CD2 (OKT11) augments CD3-mediated intracellular signaling events in human T lymphocytes.

CD2 (LFA-2) is expressed on thymocytes, natural killer cells, and virtually all peripheral T cells. CD2 binds to its primary ligand CD58 (LFA-3) on antigen presenting cells (APC) and stabilizes the T cell-APC interaction; this stable interaction then optimizes Ag-specific T-cell activation. We assessed whether CD2-cross-linking by mAb augments the process of T-cell stimulation through the TCR/CD3 complex.