISA.

         Enforce Your Rights

              If a Participant's claim for benefits is denied or ignored, in
              whole or in part, the Participant has a right to know why this was
              done, to obtain copies of documents relating to the decision
              without charge, and to appeal any denial, all within certain time
              schedules. Under ERISA, there are steps a Participant can take to
              enforce the above rights. For instance, if a Participant requests
              a copy of Plan documents or the latest annual report from the Plan
              and does not receive them within thirty (30) days, he or she may
              file suit in a federal court. In such a case, the court may
              require the Company to provide the materials and pay the
              Participant up to $110 a day until he or she receives the
              materials, unless the materials were not sent because of reasons
              beyond the control

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              of the Company. If a Participant has a claim for benefits which is
              denied or ignored, in whole or in part, he or she may file suit in
              a federal court. If it should happen that Plan fiduciaries misuse
              the Plan's money, or if a Participant is discriminated against for
              asserting his or her rights, he or she may seek assistance from
              the U.S. Department of Labor, or he or she may file suit in a
              federal court. The court will decide who should pay court costs
              and legal fees. If the Participant is successful, the court may
              order the person he or she has sued to pay these costs and fees.
              If the Participant loses, the court may order him or her to pay
              these costs and fees if, for example, it finds that the
              Participant's claim is frivolous.

         Assistance with Your Questions

              Any Participant who has questions about the Plan should contact
              the Company. Any Participant who has any questions about this
              statement or about his or her rights under ERISA, or needs
              assistance in obtaining documents from the Plan Administrator,
              should contact the nearest Area Office of the Pension and Welfare
              Benefits Administration, U.S. Department of Labor, listed in the
              telephone directory or the Division of Technical Assistance and
              Inquiries, Pension and Welfare Benefits Administration, U.S.
              Department of Labor, 200 Constitution Avenue N.W., Washington,
              D.C. 20210. A Participant may also obtain certain publications
              about his or her rights and responsibilities under ERISA by
              calling the publications hotline of the Pension Welfare Benefits
              Administrator.

         IN WITNESS WHEREOF, Nexell Therapeutics, Inc. has caused this Plan to
be executed by a duly authorized officer as of this the 30th day of January,
2002.

                                        NEXELL THERAPEUTICS, INC.

                                        By:_____________________________________
                                                  President and CEO


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                   AMENDMENT TO THE NEXELL THERAPEUTICS, INC.
                          RETENTION AND SEVERANCE PLAN
                                       AND
                            SUMMARY PLAN DESCRIPTION

         WHEREAS, Nexell Therapeutics, Inc. ("Company") previously established
the Nexell Therapeutics, Inc. Retention and Severance Plan for Employees
("Plan"); and

         WHEREAS, the Company reserved the right to amend the Plan; and

         WHEREAS, the Company desires to amend the Plan to extend certain dates
related to the eligibility for a severance benefit;

         NOW, THEREFORE, the Plan is amended by deleting the first sentence of
Section 2.1 and replacing it with the following:


         "An Employee whose employment with the Company is involuntarily
         terminated on or after July 24, 2001 but no later than June 30, 2002,
         other than for cause as defined below, shall be eligible to receive a
         Severance Benefit."

         IN WITNESS WHEREOF, the Company has caused this amendment to be
executed this 25th day of March, 2002.

                                             NEXELL THERAPEUTICS, INC.

                                             By_________________________________
                                               William A. Albright, Jr.
                                               President and CEO