Immune Intervention with Monoclonal Antibodies Targeting CD152 (CTLA-4) for Autoimmune and Malignant Diseases

CD152 or cytotoxic T lymphocyte antigen-4 (CTLA-4) isan essential receptor involved in the negative regulation of Tcell activation. Because of its profound inhibitory role, CD152has been considered a sound susceptible candidate in autoimmunityand a persuasive target for cancer immunotherapy forover a decade. However, the precise roles played by this moleculecontinue to emerge. In particular, recent evidence suggeststhat CD152 is also important in the homeostasis and functionof a population of suppressive cells, termed regulatory T cells(Treg). In this review, we discuss the recent progress and mainfeatures of monoclonal antibodies (mAbs) targeting CD152and examine how each mAb prepared to a distinct epitope mayimpact differently upon CD152 modulation depending on itsdemonstrated regulatory role acting as an agonist, antagonist,or inverse agonist.