Methods and systems for stiffening of tissue for improved processing

Abstract

Methods and systems for stiffening of tissue are presented to allow improved processing. Solutions including an acid or a base can be contacted with tissue to stiffen one or more components of the tissue. The resulting stiffened tissue can be used in the creation of wound treatment devices.

1 . A device for treating a fistula, comprising:
 an elongated, cylindrical tissue matrix composition that comprises an acellular tissue matrix that is formed from a tissue that has been treated with a solution including an acid or base to stiffen the tissue and has been treated with a protease to remove immunogenic materials from the elongated, cylindrical tissue matrix,   wherein structural integrity of collagen in the tissue matrix is undamaged.   
     
     
         2 . The device of  claim 1 , wherein the solution has not caused substantial irreversible denaturation of the tissue. 
     
     
         3 . The device of  claim 1 , wherein the tissue is dermal tissue. 
     
     
         4 . The device of  claim 1 , wherein the tissue is at least one of fascia, pericardial tissue, dura, umbilical cord tissue, cartilage, tendon, reticulate, placental tissue, cardiac valve tissue, ligament tissue, tendon tissue, arterial tissue, venous tissue, neural connective tissue, urinary bladder tissue, ureter tissue, and small-intestine submucosa. 
     
     
         5 . The device of  claim 1 , wherein the solution comprises acetic acid at a concentration of 0.1 M or less. 
     
     
         6 . The device of  claim 1 , wherein the solution has a pH value between 2 and 3.5. 
     
     
         7 . The device of  claim 1 , wherein an elongated shape of the elongated, cylindrical tissue matrix has a length of at least 1 centimeter. 
     
     
         8 . The device of  claim 7 , wherein the elongated shape has a length of at least 3 centimeters. 
     
     
         9 . The device of  claim 8 , wherein the elongated shape has a length of at least 5 centimeters. 
     
     
         10 . The device of  claim 1 , wherein a cylindrical shape of the elongated, cylindrical tissue matrix has a diameter in a range of 1 to 5 millimeters. 
     
     
         11 . The device of  claim 1 , wherein a decellularization process has been performed on the tissue. 
     
     
         12 . The device of  claim 11 , wherein the decellularization process is performed prior to contacting the tissue with the solution to stiffen the tissue. 
     
     
         13 . The device of  claim 11 , wherein the decellularization process is performed after contacting the tissue with the solution to stiffen the tissue. 
     
     
         14 . The device of  claim 1 , wherein the protease comprises a subtilisin-like serine protease, a trypsin-like serine protease, or a thiol protease. 
     
     
         15 . The device of  claim 1 , wherein the protease has been contacted with the tissue under conditions that result in a tissue having an improved biologic response when implanted in vivo. 
     
     
         16 . The device of  claim 15 , wherein the improved biologic response comprises reduced inflammation as compared to a tissue not treated with the enzyme. 
     
     
         17 . The device of  claim 15 , wherein the improved biologic response comprises improved cellular ingrowth. 
     
     
         18 . The device of  claim 1 , wherein the tissue has been treated with an enzyme comprising at least one of bromelain, papain, ficin, actinidin, a subtilisin-like serine protease, trypsin, or combinations thereof. 
     
     
         19 . The device of  claim 1 , wherein the tissue has been treated with a dispase. 
     
     
         20 . A method of treating a tissue site comprising:
 implanting the device of  claim 1  in or on the tissue site.