Flat microfibers as matrices for cell growth

Abstract

The present invention relates to culturing cells utilizing a matrix of microfibrillated thermoplastic polymeric materials. More specifically, the present invention relates to a method of culturing cells. In addition, the invention relates to a microfibrillated article for culturing cells dispersed in a cell culture medium. The matrix of thermoplastic polymeric materials for culturing cells of this invention finds use in tissue engineering and wound healing applications.

1 . A method of culturing cells comprising: 
 providing a matrix of oriented, thermoplastic, substantially rectangular microfibers having an average effective diameter less than 20 micrometers, the matrix dispersed in a cell culture medium; and    inoculating the matrix with cells.    
   
   
       2 . The method of  claim 1 , wherein the microfibers have an average effective diameter of from 0.0 1 micrometers to 10 micrometers.  
   
   
       3 . The method of  claim 1 , wherein the microfibers have a transverse aspect ratio of 1.5:1 to 20:1.  
   
   
       4 . The method of  claim 3 , wherein the microfibers have a transverse aspect ratio of from 3:1 to 20:1.  
   
   
       5 . The method of  claim 1 , wherein the microfibers have a cross-sectional area of 0.05 to 3.0 μm 2 .  
   
   
       6 . The method of  claim 1 , wherein the microfibers have a surface area greater than 0.25 m 2 /gram.  
   
   
       7 . The method of  claim 1 , wherein the microfibers have a tensile modulus of at least 5 GPa.  
   
   
       8 . The method of  claim 1 , wherein the oriented thermoplastic microfibers comprise an aliphatic polyester.  
   
   
       9 . The method of  claim 8 , wherein the aliphatic polyester is selected from poly(butylenes succinate) homopolymer, poly(butylene adipate) homopolymer, poly(butylenes adipate-succinate) copolymer, poly(ethylenesuccinate-adipate) copolymer, poly(ethylene adipate) homopolymer, polylactide, polydioxanone, polycaprolactone, poly(3-hydroxybutyrate), poly(3-hydroxystearate), polyglycolide, poly(oxyethylene glycolate), copolymers of polylactide, and copolymers of polyglycolide.  
   
   
       10 . The method of  claim 8 , wherein the microfibers comprise a blend of two or more aliphatic polyesters.  
   
   
       11 . The method of  claim 1 , wherein the oriented thermoplastic microfibers comprise a polyolefin.  
   
   
       12 . The method of  claim 11 , wherein the polyolefin is selected from polypropylene homopolymer, polyethylene homopolymer, copolymers of polyethylene, copolymers of polypropylene, and blends comprising polypropylene.  
   
   
       13 . The method of  claim 11 , wherein the microfibers comprise a blend of two or more polyolefins.  
   
   
       14 . The method of  claim 8 , wherein the microfibers are biodegradable.  
   
   
       15 . The method of  claim 8 , wherein the microfibers are bioabsorbable.  
   
   
       16 . The method of  claim 1 , wherein the cells are selected from mammalian cells, bacteria and fungi.  
   
   
       17 . The method of  claim 16 , wherein the cells are fibroblasts.  
   
   
       18 . An article for culturing cells comprising a matrix of oriented, thermoplastic, substantially rectangular microfibers having an average effective diameter less than 20 micrometers, the matrix dispersed in a cell culture medium.  
   
   
       19 . The article of  claim 18 , wherein the matrix comprises a microfibrillated article.  
   
   
       20 . The article of  claim 18 , wherein the microfibers are integral to a depth of 10 micrometers or greater in a microfibrillated article.  
   
   
       21 . The article of  claim 18 , wherein the cell culture medium further comprises cells.  
   
   
       22 . The article of  claim 19 , wherein the microfibers are integral to a thermoplastic polymeric film having a microfibrillated surface.  
   
   
       23 . The article of  claim 19 , wherein the article comprises a film having a microfibrillated morphology throughout the thickness of the film.  
   
   
       24 . A tissue scaffold comprising a matrix of oriented, thermoplastic, substantially rectangular microfibers having an average effective diameter less than 20 micrometers dispersed within a cell culture medium.  
   
   
       25 . A multi-well plate comprising a plurality of wells comprising a matrix of oriented, thermoplastic, substantially rectangular microfibers having an average effective diameter less than 20 micrometers dispersed within a cell culture medium.