Description: The HIS24 monoclonal antibody reacts with an isoform of CD45 expressed by rat B cells. The antigen recognized by HIS24 is found on B cells from the early stage of B cell development in the bone marrow to mature peripheral B cells, but not on plasma cells. HIS24 recognizes a 205 kDa protein by immunoblotting. CD45, also known as Leukocyte Common Antigen (LCA), has tyrosine phosphatase enzymatic activity in its cytoplasmic portion and plays an important role in activation of lymphocytes.