Exhibit 10.28

THIRD AMENDMENT TO THE
BLOOD DONOR CENTER MANAGEMENT
COMMUNITY MOBILE BLOOD COLLECTIONS
SERVICES AGREEMENT

This THIRD
AMENDMENT (the “THIRD AMENDMENT”) is entered into as May 1, 2009 (the “Amendment Effective Date”) by and
between University of Southern California, on behalf of USC University Hospital(“Hospital”), a medical center
located at 1500 San Pablo Street, Los Angeles, California 90033 and HemaCare Corporation(“HemaCare”), located
at 15350 Sherman Way, Suite 350, Van Nuys, California 91406.

RECITAL

A.	USC
University Hospital, Inc. (“USCUH”) and HemaCare entered into that certain Blood Donor Center Management and Community
Mobile Blood Collections Services Agreement effective May 1, 2004, which was amended by the First Amendment effective May 1, 2006,
and further amended by the Second Amendment effective May 1, 2007, which collectively is referred to as the “Agreement”.

B.	Pursuant
to the Asset Purchase Agreement among USCUH, Tenet Healthsystem Norris, Inc. and the University of Southern California, dated February
9, 2009, Hospital assumed the Agreement from USCUH, effective April 1, 2009.

C.	Hospital
and HemaCare desire to amend the terms of the Agreement as set forth herein below.

NOW, THEREFORE,
the parties hereto, based upon the above recitals and the covenants and conditions set forth herein, agree as follows:

1.	TERM
AND TERMINATION. Section VI, paragraph A of the Agreement shall be amended and is replaced in its entirety as follows:

This agreement shall commence
May 1,2009 and continue for a term of two (2) years.

2.	HEMACARE'S
COMPENSATION. For Services rendered on or after May 1, 2009 pursuant to this Agreement, Hospital shall pay HemaCare in
accordance with the revised Fee Schedule, Attachment “I,” attached hereto and made part hereof by this reference. At
the end of the initial twelve (12) months of this contract term, the parties agree to meet and confer regarding the fees for services
rendered during the remainder of the term. Any modifications to the Fee Schedule shall take effect only upon mutual written agreement
of both parties and shall apply to services rendered on or after the date of such mutual written agreement.

3.	GENERAL.
If provisions of this Amendment and the Agreement conflict, the provisions of this Amendment shall prevail. Except as specifically
amended herein, all terms and conditions of the Agreement shall remain in full force and effect.

4.	LIMITED
EXCLUSIVITY. Section V, paragraph E of the Agreement shall be amended and is replaced in its entirety as follows:

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It is agreed and acknowledged
by the parties that, as an independent contractor, HemaCare retains the right to contract with and provide services to entities
and individuals other than Hospital and its patients, and nothing in this Agreement be interpreted as limiting or restricting in
any way HemaCare's right to do so. Hospital agrees that HemaCare will be the sole outside provider of the described Blood Donor
Center and Community Mobile Blood Drive Program during the term of this Agreement and Hospital agrees not to contract with any
other third party to conduct the Services contemplated by this Agreement, unless HemaCare is unable to meet and/or perform its
obligations under this Agreement or as otherwise provided herein. Nothing in the foregoing sentence shall prohibit Hospital from
purchasing blood products from any vendor at any time. Upon mutual written agreement of both parties HemaCare may open complimentary
Donor Centers for benefit of the Hospital.

5.	NON-SOLICITATION.
Section VIII, paragraph C of the Agreement shall be amended and is replaced in its entirety as follows:

HemaCare and Hospital mutually
agree not to solicit each other's employees, except upon written permission. The prohibition period for non-solicitation will extend
for twenty-four (24) months post-HemaCare or Hospital employment and for twenty-four (24) months after the termination off this
agreement. The penalty for breach will be an amount equal to the employee's annual compensation prior to termination of services
with the aggrieved party. Nothing in the foregoing covenant shall restrict either party from entering into employment discussions
with an employee of the other party who initiates such discussions.

6.	ASSIGNMENT.
Section VIII, paragraph F of the Agreement shall be amended and is replaced in its entirety as follows:

Neither party may assign
this Agreement, nor the rights and obligations therein, to a third party without the express written consent of the other party;
however, either party may assign this Agreement, and its rights and obligations therein, to any individual or entity that purchases
all or substantially all of either party's assets or stock, or any entity that succeeds to a merger between either party and another
entity or entities, or to any entity controlled by either party, or to any entity controlling either party, or any entity under
common control with either party.

