Abstract: The present invention is directed to a method of treating a patient with diabetes by implanting an improved macrocapsule containing living islet cells in the patient. The improved macrocapsules encapsulate microcapsules containing islet cells, to make the system more biocompatible by decreasing the surface area and surface roughness of microencapsulated biological materials; increasing stability of microencapsulated islet cells; enhancing cytoprotectivity by increasing diffusion distance of encapsulated islet cells from cytotoxins secreted in vivo; providing retrievability of microencapsulated material; and providing a system of sustained release of the cellular products.

Abstract: In accordance with the present invention, there are provided methods to render cells non-adhesive and/or non-immunogenic with respect to macromolecules typically encountered in culture media or in physiological media.

Abstract: The present invention is directed to a macrocapsule for encapsulating microcapsules containing biologically active material, such as living cells or free living cells, to make the system more biocompatible by decreasing the surface area and surface roughness of microencapsulated biological materials; increasing mechanical stability of microencapsulated biological materials; enhancing cytoprotectivity by increasing diffusion distance of encapsulated biological material from cytotoxins secreted in vivo; providing retrievability of microencapsulated material; and providing a system of sustained release of the cellular products. The method for producing such a macrocapsule containing the microcapsules is also disclosed.

Abstract: In accordance with the present invention, it has been discovered that a major reason for the failure to achieve successful in vivo transplantation in large mammalian species has been flaws associated with the design of microcapsules taught in the prior art, flaws in the method of making such microcapsules, and a lack of tests to determine if a given microcapsule will be successful. In accordance with the present invention, a number of functional properties which must be met by a microcapsule in order to achieve successful in vivo transplantation in large animal models have been identified. These properties include (i) a mechanically stable capsule core, (ii) a mechanically strong capsule membrane (i.e., the membrane must be of sufficient strength to prevent capsule disruption), (iii) the absence of excess exposed positively-charged PLL (which leads to fibrosis), and (iv) an adequate level of diffusion of the entrapped biologically active material out of the capsule.

Abstract: The present invention is directed to a macrocapsule for encapsulating microcapsules containing biologically active material, such as living cells or free living cells, to make the system more biocompatible by decreasing the surface area and surface roughness of microencapsulated biological materials; increasing mechanical stability of microencapsulated biological materials; enhancing cytoprotectivity by increasing diffusion distance of encapsulated biological material from cytotoxins secreted in vivo; providing retrievability of microencapsulated material; and providing a system of sustained release of the cellular products. The method for producing such a macrocapsule containing the microcapsules is also disclosed.

Abstract: In accordance with the present invention, there are provided methods to render cells non-adhesive and/or non-immunogenic with respect to macromolecules typically encountered in culture media or in physiological media. The invention method comprises contacting cells with an effective amount of a composition comprising a polycationic species having water-soluble polymer chains grafted thereon.

Abstract: Crosslinked biocompatible compositions comprising an ionically crosslinked component and a covalently crosslinked component for encapsulating biologics are disclosed. In accordance with the present invention, also disclosed are crosslinkable biocompatible mixtures comprising an ionically crosslinkable component and a covalently crosslinkable component. Methods for encapsulating biologics with the crosslinked and cross-linkable biocompatible compositions are provided. Also, retrievable macrocapsules for encapsulating microcapsules or biologics are disclosed.

Abstract: The present invention is directed to a macrocapsule for encapsulating microcapsules containing biologically active material, such as living cells or free living cells, to make the system more biocompatible by decreasing the surface area and surface roughness of microencapsulated biological materials; increasing mechanical stability of microencapsulated biological materials; enhancing cytoprotectivity by increasing diffusion distance of encapsulated biological material from cytotoxins secreted in vivo; providing retrievability of microencapsulated material; and providing a system of sustained release of the cellular products. The method for producing such a macrocapsule containing the microcapsules is also disclosed.

Abstract: Crosslinked biocompatible compositions comprising an ionically crosslinked component and a covalently crosslinked component for encapsulating biologics are disclosed. In accordance with the present invention, also disclosed are crosslinkable biocompatible mixtures comprising an ionically crosslinkable component and a covalently crosslinkable component. Methods for encapsulating biologics with the crosslinked and crosslinkable biocompatible compositions are provided. Also, retrievable macrocapsules for encapsulating microcapsules or biologics are disclosed.