Placenta-derived matrix and methods of preparing and use thereof

Abstract

The invention relates to placenta-derived matrix, methods of preparing, and methods of use thereof. The invention also relates to methods of culturing cells, delivering cells, promoting differentiation of stem cells or tissue-specific progenitor cells, and repairing, replacing, regenerating, filling, reducing or inhibiting scarring of defects using the same. The invention further relates to methods of coating placenta-derived matrix on a surface or injecting the placenta-derived matrix into a site of interest.

What is claimed: 
     
         1 . A method of preparing a surface of a substrate coated with a placental-derived sponge structure, said method comprising:
 (a) devitalizing a placenta tissue to produce a devitalized placenta tissue;   (b) digesting the devitalized placenta tissue in a digestion solution having a pepsin and an acid to produce a placenta-derived matrix;   (c) adjusting pH of the placenta-derived matrix from step (b) to a basic pH of 8.0 to 11.0 to irreversibly inactivate the pepsin;   (d) adjusting the pH of the placenta-derived matrix from step (c) to a neutral pH of 7.0 to 7.2 to prepare a neutralized placenta-derived matrix; and   (e) freeze-drying the neutralized placenta-derived matrix onto a surface of a substrate to coat the surface of the substrate with a placenta-derived sponge structure.   
     
     
         2 . The method of  claim 1 , wherein an average void volume of the sponge structure is from 10% to 95%. 
     
     
         3 . The method of  claim 1 , wherein the DNA quantity in the devitalized placenta tissue is reduced at least by 90% compared to the DNA quantity in the placenta tissue prior to step (a). 
     
     
         4 . The method of  claim 1 , further comprising gelling the sponge structure on the surface. 
     
     
         5 . A placenta-derived matrix comprising a devitalized placenta tissue, wherein the placenta-derived matrix has a pH of 8.0 or more. 
     
     
         6 . The placenta-derived matrix of  claim 5 , wherein the placenta-derived matrix is a hydrogel. 
     
     
         7 . The placenta-derived matrix of  claim 5 , wherein the placenta-derived matrix comprises no more than 200 ng DNA per mg of the dry weight of placenta-derived matrix. 
     
     
         8 . The placenta-derived matrix of  claim 6 , wherein the placenta-derived matrix comprises no more than 200 ng DNA per mg of the dry weight of placenta-derived matrix.