Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
134 words
An in vitro process for generating implants or grafts of collagenous, connective, or vascular tissue which are xenogeneic to a human recipient comprising decellularizing a natural tissue to produce a tissue matrix, the tissue matrix is next washed to remove cellular antigens, or extracellular antigens, or both, followed by treatment of the tissue matrix with adhesion factors comprised of fibronectin and heparin effective to promote attachment thereto of fibroblast cells immunologically acceptable to the implant or graft recipient, next the tissue matrix is treated with adhesion factor and is repopulated by incubating the matrix in the presence of the fibroblast cells and fibroblast growth factor until such cellular repopulation provides a vitalized tissue histologically similar to the corresponding natural tissue, and wherein the implant tissue generated is mechanically, biochemically and immunologically suitable for implantation.
Claim 2
Dependent Claim
134 words
An in vitro process for generating implants or grafts of collagenous, connective, or vascular tissue which are xenogeneic to a human recipient comprising decellularizing a natural tissue to produce a tissue matrix, the tissue matrix is next washed to remove cellular antigens, or extracellular antigens, or both, followed by treatment of the tissue matrix with adhesion factors comprised of fibronectin and heparin effective to promote attachment thereto of fibroblast cells immunologically acceptable to the implant or graft recipient, next the tissue matrix is treated with adhesion factor and is repopulated by incubating the matrix in the presence of the fibroblast cells and fibroblast growth factor until such cellular repopulation provides a vitalized tissue histologically similar to the corresponding natural tissue, and wherein the implant tissue generated is mechanically, biochemically and immunologically suitable for implantation.
Claim 3
Dependent Claim
16 words
The process of claim 1 wherein the fibronectin comprises human plasma fibronectin or human tissue fibronectin.
Claim 4
Dependent Claim
12 words
The process of claim 2 wherein the natural tissue is collagenous tissue.
Claim 5
Dependent Claim
12 words
The process of claim 2 wherein the natural tissue is connective tissue.
Claim 6
Dependent Claim
14 words
The process of claim 3 wherein the fibroblast cells are cultured human fibroblast cells.
Claim 7
Dependent Claim
22 words
The process of claim 5 wherein the natural tissue is heart valve tissue, and wherein the repopulation cells are human fibroblast cells.
Claim 8
Dependent Claim
23 words
The process of claim 1 further comprising the step of cryopreserving the tissue matrix at a stage prior to the cellular repopulation step.
Claim 9
Dependent Claim
26 words
The process of claim 4 wherein the natural tissue is decellularized by treatments including treatment with nucleases so as to limit generation of new immunological sites.
Claim 10
Dependent Claim
28 words
The process of claim 1 wherein the heparin adheres fibronectin to portions of the tissue matrix, and wherein the fibroblast-growth factor is basic human recombinant fibroblast growth factor.
Claim 11
Dependent Claim
16 words
The process of claim 9 wherein the natural tissue is aortic or pulmonary heart valve tissue.
Claim 12
Dependent Claim
12 words
The process of claim 1 wherein the fibroblast cells are autogenous cells.
Claim 13
Dependent Claim
12 words
The process of claim 1 wherein the fibroblast cells are allogenous cells.
Claim 14
Dependent Claim
15 words
The process of claim 1 wherein the fibroblast cells are derived from stable cell lines.
Claim 15
Dependent Claim
21 words
The process of claim 1 wherein the fibroblast cells are modified genetically by techniques of stable transfection with exogenous genetic material.
Claim 16
Dependent Claim
22 words
The process of claim 1 wherein the fibroblast cells are of human origin and are modified to be substantially non-immunogenic upon implantation.
Claim 17
Dependent Claim
20 words
The process of claim 1 wherein the fibroblast cells are of human origin and are modified to express specific proteins.
Claim 18
Dependent Claim
65 words
The process of claim 1 wherein the tissue is of porcine or bovine origin, the adhesion matrix factor comprises purified fibronectin and heparin, and wherein the repopulating cells are human fibroblast cells in the presence of effective amounts of basic or acid fibroblast growth factor and the implant tissue produced is a xenogeneic implant substantially free of adverse immunological response upon implantation into a human.
Claim 19
Dependent Claim
21 words
The process of claim 1 wherein the decellularization step comprises treating the tissues with a low ionic strength solution and nucleases.
Claim 20
Dependent Claim
33 words
The process of claim 18 wherein the low ionic strength solution of nucleases includes at least one member selected from the group consisting of RNAase A, DNAase I, EcoR I and Hind III.
Claim 21
Dependent Claim
116 words
The process of claim 1 wherein the natural tissue is collagenous tissue; the tissue is decellularized by treatment with a low ionic strength solution and DNAase I and RNAase A, effective to eliminate native cells and provide a tissue matrix of limited immunogenicity; and the tissue matrix is treated with an amount of a buffered solution containing fibronectin and heparin sulfate effective to provide sites associated with the tissue matrix which facilitate fibroblast cell attachment thereto; and wherein the tissue matrix is repopulated by incubating it together with fibroblast cells of human origin in the presence of an amount of fibroblast growth factor, effective to facilitate cell growth and repopulate the tissue matrix with fibroblast cells.