7.	LIMITATION
OF LIABILITY.Section VIII, paragraph K, shall be added and incorporated to the Agreement as follows:

The parties acknowledge and
agree that both Hospital and HemaCare shall only be entitled to reasonably foreseeable direct damages, if any, which arise from
(i) any indemnification provision under this Agreement, as amended, (ii) any beach of any provision under this Agreement, as amended,
and (iii) any breach under Section VIII, paragraph C of the Agreement, as amended, which relates to the non-solicitation of employees
and the penalty associated therewith. Except for direct damages as provided in the preceding sentence, to the maximum extent permitted
by law, it is the intent of the parties that neither Hospital nor HemaCare shall be responsible for any incidental, consequential,
indirect, special, punitive or exemplary damages of any kind, including damages for lost goodwill, lost profits, lost business
or other indirect damages based on contract, negligence, tort (including strict liability) or other legal theory, as a result of
a breach of any warranty or any other term of this Agreement, and regardless of whether a party was advised or had reason to know
of the possibility of such damages in advance.



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|UNIVERSITY OF SOUTHERN CALIFORNIA, on behalf of USC UNIVERSITY HOSPITAL |                         | HEMACARE CORPORATION
|----------------------------------------------------------------------- | ----------------------- | --------------------
|                                                                        |                         |                     
|/s/                                                                     | Scott Evans             |                     
|By:                                                                     | Scott Evans, PharmD.    |                     
|Title:                                                                  | Chief Operating Officer |                     
|Date:                                                                   |                         |                     



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HEMACARE CORPORATION
BLOOD PRODUCTS FEE SCHEDULE
USC UNIVERSITY HOSPITALHospital Services Direct Order Lines
800-826-7962 OR 818-986-3977

|COMPONENT                                                                             | FEE PER UNIT
|------------------------------------------------------------------------------------- | ------------
|Platelet Pheresis, Leukoreduced                                                       | $[l]1       
|Two (2) free returns per month. Additional returns at $200.00 per unit restocking fee |             
|Platelet Pheresis, Leukoreduced, Pediatric Unit                                       | $[l]        
|Special order non-returnable.                                                         |             
|Red Blood Cells                                                                       | $[l]        
|Leukoreduced Red Blood                                                                | $[l]        
|Directed Platelet Pheresis                                                            | $[l]        
|Directed Red Blood Cells                                                              | $[l]        
|Directed Leukoreduced Red                                                             | $[l]        
|Autologous Red Blood Cells*                                                           | $[l]        
|Autologous Leukoreduced Red Blood                                                     | $[l]        
|ADDITIONAL
    SERVICES                                                               |             
|Special Distribution Surcharge                                                        | $[l]        
|Charged for product pick-up or transfer                                               |             

NOTE:

*All autologous and directed
donor services provided at the HemaCare Blood & Platelet Donor Center and the USC Blood Donor Center.



| | EFFECTIVE DATE:  5-1-09
to 4-30-101
| | -----------------------------------



CONFIDENTIAL INFORMATION

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1
Terms represented by this symbol are considered confidential. These confidential terms have been omitted pursuant
to a Confidential Treatment Request filed with the Securities and Exchange Commission (“SEC”) and have been filed separately
with the SEC.



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HCC# 195

Attachment A
BLOOD PRODUCTS FEE SCHEDULE
USC UNIVERSITY HOSPITALHospital Services Direct Order Lines
800-826-7962 OR 818-986-3977

|COMPONENT                                                                                                         | FEE PER UNIT
|----------------------------------------------------------------------------------------------------------------- | ------------
|Platelet Pheresis, Leukoreduced                                                                                   | $[l]2       
|Hospital must purchase an average of 300 platelets per month to maintain Depot Status. No restocking fee applies. |             
|Platelet Pheresis, Leukoreduced, Pediatric Unit                                                                   | $[l]        
|Special order non-returnable.                                                                                     |             
|Red Blood Cells                                                                                                   | $[l]        
|Leukoreduced Red Blood Cells                                                                                      | $[l]        
|Fresh Frozen Plasma                                                                                               | $[l]        
|Cryoprecipitate                                                                                                   | $[l]        
|Cryo-Poor Plasma                                                                                                  | $[l]        
|Directed Platelet Pheresis, Leukoreduced*                                                                         | $[l]        
|Directed Red Blood Cells*                                                                                         | $[l]        
|Directed Leukoreduced Red Cells*                                                                                  | $[l]        
|Autologous Red Blood Cells*                                                                                       | $[l]        
|Autologous Leukoreduced Red Blood Cells*                                                                          | $[l]        
|ADDITIONAL
    SERVICES                                                                                           |             
|Irradiation                                                                                                       | $[l]        
|CMV Negative Screening                                                                                            | $[l]        
|Shipping & Handling                                                                                               | [l]         
|STAT Delivery                                                                                                     | [l]         
|Special Distribution Surcharge                                                                                    | $[l]        
|Charged for product pick-up or transfer                                                                           |             

NOTE:

All autologous and directed donor
services provided at the HemaCare Blood & Platelet Donor Center and the USC Blood Donor Center.





| | EFFECTIVE DATE:    9110/20101
| | -----------------------------







CONFIDENTIAL INFORMATION










2
Terms represented by this symbol are considered confidential. These confidential terms have been omitted pursuant to a Confidential
Treatment Request filed with the SEC and have been filed separately with the SEC.



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