Preparation of agarose coated, solid agarose beads containing secretory cells

Abstract

Biological agents such as secretory cells are encapsulated in a hydrophilic gel made of agarose or collagen-agarose and gelatin sponge-agarose combinations. In a preferred embodiment, semi-solid beads are formed from a suspension containing collagen, agarose and secretory cells such as pancreatic islets, the collagen is polymerized to form solid, agarose-collagen beads and the solid beads are coated with agarose. Coating is preferably by rolling the solid beads in about 5-10% agarose, contacting the rolled beads with mineral oil and washing oil from the beads. Beads containing secretory cells can be transplanted into a mammal to treat a condition caused by impaired secretory cell function.

1. A method for preparing an agarose coated, solid agarose-collagen bead which contains secretory cells, comprising:
 (a) suspending secretory cells in a collagen containing solution,    (b) adding agarose to said solution,    (c) forming a semi-solid bead of said collagen, agarose, and secretory cells,    (d) polymerizing collagen in said semisolid bead to form a solid, agarose-collagen bead containing secretory cells, and    (e) coating said solid, agarose-collagen bead containing secretory cells with agarose.    
     
     
       2. The method of  claim 1 , wherein said secretory cells are contained in pancreatic islets. 
     
     
       3. The method of  claim 2 , wherein said pancreatic islets are human pancreatic islets, bovine pancreatic islets, rat pancreatic islets or porcine pancreatic islets. 
     
     
       4. The method of  claim 3 , wherein said pancreatic islets are human pancreatic islets. 
     
     
       5. The method of  claim 1 , wherein said secretory cells are contained in from about 50,000 to about 700,000 pancreatic islets. 
     
     
       6. An agarose coated, solid agarose-collagen bead containing secretory cells prepared by the process of  claim 1 . 
     
     
       7. The agarose coated, solid agarose-collagen bead of  claim 6 , wherein said secretory cells are contained in pancreatic islets. 
     
     
       8. The agarose coated, solid agarose-collagen bead of  claim 6  wherein said pancreatic islets are human pancreatic islets, bovine pancreatic islets, rat pancreatic islets or porcine pancreatic islets. 
     
     
       9. The agarose coated, solid agarose-collagen bead of  claim 8  wherein said pancreatic islets are human pancreatic islets. 
     
     
       10. The agarose coated, solid agarose collagen bead of  claim 7 , comprising from about 50,000 to 700,000 islets. 
     
     
       11. Method for treating a mammal having a condition caused by impaired secretory cell function, comprising:
 transplanting into said mammal a therapeutically effective amount of the agarose coated, solid agarose-collagen bead of  claim 6 .    
     
     
       12. The method of  claim 11 , wherein said condition is insulin dependent diabetes. 
     
     
       13. The method of  claim 12 , wherein said bead contains cells derived from a pancreatic islet. 
     
     
       14. The method of  claim 13 , wherein said pancreatic islet is a human pancreatic islet. 
     
     
       15. The method of  claim 13 , wherein said pancreatic islet is a bovine pancreatic islet. 
     
     
       16. The method of  claim 13 , wherein said pancreatic islet is a porcine pancreatic islet. 
     
     
       17. The method of  claim 11 , wherein said bead is placed in the peritoneal cavity of said mammal. 
     
     
       18. A composition of matter comprising a sample of secretory cells in a bead which comprises agarose, wherein said bead is coated with a solution comprising from  5 %  to  10   %  agarose.    
     
     
       19. The composition of matter of  claim 18 , wherein said secretory cells comprise pancreatic islet cells or pancreatic islets.  
     
     
       20. The composition of matter of  claim 19 , wherein said pancreatic islet cells or pancreatic islets comprise human, porcine, or bovine pancreatic islet cells or pancreatic islets.  
     
     
       21. The composition of matter of  claim 19 , comprising  1000  pancreatic islets.  
     
     
       22. The composition of matter of  claim 18 , wherein said bead is coated with a solution containing  5 %  agarose.    
     
     
       23. A composition of matter comprising a sample of secretory cells entrapped in a bead which comprises from  0 . 5 %  to  5   %  agarose, wherein said bead is coated with a coating of agarose.    
     
