Abstract: Described herein are compositions and methods for treating or preventing an injury associated with transplant. Specifically, the disclosure provides a composition for treating or preventing an injury associated with transplantation, comprising (a) a targeted inhibitor molecule wherein the targeted inhibitor molecule comprises a targeting portion and an inhibitor portion, wherein the molecule inhibits complement pathways, and (b) a sub-therapeutic dose of an immunosuppressant agent. Further provided are methods of treating or preventing an injury associated with transplantation with activated complement by using the compositions.

Abstract: The present invention provides methods for suppressing, reducing or even reversing an immune response. More particularly it concerns anti-CD28 monoclonal antibody compositions and methods for preventing graft-versus-host disease (GVHD), transplant tissue rejection, and treating autoimmune diseases and the like. In particular embodiments, a method of inhibiting an immune response comprises administering an effective amount of a purified anti-CD28 antibody preparation to a subject, wherein the preparation modulates the CD28 receptor thereby inhibiting an immune response.