Rat Anti-Mouse CD5/Ly-1-UNLB

The purified (UNLB) antibody is supplied as 0.5 mg of purified immunoglobulin in 1.0 mL of borate buffered saline, pH 8.2. No preservatives or amine-containing buffer salts added. Store at 2-8 °C.

CD5/Lyt-1, Mr 67 kDa CD5/Lyt-1 antigen is a monomeric type I transmembrane glycoprotein expressed on thymocytes, T lymphocytes, and a subset of B lymphocytes, but not on natural killer (NK) cells.1-3 It has been identified as the major ligand of the B-cell antigen CD72.4, 5 The frequency of CD5+ B cells exhibits strain-dependent variation, and the phenotypic, anatomical, functional, developmental, and pathological characteristics of the CD5+ B cells suggest that they may represent a distinct lineage, known as B-1 cells (reviewed in 6). Binding of CD5 on the T cell surface can augment alloantigen- or mitogen-induced lymphocyte proliferation and induces increased cytosolic free calcium, IL-2 secretion, and IL-2R expression.7-12 It has been proposed that CD5 negatively regulates signal transduction mediated by the T-cell and B-cell receptors.13, 14