Abstract: The present invention generally relates to the treatment of uremic toxins in vivo using uremic toxin-treating enzymes, and/or cells capable of producing uremic toxin-treating enzymes or otherwise reacting with uremic toxins. Non-limiting examples of cases where the treatment of uremic toxins is desired include renal disease or dysfunction, gout, subjects receiving chemotherapy, or the like. In one aspect, the treatment includes an oral delivery composition able to reduce the blood concentration of one or more non-protein nitrogen compounds in vivo. The composition, in some cases, may comprise one, two, or more uremic toxin-treating enzymes, such as urease, uricase or creatininase. The oral delivery composition may be able to deliver the uremic toxin-treating enzymes, substantially undigested, to the intestines, where the enzymes can interact with uremic toxins transported to the intestines from the bloodstream.

Abstract: An immunoisolatory vehicle for the implantation into an individual of cells which produce a needed product or provide a needed metabolic function. The vehicle is comprised of a core region containing isolated cells and materials sufficient to maintain the cells, and a permselective, biocompatible, peripheral region free of the isolated cells, which immunoisolates the core yet provides for the delivery of the secreted product or metabolic function to the individual. The vehicle is particularly well-suited to delivery of insulin from immunoisolated islets of Langerhans, and can also be used advantageously for delivery of high molecular weight products, such as products larger than IgG. A method of making a biocompatible, immunoisolatory implantable vehicle, consisting in a first embodiment of a coextrusion process, and in a second embodiment of a stepwise process.

Abstract: An immunoisolatory vehicle for the implantation into an individual of cells which produce a needed product or provide a needed metabolic function. The vehicle is comprised of a core region containing isolated cells and materials sufficient to maintain the cells, and a permselective, biocompatible, peripheral region free of the isolated cells, which immunoisolates the core yet provides for the delivery of the secreted product or metabolic function to the individual. The vehicle is particularly well-suited to delivery of insulin from immunoisolated islets of Langerhans, and can also be used advantageously for delivery of high molecular weight products, such as products larger than IgG. A method of making a biocompatible, immunoisolatory implantable vehicle, consisting in a first embodiment of a coextrusion process, and in a second embodiment of a stepwise process.

Abstract: An immunoisolatory vehicle for the implantation into an individual of cells which produce a needed product or provide a needed metabolic function. The vehicle is comprised of a core region containing isolated cells and materials sufficient to maintain the cells, and a permselective, biocompatible, peripheral region free of the isolated cells, which immunoisolates the core yet provides for the delivery of the secreted product or metabolic function to the individual. The vehicle is particularly well-suited to delivery of insulin from immunoisolated islets of Langerhans, and can also be used advantageously for delivery of high molecular weight products, such as products larger than IgG. A method of making a biocompatible, immunoisolatory implantable vehicle, consisting in a first embodiment of a coextrusion process, and in a second embodiment of a stepwise process.

Abstract: An immunoisolatory vehicle for the implantation into an individual of cells which produce a needed product or provide a needed metabolic function. The vehicle is comprised of a core region containing isolated cells and materials sufficient to maintain the cells, and a permselective, biocompatible, peripheral region free of the isolated cells, which immunoisolates the core yet provides for the delivery of the secreted product or metabolic function to the individual.

Abstract: An immunoisolatory vehicle for the implantation into an individual of cells which produce a needed product or provide a needed metabolic function. The vehicle is comprised of a core region containing isolated cells and materials sufficient to maintain the cells, and a permselective, biocompatible, peripheral region free of the isolated cells, which immunoisolates the core yet provides for the delivery of the secreted product or metabolic function to the individual.

Abstract: A method of forming an implantable and retrievable immunoisolatory vehicles is disclosed, the method comprising the steps of first forming a core comprising a volume of at least 1 .mu.l and at least 10.sup.4 cells capable of providing a biologically active product or metabolic or immunologic function, said cells being dispersed in a biocompatible hydrogel or extracellular matrix, and then forming around the core a surrounding external biocompatible thermoplastic or hydrogel jacket free of said cells projecting externally thereof, said jacket having molecular weight cutoff permitting passage of molecules to and from the core through said jacket to provide said biologically active product or function.

Abstract: A method for treatment of a neurodegenerative condition in a patient comprising implanting in the patient at least one immunoisolatory vehicle comprising a corc comprising a volume of at least 1 .mu.l and at least 10.sup.4 living cells which secrete at least one biologically active product, said cells being dispersed in a biocompatible matrix comprising a hydrogel or extracellular matrix components, and an external jacket surrounding the core, the jacket comprising a biocompatible hydrogel or thermoplastic, the jacket being free of cells projecting externally thereof, said jacket having a molecular weight cutoff permitting the passage of the biologically active product from the core through the jacket.

Abstract: A method for treating diabetes in a patient comprising subcutaneously implanting in the patient at least one immunoisolatory vehicle comprising a core comprising a volume of at least 1 .mu.l and at least about 10.sup.4 living cells which secrete insulin, said cells being dispersed in a biocompatible matrix comprising a hydrogel or extracellular matrix components, and a surrounding external jacket of a biocompatible thermoplastic or hydrogel free of said cells projecting externally thereof, said jacket being permselective and immunoisolatory, said jacket having a molecular weight cutoff permitting passage of molecules between the patient and core through said jacket wherein the insulin is released from the immunoisolatory vehicle into the patient's body to treat diabetes.

