Cross-linked collagen and uses thereof

Abstract

The present invention discloses collagen cross-linked in a micro to non-fibrillar form and at a high concentration. The cross-linked collagen gel has improved volume stability or persistence than collagen cross-linked at a neutral pH. Also disclosed are methods for preparing the inventive cross-linked collagen and using such for augmenting soft tissues in mammals.

1 . A method for preparing cross-linked collagen, comprising:
 obtaining micro to non-fibrillar collagen;   treating the micro to non-fibrillar collagen with a cross-linking agent; and   isolating cross-linked collagen.   
     
     
         2 . The method of  claim 1 , wherein the micro to non-fibrillar collagen is obtained by incubating fibrillar collagen in a suspension or solution of pH 2-5 or pH 9-12. 
     
     
         3 . The method of  claim 2 , wherein the micro to non-fibrillar collagen is obtained by incubating the fibrillar collagen in a suspension or solution of pH 4.2-5.0. 
     
     
         4 . The method of  claim 1 , wherein the concentration of the micro to non-fibrillar collagen is in the range of 3-150 mg/mL. 
     
     
         5 . The method of  claim 4 , wherein the concentration of the micro to non-fibrillar collagen is in the range of 38-52 mg/mL. 
     
     
         6 . The method of  claim 1 , wherein the treating step includes treating the micro to non-fibrillar collagen with the cross-linking agent at pH 2-5 or pH 9-12, followed by treating the micro to non-fibrillar collagen with the cross-linking agent at pH 6-8. 
     
     
         7 . The method of  claim 1 , wherein the cross-linked collagen derives from type I, II, III, IV or V collagen, or a combination thereof. 
     
     
         8 . The method of  claim 7 , wherein the cross-linked collagen derives from telo-containing collagen, atelo-collagen or derivatized collagen, or a combination thereof. 
     
     
         9 . The method of  claim 1 , wherein the cross-linking agent is capable of forming covalent bonds between amino acid residues in the micro to non-fibrillar collagen. 
     
     
         10 . The method of  claim 9 , wherein the cross-linking agent is selected from the group consisting of carbodiimides, polyaldehydes, polysulfones, activated PEGs, epoxides, imidazoles and diisocyanates. 
     
     
         11 . The method of  claim 10 , wherein the cross-linking agent is glutaraldehyde. 
     
     
         12 . The method of  claim 1 , further comprising admixing a local anesthetic agent with the cross-linked collagen. 
     
     
         13 . The method of  claim 12 , wherein the local anesthetic agent is lidocaine. 
     
     
         14 . A method for filling voids and defects and increasing tissue volume in a mammal, comprising administering to a mammal the cross-linked collagen prepared according to the method of  claim 1 . 
     
     
         15 . The method of  claim 14 , wherein the cross-linked collagen is administered by intradermal or subcutaneous injection. 
     
     
         16 . Cross-linked collagen prepared according to the method of  claim 1 . 
     
     
         17 . The cross-linked collagen of  claim 16 , wherein the number of free hydroxy lysine and lysine residues per 1000 amino acid residues in the cross-linked collagen is in the range of 22-32. 
     
     
         18 . The cross-linked collagen of  claim 17 , wherein the number of free hydroxy lysine and lysine residues per 1000 amino acid residues in the cross-linked collagen is in the range of 24-29. 
     
     
         19 . The cross-linked collagen of  claim 16 , wherein the cross-linked collagen is in a gel but not fibrous state. 
     
     
         20 . The cross-linked collagen of  claim 19 , wherein the cross-linked collagen locks water in the gel and does not disperse like a fibrous collagen suspension. 
     
     
         21 . The cross-linked collagen of  claim 19 , wherein the cross-linked collagen in the gel state maintains its shape in vivo better than cross-linked collagen in a fibrous state. 
     
     
         22 . The cross-linked collagen of  claim 19 , wherein the fibers of the cross-linked collagen are smaller than those of fibrous collagen cross-linked at a neutral pH. 
     
     
         23 . A composition comprising the cross-linked collagen of  claim 16  and a local anesthetic agent admixed with the cross-linked collagen. 
     
     
         24 . The composition of  claim 23 , wherein the local anesthetic agent is lidocaine. 
     
     
         25 . A packaged product, comprising a syringe and a needle, wherein the syringe is loaded with the cross-linked collagen of  claim 16 . 
     
     
         26 . Cross-linked collagen, comprising:
 micro to non-fibrillar collagen; and   a cross-linking agent,   wherein the micro to non-fibrillar collagen is cross-linked by the cross-linking agent.   
     
     
         27 . The cross-linked collagen of  claim 26 , wherein the cross-linked collagen derives from type I, II, III, IV or V collagen, or a combination thereof. 
     
     
         28 . The cross-linked collagen of  claim 27 , wherein the cross-linked collagen derives from telo-containing collagen, atelo-collagen or derivatized collagen, or a combination thereof. 
     
     
         29 . The cross-linked collagen of  claim 26 , wherein the cross-linking agent is capable of forming covalent bonds between amino acid residues in the micro to non-fibrillar collagen. 
     
     
         30 . The cross-linked collagen of  claim 29 , wherein the cross-linking agent is selected from the group consisting of carbodiimides, polyaldehydes, polysulfones, activated PEGs, epoxides, imidazoles and diisocyanates. 
     
     
         31 . The cross-linked collagen of  claim 30 , wherein the cross-linking agent is glutaraldehyde. 
     
     
         32 . The cross-linked collagen of  claim 26 , wherein the number of free hydroxy lysine and lysine residues per 1000 amino acid residues in the cross-linked collagen is in the range of 22-32. 
     
     
         33 . The cross-linked collagen of  claim 32 , wherein the number of free hydroxy lysine and lysine residues per 1000 amino acid residues in the cross-linked collagen is in the range of 24-29. 
     
     
         34 . The cross-linked collagen of  claim 26 , wherein the cross-linked collagen is in a gel but not fibrous state. 
     
     
         35 . The cross-linked collagen of  claim 34 , wherein the cross-linked collagen locks water in the gel and does not disperse like a fibrous collagen suspension. 
     
     
         36 . The cross-linked collagen of  claim 34 , wherein the cross-linked collagen in the gel state maintains its shape in vivo better than cross-linked collagen in the fibrous state. 
     
     
         37 . The cross-linked collagen of  claim 34 , wherein the fibers of the cross-linked collagen are smaller than those of fibrous collagen cross-linked at a neutral pH. 
     
     
         38 . A composition comprising the cross-linked collagen of  claim 26  and a local anesthetic agent admixed with the cross-linked collagen. 
     
     
         39 . The composition of  claim 38 , wherein the local anesthetic agent is lidocaine. 
     
     
         40 . A packaged product, comprising a syringe and a needle, wherein the syringe is loaded with the cross-linked collagen of  claim 26 . 
     
     
         41 . A method for filling voids and defects and increasing tissue volume in a mammal, comprising administering to a mammal the cross-linked collagen of  claim 26 . 
     
     
         42 . The method of  claim 41 , wherein the cross-linked collagen is administered by intradermal or subcutaneous injection.