Methods of removing alpha-galactose

Abstract

Tissue products lacking a desired percentage of immunogenic epitopes, such as galactose alpha-1,3 galactose epitopes, are provided. Methods of making and using the tissue products are also provided.

What is claimed is: 
     
         1 . A method of preparing a tissue product, comprising
 selecting at least one collagen-containing tissue matrix containing galactose alpha-1,3-galactose moieties; and   contacting the at least one tissue matrix with at least one proteolytic enzyme selected from bromelain, trypsin, and dispase under conditions sufficient to remove galactose alpha-1,3-galactose moieties from the tissue.   
     
     
         2 . The method of  claim 1 , wherein the at least one collagen-containing tissue matrix is contained within a cellular tissue, and wherein the method further comprise decellularizing the cellular tissue. 
     
     
         3 . The method of  claim 2 , wherein the tissue matrix is completely decellularized. 
     
     
         4 . The method of  claim 1 , wherein alpha-galactose is substantially or completely removed from the collagen-containing tissue matrix. 
     
     
         5 . The method of  claim 1 , wherein the proteolytic enzyme removes galactose alpha-1,3-galactose moieties without damaging the at least one tissue matrix. 
     
     
         6 . The method of  claim 1 , further comprising performing an assay to determine if galactose alpha-1,3-galactose moieties have been removed from the at least collagen-containing tissue matrix. 
     
     
         7 . The method of  claim 6 , wherein the assay comprises measuring a concentration of galactose alpha-1,3-galactose moieties. 
     
     
         8 . The method of  claim 6 , wherein the assay comprises an histochemical assay. 
     
     
         9 . The method of  claim 6 , wherein the assay comprises an immuno assay. 
     
     
         10 . The method of  claim 1 , wherein the proteolytic enzyme is trypsin, and the trypsin is used at a concentration ranging from about 0.0001% to about 0.1% and for a period of time ranging from about 0.5 hours to about 24 hours. 
     
     
         11 . The method of  claim 1 , wherein the proteolytic enzyme is at least one of bromelain and dispase, and the proteolytic enzyme is used at a concentration ranging from about 10 units/liter to about 200 units/liter and for a period of time ranging from about 1 hour to about 24 hours. 
     
     
         12 . The method of  claim 1 , further comprising contacting the tissue with alpha-galactosidase. 
     
     
         13 . The method of  claim 1 , wherein the at least one collagen-containing tissue matrix comprises a tissue matrix from at least one of bone, skin, adipose tissue dermis, intestine, urinary bladder, tendon, ligament, muscle, fascia, vascular, neurologic, vessel, liver, heart, lung, kidney, and cartilage tissue. 
     
     
         14 . The method of  claim 1 , wherein tissue from one or more different animals or tissue sources are used. 
     
     
         15 . The method of  claim 1 , wherein the at least one collagen-containing tissue matrix is a porcine tissue matrix. 
     
     
         16 . The method of  claim 1 , wherein the at least one collagen-containing tissue matrix consists of a porcine acellular dermal tissue matrix 
     
     
         17 . The method of  claim 1 , further comprising adding one or more viable and histocompatible cells to the tissue product. 
     
     
         18 . The method of  claim 17 , wherein the one or more cells are mammalian cells. 
     
     
         19 . The method of  claims 17 , wherein the one or more cells are stem cells. 
     
     
         20 . The method of  claim 1 , further comprising treating the at least one collagen-containing tissue matrix to reduce bioburden.