Compositions and methods for preventing, reducing or inhibiting immunologic disorders are provided. Suitable compositions include one or more LIGHT-HVEM antagonists. LIGHT-HVEM antagonists include compounds that inhibit, reduce, or block the biological activity or expression of LIGHT and/or HVEM. LIGHT-HVEM antagonists can reduce or inhibit the binding of LIGHT to HVEM, but do not significantly modulate the binding of LTβ to LTβR. Suitable compositions include antibodies and antibody fragments, decoy polypeptides, small molecule inhibitors and inhibitory nucleic acids. Methods for using LIGHT-HVEM antagonists to reduce or inhibit T cell activation and survival are also provided. Therapeutic uses for LIGHT-HVEM antagonists to prevent or treat immunologic diseases and disorders including graft rejection, graft-versus-host disease, inflammatory immune responses, and autoimmune disorders are provided.
