Characterization of a monoclonal rat anti-mouse interleukin 2 (IL-2) receptor antibody and its use in the biochemical characterization of the murine IL-2 receptor.
Anti-murine interleukin 2 (IL-2) receptor monoclonal antibodies (mAb) were made from rats immunized with murine cytotoxic lymphocytes. One mAb, designated M7/20, strongly inhibited the proliferation of both IL-2 dependent CTLL-2 cells and concanavalin A (Con A)-induced T-cell blasts. Inhibition was linearly dependent on the concentrations of both M7/20 and IL-2. Utilizing FACS analysis, M7/20 was shown to bind selectively to mitogen-activated T lymphocytes and, to a lesser degree, to activated B lymphocytes. 125I-Labeled M7/20 binding assays indicated that 48-hr Con A-induced T-cell blasts possessed 89,000 binding sites/cell with a Kd of 1.2 X 10(-9) M. Competitive binding analyses indicated that M7/20 and IL-2 occupy the same or overlapping cell surface sites. Preliminary biochemical characterization of M7/20 immunoprecipitates of detergent extracts from both surface-iodinated and internally D-[3H]glucosamine-labeled T lymphoblasts indicated that the murine IL-2 receptor is an N-glycosylated 58,000-Da glycoprotein. Together these results suggest that mAb M7/20 binds at or near the IL-2-binding epitope on the murine IL-2 receptor and, thus, upon manipulation may act as an IL-2 agonist.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000917:Antibody Formation; D003208:Concanavalin A / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D007376:Interleukin-2 / Q000096:biosynthesis; D007700:Kinetics; D008213:Lymphocyte Activation; D051379:Mice; D051381:Rats; D011971:Receptors, Immunologic / Q000276:immunology*; D015375:Receptors, Interleukin-2; D012967:Sodium Dodecyl Sulfate; D013045:Species Specificity
D000911:Antibodies, Monoclonal; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D003208:Concanavalin A; D012967:Sodium Dodecyl Sulfate