Abstract: A method of forming an implantable and retrievable immunoisolatory vehicle is disclosed, the method comprising the steps of first forming a jacket of biocompatible thermoplastic or hydrogel, and then loading the jacket with a core comprising a volume of at least 1 .mu.l and at least 10.sup.4 cells capable of secreting a biocompatible matrix comprising a hydrogel or extracellular matrix, said jacket having a molecular weight cutoff permitting passage of molecules thereacross to provide said biologically active product or said function.

Abstract: A method of making an immunoisolatory vehicle comprised of a core comprising living cells dispersed in a biocompatible matrix is disclosed, the cells being capable of secreting a biologically active product or of providing a metabolic or immunologic function to an individual, and an external jacket surrounding said core which is a biocompatible, permselective thermoplastic or hydrogel, said jacket being free of said cells, comprising coextruding a suspension comprising said cells dispersed in a precursor matrix material comprising extracellular matrix components or a biocompatible hydrogel precursor, and a solution of a biocompatible jacket precursor from a nested dual-bore extrusion nozzle, wherein the suspension of (a) is coextruded from the inner bore and the solution of (b) is coextruded from the outer bore of the nozzle, to form said jacket as the solution of (b) and the suspension of (a) arc coextruded; and exposing the vehicle to a treatment that forms a core comprising a volume of at least 1 .mu.

Abstract: Immunoisolatory vehicles having a core and a surrounding jacket are disclosed, the core having a volume in excess of 1 .mu.l and at least about 10.sup.4 living cells capable of secreting a biologically active product or of providing a biological function to a patient, the cells dispersed in a biocompatible matrix formed of a hydrogel or an extracellular matrix component, and the external jacket being permselective, biocompatible and having a molecular weight cutoff permitting passage of molecules between the patient and the core through said jacket to provide said biological product or function.

Abstract: A method of providing a biologically active molecule or metabolic or immunologic function to a patient, comprising implanting into the body of the patient at least one immunoisolatory vehicle comprising a core comprising a volume in excess of 1 .mu.l and at least about 10.sup.4 living cells dispersed in a biocompatible matrix formed of a hydrogel or extracellular matrix components, said cells being capable of secreting a biologically active product or of providing a metabolic or immunologic function to the patient; and an external jacket surrounding said core, said jacket being formed from a thermoplastic or hydrogel, said jacket being free of said cells projecting externally therefrom, said jacket being biocompatible and having a molecular weight cutoff permitting passage of molecules between the patient and the core through said jacket to provide said biologically active product of function.

Abstract: A nozzle assembly for forming hollow fibers, particularly a "Z-fiber" having longitudinally oriented trabeculae with the fiber wall, is disclosed. The nozzle assembly contains a replaceable nozzle cap, a replaceable seal-guide, and a retractable central bore used to supply core material for the hollow fibers. The Z-fibers are particularly useful in enabling cells, solutes, or the like, to enter the fiber wall and move longitudinally into the center of the fiber wall.

Abstract: This invention provides methods for implanting encapsulated cells in a host comprising exposing cells to restrictive conditions for a sufficient period of time to establish a desired cell property in response to the restrictive conditions and implanting the encapsulated cells in a host, the cell property being substantially maintained following implantation. Also provided are cells produced by exposure to restrictive conditions.

Abstract: A nozzle assembly for forming hollow fibers, particularly a "Z-fiber" having longitudinally oriented trabeculae with the fiber wall, is provided. The nozzle assembly contains a replaceable nozzle cap, a replaceable seal-guide, and a retractable central bore used to supply core material for the hollow fibers. The Z-fibers are particularly useful in enabling cells, solutes, or the like, to enter the fiber wall and move longitudinally into the center of the fiber wall.

Abstract: Methods and systems for collection of blood components, such as plasma, from donors are provided. One method includes the steps of collecting a unit of whole blood from a donor; forcing the collected blood unit through a plasma separator; accumulating the plasma in a container; and returning concentrated cells to the donor. One system includes a disposable blood collection set and a reusable fixture into which the collection set can be mounted. The fixture is operated by a self-contained energy source, requiring no exterior electrical connection or other external source of energy.

Abstract: A material is formed into hollow fiber form, and the surface characteristics of the interior bore is selectively modified in a predetermined fashion by a reactive lumen fluid. Nucleophilic materials, such as regenerated cellulose, can be formed into hollow fibers and simultaneously modified to improve their biocompatibility in accordance with the invention.

Abstract: A method and apparatus for optimizing parameters of a hollow membrane filter results in a relatively small filter when a predetermined, substantially constant, driving pressure drop is applied between the inlet and the outlet of the filter. The method includes simultaneous solution of a set of equations to specify fiber length, number and internal diameter. A system including a computer can make optimized filters in response to the determined parameters.

Abstract: Methods and systems for collection of blood components, such as plasma, from donors are provided. One method includes the steps of collecting a unit of whole blood froma donor; forcing the collected blood unit through a plasma separator; accumulating the plasma in a container; and returning concentrated cells to the donor. One system includes a disposable blood collection set and a reusable fixture into which the collection set can be mounted. The fixture is operated by a self-contained energy source, requiring no exterior electrical connection or other external source of energy.