Abstract: This disclosure relates to compositions and methods for encapsulating biomaterials such as cells to prevent immune responses. In certain embodiments, the disclosure relates to capsules comprising a cell or cells gelled in alginate coated with a layer that prevents migration of immune molecules to the cell surface and an outer capsule layer comprising non-immunogenic material optionally containing immunosuppressive agents. In certain embodiments, the cells are capable of generating insulin that emanates from the capsule.

Abstract: It has been discovered that human parathyroid tumor cells express high densities of folate receptors which could provide a target that may be used for localization. In certain embodiments, the disclosure relates to methods of detecting and imaging parathyroid tumors or canccrous cells in tissues using a folatc conjugate to enhance imaging techniques such as magnetic resonance imaging, positron emission tomography, computed tomography (CT), and single-photon emission computed tomography (SPECT). An image of radioactivities or nuclear magnetic resonance frequencies as a function of location for parcels (voxels), may be constructed and plotted. The image shows the tissues in which the tracer has become concentrated.

Abstract: This disclosure relates to compositions and methods for encapsulating biomaterials such as cells to prevent immune responses. In certain embodiments the disclosure relates to capsules comprising a cell or cells gelled in alginate coated with a layer that prevents migration of immune molecules to the cell surface and an outer capsule layer comprising non-immunogenic material optionally containing immunosuppressive agents. In certain embodiments, the cells are capable of generating insulin that emanates from the capsule.

Abstract: This invention provides a method of inhibiting viable cells transplanted into a subject from being destroyed by the subject's immune system which comprises: a) containing the viable cells, or tissue comprising the viable cells, prior to transplantation within a device comprising a semipermeable membrane; and b) treating the subject with a substance which inhibits an immune-system costimulation event in an amount effective to inhibit the subject's immune system from responding to said contained cells or tissue. In one embodiment, the substance which inhibits an immune-system costimulation event is CTLA4.

Abstract: This invention provides a method of inhibiting viable cells transplanted into a subject from being destroyed by the subject's immune system which comprises: a) containing the viable cells, or tissue comprising the viable cells, prior to transplantation within a device comprising a semipermeable membrane; and b) treating the subject with a substance which inhibits an immune-system costimulation event in an amount effective to inhibit the subject's immune system from responding to said contained cells or tissue. In one embodiment, the substance which inhibits an immune-system costimulation event is CTLA4.

Abstract: A core material such as animal tissue or cells is contained within a semipermeable vessel which may be a microcapsule, hollow fiber or plastic membrane having a semipermeable wall by a method that prevents the core material from incorporation into the wall of the vessel. This is accomplished by suspending the core material in a solution of polysaccharide gum such as an alkali metal alginate in an amount between about 0.2% and about 0.5%, removing and washing the core material to remove all but a thin layer of polysaccharide gum, and gelling the polysaccharide gum with multivalent cations or other means to form a pretreated core material.

Abstract: The subject invention provides a method of encapsulating viable tissue or cells within a double walled bead, the double-walled bean produced as a result of the method, as well as a method of pretreating the tissue or cells with an immunosuppressant such as UV-B irradiation prior to their encapsulation.