Mouse Monoclonal. Intended for in vitro diagnostic (IVD) use. This antibody is specific to a 55 kDa protein known as interleukin 2-receptor α (IL-2R α). IL-2R α is over expressed on the surface of activated T cells, HTLV-1 or HTLV-2 positive T cell lines and moderately expressed on activated B cells, NK-cells and macrophages. References Letoureau S, et al. IL-2- and CD25-dependent immunoregulatory mechanisms in the homeostasis of T-cell subsets. Clin Immunol. 2009; 123:758-62.