Parenchymal cells packaged in immunoprotective tissue for implantation

Abstract

Cells for implantation into a patient are packaged within a barrier of immunoprotective tissue prior to implantation to obviate or minimize rejection of the cells. The preferred immunoprotective tissue for forming the barrier is cartilage. The tissue is formed into a layer that is thin enough to allow diffusion of nutrients and gases into the center of a cell mass packaged within the immunoprotective tissue. Typically the layer is less than 300 microns, preferably between 5 and 20 microns. Cells to be implanted, typically dissociated parenchymal cells including hepatocytes, Islets of Langerhans, or other cells having metabolic functions, are then placed on the tissue layer, and the layer is folded to seal the cells to be implanted within the tissue layer. In the preferred embodiment, the dissociated cells are first seeded onto a polymeric fiber matrix. The packaged cells are then implanted at a location providing an appropriate blood supply for diffusion of nutrients and gases through the tissue layer, for example, adjacent the mesentery. Islets of Langerhans are packaged within a tissue layer formed by a monolayer of chondrocytes seeded onto polymer fibers.

Dependencies are inferred from the claim text.