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AssigneesMassachusetts Institute of Technology, Children's Hospital, Inc.
InventorsJoseph P. Vacanti, Charles A. Vacanti, Robert S. Langer
Estimating the term…
Methods and artificial matrices for the growth and implantation of cartilaginous structures and surfaces are disclosed. In the preferred embodiments, chondrocytes are grown on biodegradable, biocompatible fibrous polymeric matrices. Optionally, the cells are proliferated in vitro until an adequate cell volume and density has developed for the cells to survive and proliferate in vivo. One advantage of the matrices is that they can be cast or molded into a desired shape, on an individual basis, so that the final product closely resembles a patient's own ear or nose. Alternatively, flexible matrices can be used which can be manipulated at the time of implantation, as in a joint, followed by remodeling through cell growth and proliferation in vivo. The cultured cells can also be maintained on the matrix in a nutrient media for production of bioactive molecules such as angiogenesis inhibiting factor.
A method for making a cartilaginous structure comprising
The method of claim 10 wherein the polymer is selected from the group consisting of on histologic evaluation. In vitro, all polymer fibers (controls and experimentals) began to dissolve by day 27. On gross and histologic examination using Hematoxylin and Eosin stain, none of the 16 specimens designated as controls displayed any evidence of cartilage. In contrast, 18 of 20 specimens in the experimental group showed evidence of cartilage formation grossly, as well as histologically using Hematoxylin and Eosin stain. Histologic examination of the implants removed at day 8 showed the fibers were imbedded in fibrous tissue with evidence of a mild inflammatory response consisting of infiltrates of polymorphonuclear leukocytes and giant cells, and isolated "nests" of cartilage. During the time intervals to day 18 and day 28, these islands of cartilage grew and coalesced into a large homogenous mass of cartilage. There was no evidence of neovascularization in the 49- and 81- day implants, and there was decreasing evidence of an inflammatory response with time as characterized by a decrease in the number of polymorphonuclear leukocytes and giant cells. Very little evidence of the polymer fibers was seen after 28 days. This increase in the size of the cartilage appeared to be at the expense of the fibrous tissue previously seen and associated at least temporarily with a decrease in neovascularization and resolution of the mild inflammatory response originally noted. Also associated with this was the absorption of the biodegradable polymer fibers. In time, the polymer fibers were progressively replaced by
Dependencies are inferred from the claim text.