Abstract: The present invention provides methods and compositions for expanding Treg cells ex vivo or in vivo using one or more conjugates comprising a costimulatory moiety that stimulates at least one of three signals involved in Treg cell development and/or using dendritic cells pulsed with antigens and modified to display TGF-?, or hematopoetic stem cells or bone marrow cells modified to display TGF-?. The methods and compositions are useful, for example, in the treatment and prevention of autoimmune disease, including Type 1 diabetes and in preventing foreign graft rejection, as well as to establish mixed chimerism, induce tolerance to autoantigens, alloantigens or xenoantigens, beta cell regeneration, prevention of foreign graft rejection, and treatment of a genetically inherited hematopoietic disorder.

Abstract: The invention provides conjugates comprising an immune co-stimulatory polypeptide and an antigen or infectious agent. The conjugates are useful for generating or enhancing an immune response against the antigen or infectious agent. The invention also provides immune cells modified with a conjugate that are useful for generating or enhancing an immune response to an antigen or infectious agent. The invention also provides immunostimulatory moieties comprising an immune co-stimulatory polypeptide that are useful for stimulating an immune response. The invention also provides immunotherapy methods and methods of treating or preventing infections.

Abstract: The invention provides conjugates comprising an immune co-stimulatory polypeptide and an antigen or infectious agent. The conjugates are useful for generating or enhancing an immune response against the antigen or infectious agent. The invention also provides immune cells modified with a conjugate that are useful for generating or enhancing an immune response to an antigen or infectious agent. The invention also provides immunostimulatory moieties comprising an immune co-stimulatory polypeptide that are useful for stimulating an immune response. The invention also provides immunotherapy methods and methods of treating or preventing infections.

Abstract: Methods and compositions are provided for the persistent modification of cell membranes with exogenous proteins so as to alter the function of the cell to achieve effects similar to those of gene therapy, without the introduction of exogenous DNA. DNA sequences, the proteins and polypeptides embodying these sequences are disclosed for modulating the immune system. The modulations include down-regulation, up-regulation and apoptosis.

Abstract: The invention provides conjugates comprising an immune co-stimulatory polypeptide and an antigen or infectious agent. The conjugates are useful for generating or enhancing an immune response against the antigen or infectious agent. The invention also provides immune cells modified with a conjuagte that are useful for generating or enhancing an immune response to an antigen or infectious agent. The invention also provides immunostimulatory moieties comprising an immune co-stimulatory polypeptide that are useful for stimulating an immune response. The invention also provides immunotherapy methods and methods of treating or preventing infections.

Abstract: The present invention provides methods and compositions for expanding Treg cells ex vivo or in vivo using one or more conjugates comprising a costimulatory moiety that stimulates at least one of three signals involved in Treg cell development and/or using dendritic cells pulsed with antigens and modified to display TGF-?, or hematopoetic stem cells or bone marrow cells modified to display TGF-?. The methods and compositions are useful, for example, in the treatment and prevention of autoimmune disease, including Type 1 diabetes and in preventing foreign graft rejection, as well as to establish mixed chimerism, induce tolerance to autoantigens, alloantigens or xenoantigens, beta cell regeneration, prevention of foreign graft rejection, and treatment of a genetically inherited hematopoietic disorder.

Abstract: The present invention provides methods and compositions for the in vivo engineering of cell surfaces, such as tumor cell surfaces, with one or more immune co-stimulatory polypeptides. The methods, compositions and engineered cells are useful, for example, to stimulate an immune response against the cells. When the engineered cell surfaces are tumor cell surfaces, the methods, compositions and engineered cells are useful for improving a patient's immune response against the cancer and for reducing tumor size and inhibiting tumor growth.

Abstract: Methods and compositions are provided for the persistent modification of cell membranes with exogenous proteins so as to alter the function of the cell to achieve effects similar to those of gene therapy, without the introduction of exogenous DNA. DNA sequences, the proteins and polypeptides embodying these sequences are disclosed for modulating the immune system. The modulations include down-regulation, up-regulation and apoptosis.

Abstract: This invention provides chimeric proteins comprising an apoptosis-inducing molecule fused to a member of a binding pair that is capable of binding to a selected cell that expresses a death receptor. When the selected cell is exposed in vivo or ex vivo to the chimeric protein, the selected cell undergoes apoptosis. The preferred embodiment is FasL protein fused to streptavidin. The methods of using the chimeric proteins are especially beneficial in causing activated lymphocytes to undergo apoptosis, thus modulating the immune response. Patients with conditions such as asthma or allergy, or patients undergoing transplantation with allogeneic or xenogeneic tissue are examples of patients who benefit from the methods of this invention.

Abstract: Methods and compositions are provided for the persistent modification of cell membranes with exogenous proteins so as to alter the function of the cell to achieve effects similar to those of gene therapy, without the introduction of exogenous DNA. DNA sequences, the proteins and polypeptides embodying these sequences are disclosed for modulating the immune system. The modulations include down-regulation, up-regulation and apoptosis.

Abstract: This invention provides methods and compositions for caspase-induced apoptosis. Chimeric proteins are provided that target cells in which apoptosis is to be induced. The chimeric proteins of this invention activate endogenous caspase or provide caspase units that cause cell death. Methods are provided for the use of the chimeric proteins of this invention for in vivo and ex vivo therapies to treat pathological conditions.