US2007269476A1PendingUtilityA1

Engineered extracellular matrices control stem cell behavior

52
Assignee: VOYTIK-HARBIN SHERRY LPriority: May 16, 2006Filed: May 16, 2006Published: Nov 22, 2007
Est. expiryMay 16, 2026(expired)· nominal 20-yr term from priority
Inventors:Sherry L. Voytik-HarbinBeverly Z. Waisner
C12N 2533/90C12N 2533/70C12N 2533/54C12N 5/0667C12N 5/0663C12N 5/0656A61L 27/3834A61L 27/3817A61L 27/24A61K 35/12
52
PatentIndex Score
0
Cited by
0
References
0
Claims

Abstract

A composition for culturing stem cells is provided. The composition comprises an engineered purified collagen based matrix that has been formed under controlled conditions to have the desired microstructure and mechanical properties. The engineered purified collagen based matrix compositions of the present invention can be used alone or in combination with cells as a tissue graft construct to enhance the repair of damaged or diseased tissues

Claims

exact text as granted — not AI-modified
1 . A composition for supporting stem cells, said composition comprising
 a synthetic three dimensional matrix comprised of collagen fibrils; and   a population of stem cells entrapped within the three dimensional matrix.   
     
     
         2 . The composition of  claim 1  wherein the synthetic three dimensional matrix has a fibril area fraction of about 8% to about 18%. 
     
     
         3 . The composition of  claim 1  wherein the synthetic three dimensional matrix has a fibril area fraction of about 19% to about 26%. 
     
     
         4 . The composition of  claim 1  wherein the synthetic three dimensional matrix has a elastic or linear modulus of about 0.5 kPa to about 24.0 kPa. 
     
     
         5 . The composition of  claim 1  wherein the synthetic three dimensional matrix has a elastic or linear modulus of about 25.6 to about 40.2 kPa. 
     
     
         6 . The composition of  claim 1  wherein said matrix is synthesized by polymerizing a solubilized collagen composition, said solubilized collagen composition comprising said stem cells at a cell density of about 1×10 3  to about 10 5  cells per milliliter. 
     
     
         7 . The composition of  claim 1  wherein the cells are added at a density of about 10 to about 10 3  cells per milliliter. 
     
     
         8 . The composition of  claim 1  wherein the fibril area fraction of the three dimensional matrix is about 7.7% to about 25%, and the three dimensional matrix further comprises exogenously added glucose and calcium chloride. 
     
     
         9 . The composition of  claim 8  wherein glucose concentration is about 5.55 mM to about 30 mM and the CaCl 2  concentration is about 0.2267 mM to about 1.8 mM. 
     
     
         10 . The composition of  claim 8  wherein the three dimensional matrix is a three dimensional purified collagen matrix. 
     
     
         11 . An improved method for culturing stem cells said method comprising
 providing a solubilized collagen composition;   adding stem cells at a cell density within two orders of magnitude of the minimum cell number required to maintain cell viability;   polymerizing the collagen composition to form a 3D matrix comprising cells entrapped within a collagen fibril network; and   providing conditions conducive to cell growth.   
     
     
         12 . The method of  claim 11  wherein the cells are added at a density of less than 5×10 4  cells per milliliter. 
     
     
         13 . The method of  claim 12  wherein the cells are added at a density of about 10 to about 10 3  per milliliter. 
     
     
         14 . The method of  claim 11  wherein the step of providing conditions conducive to cell growth comprises the step of implanting the 3D matrix into a host species. 
     
     
         15 . The method of  claim 11  wherein the step of providing conditions conducive to cell growth comprises the step of culturing the cells in vitro. 
     
     
         16 . The method of  claim 11  wherein the solubilized collagen composition comprises collagen derived from a naturally occurring extracellular matrix. 
     
     
         17 . The method of  claim 11  wherein the solubilized collagen composition is prepared from a composition consisting essentially of purified type I collagen. 
     
     
         18 . The method of  claim 11  wherein the solubilized collagen composition is prepared from a composition consisting essentially of purified type I and type III collagen. 
     
     
         19 . The method of  claim 11  further comprising the step of adding glucose and calcium chloride to the solubilized collagen composition prior to the polymerization step. 
     
     
         20 . An improved tissue graft construct comprising
 a synthetic three dimensional matrix comprising collagen fibrils; and   a population of stem cells entrapped within the three dimensional matrix,
 wherein said synthetic three dimensional matrix has a fibril area fraction of about 7.7% to about 25%, has a elastic or linear modulus of about 0.5 to about 40 kPa and further comprises exogenously added source of glucose and calcium chloride. 
   
     
     
         21 . The graft construct of  claim 20  wherein said synthetic three dimensional matrix is formed by
 contacting a source of collagen with an acid selected from the group consisting of hydrochloric acid, acetic acid, formic acid, citric acid, lactic acid, sulfuric acid, ethanoic acid, carbonic acid, nitric acid and phosphoric acid to form an acid treated collagen composition;   solubilizing the acid treated collagen to form a solubilized collagen composition; and   polymerizing the solubilized collagen composition to form said three dimensional matrix comprising collagen fibrils surrounded by an interfibrillar fluid,   wherein said population of stem cells are added to the solubilized composition at a density of less than 10 5  cells per milliliter.   
     
     
         22 . The graft construct of  claim 20  wherein the source of collagen comprises a composition formed from purified type I collagen. 
     
     
         23 . The graft construct of  claim 22  wherein the source of collagen comprises composition formed from purified type I and type III collagen. 
     
     
         24 . The graft construct of  claim 20  wherein the three dimensional matrix is a three dimensional purified collagen matrix. 
     
     
         25 . A method of enhancing the repair of tissues in a warm blooded vertebrate, said method comprising implanting or injecting the construct of  claim 20  into said vertebrate at a site in need of repair. 
     
     
         26 . A method of isolating clonal populations of individual stem cells, said method comprising the steps of
 contacting a 3D matrix with a low density of stem cells wherein said collagen matrix is formed by
 contacting a source of collagen with hydrochloric acid to prepare a solubilized collagen composition; 
 polymerizing the solubilized collagen composition using a final collagen concentration of 1.0 to 3.0 mg/ml, at a pH of about 6.5 to about 7.0, 
 wherein the initial seed population of stem cells ranges from about 10 to about 10 3  cells per milliliter; 
 culturing said seeded stem cells and isolating individual population of stem cells.

Join the waitlist — get patent alerts

Track US2007269476A1 — get alerts on status changes and closely related new filings.

We store only your email — no account needed. See our privacy policy.