Graft materials containing bioactive substances, and methods for their manufacture

Abstract

Described are packaged, sterile medical graft products containing controlled levels of a growth factor such as Fibroblast Growth Factor-2 (FGF-2). Also described are methods of manufacturing medical graft products wherein processing, including sterilization, is controlled and monitored to provide medical graft products having modulated, known levels of a extracellular matrix factor, such as a growth factor, e.g. FGF-2. Preferred graft materials are extracellular matrix materials isolated from human or animal donors, particularly submucosa-containing extracellular matrix materials. Further described are ECM compositions that are or are useful for preparing gels, and related methods for preparation and use.

1 - 105 . (canceled) 
     
     
         106 . A method of preparing an extracellular matrix-derived gel comprising, in order: (i) solubilizing extracellular matrix (ECM) that has not been dialyzed by digestion with an acid protease in an acidic solution to produce a digest solution, (ii) drying the digest solution, and (iii) terminally sterilizing the dried digest. 
     
     
         107 . The method of  claim 106 , further comprising:
 (iv) hydrating and neutralizing the sterilized dried digest to a pH between 7.2 and 7.8 to produce a neutralized digest solution, and (v) gelling the solution at a temperature greater than 25° C.   
     
     
         108 . The method of  claim 106 , wherein the ECM is not terminally sterilized, dialyzed or subjected to a cross-linking process prior to the solubilizing step. 
     
     
         109 . The method of  claim 106 , wherein the digest solution is lyophilized. 
     
     
         110 . The method of  claim 106 , wherein the dried digest is sterilized using radiation, electron beam radiation, or ethylene oxide. 
     
     
         111 . The method of  claim 106 , wherein the ECM is derived from mammalian tissue. 
     
     
         112 . The method of  claim 111 , wherein the mammalian tissue is derived from one of urinary bladder, stomach, liver, or small intestine. 
     
     
         113 . The method of  claim 106 , wherein the ECM is comminuted. 
     
     
         114 . The method of  claim 107 , wherein the neutralized digest solution is maintained at or below 25° C. before gelation. 
     
     
         115 . The method of  claim 106 , wherein the acid protease is pepsin. 
     
     
         116 . The method of  claim 115 , wherein the ECM is solubilized at a pH of 2 or higher, or at a pH between 2 and 4. 
     
     
         117 . The method of  claim 107 , wherein the digest solution is gelled at 30° C. or higher, or at about 37° C. 
     
     
         118 . The method of  claim 107 , further comprising administering the neutralized digest solution to a patient and wherein the gelling takes place in or on the patient. 
     
     
         119 . The method of  claim 118 , wherein the pH of digest solution is raised by mixing the digest solution with a base or a buffer during administration to the patient. 
     
     
         120 . The method of  claim 107 , further comprising integrating one or more of a cell, a drug, a growth factor or an antibiotic into the gel. 
     
     
         121 . The method of  claim 107 , further comprising coating a matrix of a biocompatible scaffold with the solubilized ECM and gelling the matrix. 
     
     
         122 . The method of  claim 121 , wherein the biocompatible scaffold is coated either with the digest solution between the steps of solubilizing the ECM and drying the digest solution or with either the sterilized digest solution or the neutralized digest solution after the step of hydrating the digest solution and before the neutralized digest solution is gelled. 
     
     
         123 . The method of  claim 122 , wherein the biocompatible scaffold comprises a polymer. 
     
     
         124 . The method of  claim 122 , wherein the biocompatible scaffold comprises filaments.