Abstract: The present invention provides a convenient polymeric film or microparticulate vehicle to deliver protein factors into appropriate body sites to induce appropriate therapeutic effects. It also improves the existing methodologies for immunoisolation of non-human pancreatic islets (via microencapsulation) to protects them from the immunologically-different host. This invention demonstrates how vascularization and angiogenesis can be induced by means of addition of proper angiogenic factors. The angiogenesis is sustained over a long period of time, depending on the release characteristics of the polymeric matrix. Three-dimensional polymeric structures (mesh or perforated tubing and film) are used as resident materials for microcapsules bearing islets. Blood capillaries are generated outside the capsules and penetrate through the implant openings to ingrow into the vicinity of capsules/islets.

Abstract: Microparticles and nanoparticles prepared from oppositely charged polymers are provided in which a drug is incorporated into the core and is conjugated to one polymer by a Schiff-base crosslink. The particles are suitable for use in injectable formulations in which the rate of release of the drug through the particle shell is slowed as compared to noncrosslinked drugs. Enzymatically degradable polymers can be incorporated in otherwise hydrolytically stable particles to provide drug release at particular sites within the body where the enzyme of interest is present.

Abstract: The present invention is drawn to a composition of matter comprising high viscosity sodium alginate, cellulose sulfate and a multi-component polycation. Additionally, the present invention provides methods for making capsules, measuring capsule permeability to immunologically-relevant proteins and treating disease in an animal using encapsulated cells.Over one thousand combinations of polyanions and polycations were examined as polymer candidates suitable for encapsulation of living cells and thirty-three pairs were effective. The combination of sodium alginate, cellulose sulfate, poly(methylene-co-guanidine) hydrochloride, calcium chloride, and sodium chloride produced the most desirable results. Pancreatic islets encapsulated in this multicomponent capsule demonstrated glucose-stimulated insulin secretion in vitro and reversed diabetes without stimulating immune reaction in mice.