     
       24. The composition of matter of  claim 23 , wherein said secretory cells comprise pancreatic islet cells or pancreatic islets.  
     
     
       25. The composition of matter of  claim 24 , wherein said pancreatic islet cells or pancreatic islets are human, bovine, or porcine pancreatic islet cells or pancreatic islets.  
     
     
       26. The composition of matter of  claim 23 , wherein said Bead comprises about  1 %  agarose.    
     
     
       27. The composition of matter of  claim 23 , wherein said Coating comprises about  5 %  agarose.    
     
     
       28. The composition of matter of  claim 24  comprising  1000  pancreatic islets.  
     
     
       29. A method for treating a subject having a condition caused by impaired functioning of secretory cells, comprising transplanting an amount of the composition of matter of  claim 18  sufficient to alleviate said condition to said subject.  
     
     
       30. The method of  claim 29 , wherein said condition is diabetes and said secretory cells comprise pancreatic islets or pancreatic islet cells.  
     
     
       31. A method for treating a subject having a condition caused by impaired functioning of secretory cells, comprising transplanting an amount of the composition of matter of  claim 23  sufficient to alleviate said condition to said subject.  
     
     
       32. The method of  claim 31 , wherein said condition is Insulin dependent diabetes and said secretory cells comprise pancreatic islet cells or pancreatic islets.  
     
     
       33. The method of  claim 32 , wherein said pancreatic islet cells or pancreatic islets are human, bovine, or porcine pancreatic islet cells or pancreatic islets.  
     
     
       34. The method of  claim 31 , comprising transplanting said amount of the composition of matter to the intraperitoneal cavity of said subject.  
     
     
       35. A composition of matter produced by combining a sample of secretory cells and a solution which contains from  0 . 5 %  to  5   %  agarose to form a suspension, treating said suspension to form a bead, and coating said bead with agarose.    
     
     
       36. The composition of matter of  claim 35 , wherein said secretory cells comprise pancreatic islet cells or pancreatic islets.  
     
     
       37. The composition of matter of  claim 36 , wherein said pancreatic islet cells or pancreatic islets are human, bovine or porcine pancreatic islet cells or pancreatic islets.  
     
     
       38. The composition of matter of  claim 35 , wherein said solution contains about  1 %  agarose.    
     
     
       39. The composition of matter of  claim 35 , wherein said bead is coated with a solution containing about  5 %  agarose.    
     
     
       40. The composition of matter of  claim 35 , comprising  1000  pancreatic islets.  
     
     
       41. The composition of matter of  claim 35 , wherein said coating comprises from about  5 %  to  10   %  agarose.    
     
     
       42. A composition of matter comprising a sample of secretory cells contained in a bead which comprises agarose and collagen, wherein said bead is coated with a coating of agarose.  
     
     
       43. The composition of matter of  claim 42 , wherein said secretory cells comprise pancreatic islet cells or pancreatic islets.  
     
     
       44. The composition of matter of  claim 42 , wherein said pancreatic islet cells or pancreatic islets comprise human, porcine, or bovine pancreatic islet cells or pancreatic islets.  
     
     
       45. The composition of matter of  claim 42 , comprising  1000  pancreatic islets.  
     
     
       46. The composition of matter of  claim 42 , wherein said bead is coated with a solution comprising from  5 %  to  10   %  agarose.    
     
     
       47. A method for treating a subject having a condition caused by impaired functioning of secretory cells, comprising transplanting an amount of the composition of matter of  claim 42  sufficient to alleviate said condition to said subject.  
     
     
       48. The method of  claim 47 , wherein said condition is diabetes and said secretory cells comprise pancreatic islets or pancreatic islet cells.  
     
     
       49. A method for preserving secretory cells, comprising:
 ( a )  forming an agarose coated, agarose containing bead, or an agarose coated bead containing both agarose and collagen, with secretory cells entrapped therein, and,      ( b )  maintaining the secretory cell containing bead to preserve the secretory cells therein.