Method for enzymatic treatment of tissue products

Abstract

Methods for treating tissue matrices and tissue matrices produced according to the methods are provided. The methods can include treating a tissue matrix with a proteolytic enzyme to produce a desired pliability of the tissue matrix and/or to control the immunogenicity of the tissue matrix. The methods can comprise treatment with alcalase under conditions controlled to produce a desired pliability without unacceptable alteration in collagen structure.

What is claimed is: 
     
         1 . A method for treating a tissue matrix, comprising:
 selecting a tissue;   contacting the tissue with a first solution comprising an effective amount of alcalase under conditions including an incubation time in the first solution having an alcalase activity selected to produce an increase in pliability of the tissue without producing significant collagen degradation to produce an alcalase-treated tissue; and   treating the alcalase-treated tissue with a second solution to decellularize the alcalase-treated tissue to produce an acellular tissue matrix.   
     
     
         2 . The method of  claim 1 , wherein the tissue is a non-primate tissue. 
     
     
         3 . The method of  claim 1 , wherein the tissue is a porcine tissue. 
     
     
         4 . The method of  claim 1 , wherein the first solution comprises alcalase with an activity of 1×10 −6  Anson units/mL to 0.015 Anson units/mL. 
     
     
         5 . The method of  claim 1 , wherein the first solution comprises alcalase with an activity of 1×10 −6  Anson units/mL to 1.5×10 −3  Anson units/mL. 
     
     
         6 . The method of  claim 1 , wherein the first solution comprises alcalase with an activity of about 2×10 −5  Anson units/mL to about 4×10 −5  Anson units/mL. 
     
     
         7 . The method of  claim 1 , further comprising packaging the tissue matrix. 
     
     
         8 . The method of  claim 7 , further comprising sterilizing the tissue matrix. 
     
     
         9 . The method of  claim 1 , wherein the tissue is contacted with alcalase under conditions to produce reductions in the drape value of or at least 30%. 
     
     
         10 . The method of  claim 1 , wherein the tissue is contacted with alcalase under conditions to produce reductions in the drape value of or at least 40%. 
     
     
         11 . The method of  claim 1 , wherein the tissue is contacted with alcalase under conditions to produce reductions in the drape value of or at least 50%. 
     
     
         12 . The method of  claim 1 , wherein the tissue is contacted with alcalase under conditions to produce reductions in the drape value of or at least 60%. 
     
     
         13 . The method of  claim 1 , wherein the tissue is contacted with alcalase under conditions to produce a drape value of 0.2-0.4. 
     
     
         14 . The method of  claim 1 , wherein the pliability is measured with a drape test comprising placing the acellular tissue matrix of a known circular area on top of a circular pedestal having a known diameter and dividing the projected area of the acellular tissue matrix after it drapes over the pedestal by the original area of the tissue matrix circle to determine the drape value. 
     
     
         15 . The method of  claim 1 , wherein the tissue comprises adipose tissue. 
     
     
         16 . The method of  claim 1 , wherein the tissue comprises small intestine. 
     
     
         17 . The method of  claim 1 , wherein the tissue comprises skeletal muscle. 
     
     
         18 . The method of  claim 1 , wherein the tissue comprises bladder tissue. 
     
     
         19 . The method of  claim 1 , wherein the second solution comprises a detergent. 
     
     
         20 . The method of  claim 1 , wherein the tissue is in the form of a sheet.