Methods of manufacture of immunocompatible amniotic membrane products

Abstract

Provided herein is a placental product comprising an immunocompatible amniotic membrane. Such placental products can be cryopreserved and contain viable therapeutic cells after thawing. The placental product of the present invention is useful in treating a patient with a tissue injury (e.g. wound or burn) by applying the placental product to the injury. Similar application is useful with ligament and tendon repair and for engraftment procedures such as bone engraftment.

1 - 19 . (canceled) 
     
     
         20 . A method of cryopreserving an amniotic membrane comprising:
 (a) isolating the amniotic membrane from the placenta;   (b) lysing red blood cells in the amniotic membrane, removing blood clots from the amniotic membrane, or a combination thereof; and   (c) cryopreserving the amniotic membrane in a cryopreservation medium at a freezing temperature;   wherein the cryopreserved amniotic membrane comprises at least 70% viable therapeutic cells,   wherein the viable therapeutic cells are native to the amniotic membrane,   wherein the viable therapeutic cells comprise two or more cell types selected from mesenchymal stem cells (MSCs), fibroblasts, and epithelial cells,   wherein the cryopreserved amniotic membrane does not include a chorionic membrane, and   wherein the cryopreserved amniotic membrane produces a non-immunogenic response in a mixed lymphocyte reaction assay.   
     
     
         21 . The method of  claim 20 , wherein the freezing temperature is −75° C. to −85° C. 
     
     
         22 . The method of  claim 20 , wherein the cryopreservation medium comprises a cell-permeating cryopreservative, a non-cell-permeating cryopreservative, or a combination thereof. 
     
     
         23 . The method of  claim 22 , wherein the cell-permeating cryopreservative comprises dimethylsulfoxide (DMSO). 
     
     
         24 . The method of  claim 23 , wherein the DMSO is in amount of about 2% to about 20% by volume of the cryopreservation medium. 
     
     
         25 . The method of  claim 22 , wherein the cryopreservation medium further comprises albumin. 
     
     
         26 . The method of  claim 25 , wherein the albumin is about 1% to about 15% by volume of the cryopreservation medium. 
     
     
         27 . The method of  claim 20 , wherein the lysing of red blood cells and removing of blood clots is performed using a phosphate buffered saline (PBS) and/or an anticoagulant citrate dextrose (ACD-A) solution. 
     
     
         28 . The method of  claim 20 , further comprising the step of treating the amniotic membrane with one or more antibiotics. 
     
     
         29 . The method of  claim 28 , wherein the one or more antibiotics are selected from gentamicin sulfate, vancomycin HCl, or amphotericin B.