Bioactive scaffolds

What is claimed is: 
     
       1. A tissue scaffold comprising mammalian cells which have colonized the scaffold, wherein the mammalian cells are transgenic cells in that they comprise a first transgenic bioactive molecule, and wherein the transgenic cells are treated, after colonization of the scaffold, so that they are unable to undergo mitosis. 
     
     
       2. The tissue scaffold of  claim 1 , wherein the transgenic cells are killed by freezing then thawing the transgenic cells. 
     
     
       3. The tissue scaffold of  claim 1 , wherein the tissue scaffold is lyophilized. 
     
     
       4. The tissue scaffold of  claim 2 , wherein the tissue scaffold is lyophilized after the transgenic cells have been killed by freezing then thawing. 
     
     
       5. The tissue scaffold of  claim 1 , wherein the first transgenic bioactive molecule is a bone growth factor, a nerve growth factor, a cartilage growth factor, a growth factor affecting wound healing, or a growth factor affecting tissue repair. 
     
     
       6. The tissue scaffold of  claim 5 , wherein the first transgenic bioactive molecule is a platelet-derived growth factor (PDGF), a vascular endothelial growth factor (VEGF), an epidermal growth factor (EGF), a basic fibroblast growth factor (FGF), an insulin-like growth factor (IGF), an endothelial derived growth supplement (EDGS), a keratinocyte growth factor (KCF), an osteogenin, a skeletal growth factor (SGF), a bone-derived growth factor (BDGFs), a retinoid, a growth hormone (GH), a bone morphogenic protein (BMP), a transcription factor, a member of the hedgehog family, or a transferrin. 
     
     
       7. The tissue scaffold of  claim 5 , wherein the first transgenic bioactive molecule is a bone morphogenic protein (BMP), a TGF-β, or an insulin-like growth factor (IGF). 
     
     
       8. The tissue scaffold of  claim 5 , wherein the first transgenic bioactive molecule is a PDGFβ or an IGF-1. 
     
     
       9. The tissue scaffold of  claim 1 , wherein the mammalian cells further comprise a second transgenic bioactive molecule. 
     
     
       10. The tissue scaffold of  claim 1 , wherein the mammalian cells are human cells. 
     
     
       11. The tissue scaffold of  claim 1 , wherein the cells are nerve cells, epidermal cells, dermal cells, periosteal cells, epithelial cells, endothelial cells, tendon cells, embryonic stem cells, adult stem cells, osteoblasts, myoblasts, chondrocytes, or fibroblasts. 
     
     
       12. The tissue scaffold of  claim 1 , wherein the scaffold is derived from a vertebrate. 
     
     
       13. The tissue scaffold of  claim 1 , wherein the scaffold is artificial. 
     
     
       14. The tissue scaffold of  claim 13 , wherein the scaffold comprises at least one of collagen, alginate, chitosan, poly (paradioxanone), poly(lactic acid), poly(glycolic acid), or a copolymer of poly(lactic acid) and poly(glycolic acid). 
     
     
       15. The tissue scaffold of  claim 1 , wherein the scaffold further comprises additional vertebrate cells seeded onto the scaffold, wherein the additional vertebrate cells are alive. 
     
     
       16. The tissue scaffold of  claim 15 , wherein the additional vertebrate cells do not express a transgenic bioactive molecule. 
     
     
       17. The tissue scaffold of  claim 15 , wherein the additional vertebrate cells express an additional transgenic bioactive molecule. 
     
     
       18. The tissue scaffold of  claim 17 , wherein the additional transgenic bioactive molecule is a protein or a nucleic acid. 
     
     
       19. The tissue scaffold of  claim 17 , wherein the additional transgenic bioactive molecule is a protein. 
     
     
       20. The tissue scaffold of  claim 19 , wherein the additional transgenic bioactive molecule is an enzyme, a cytokine, a marker protein or an antibody. 
     
     
       21. The tissue scaffold of  claim 17 , wherein the additional transgenic bioactive molecule is a nucleic acid. 
     
     
       22. The tissue scaffold of  claim 21 , wherein the nucleic acid is an RNAi molecule, a ribozyme, as antisense molecule, or an aptamer. 
     
     
       23. The tissue scaffold of  claim 17 , wherein the additional transgenic bioactive molecule is constitutively expressed. 
     
     
       24. The tissue scaffold of  claim 17 , wherein the additional transgenic bioactive molecule is operably linked to an inducible promoter. 
     
     
       25. The tissue scaffold of  claim 15 , wherein the additional vertebrate cells are capable of mitosis. 
     
     
       26. A method of tissue repair in a mammal, the method comprising implanting the tissue scaffold of  claim 1  into the tissue in the mammal, wherein the tissue is bone, cartilage, nerve or tendon tissue. 
     
     
       27. A method of delivering a first transgenic bioactive molecule to a tissue of a mammal, the method comprising implanting the tissue scaffold of  claim 1  into the mammal in or adjacent to the tissue. 
     
     
       28. A method of making the tissue scaffold of  claim 1 , the method comprising
 seeding a scaffold with mammalian vertebrate cells comprising a transgene encoding a first bioactive molecule, 
 incubating the scaffold under conditions and for a time sufficient for the mammalian cells to colonize the scaffold and express the first transgenic bioactive molecule, and 
 treating the mammalian cells colonizing the scaffold such that the cells are unable to undergo mitosis. 
 
     
     
       29. the method of  claim 28 , wherein the mammalian vertebrate cells colonizing the scaffold are treated by freezing and thawing. 
     
     
       30. The method of  claim 29 , wherein the scaffold is lyophilized after the step of freezing and thawing the cells. 
     
     
       31. The method of  claim 28 , wherein the scaffold is subsequently seeded with additional vertebrate cells, wherein the additional vertebrate cells are alive. 
     
     
       32. The method of  claim 28 , wherein the vertebrate cells are human cells. 
     
     
       33. The method of  claim 31 , wherein the additional vertebrate cells are human cells.