CD28 co-stimulation of T-cell-mediated cytotoxicity.

Abstract

Co-stimulation via the CD28 pathway permits small, resting human peripheral-blood T lymphocytes to mediate anti-CD3 monoclonal antibody (MAb) "re-directed" cytotoxicity. The effector cells are contained with the "memory" population of T lymphocytes, identified by expression of the CD45RO differentiation antigen. In this article, we review the requirements for initiating a cytolytic response and speculate on the physiological consequences of this process.