title: Interleukin-2 production by mitogen-stimulated intestinal mucosal leukocytes from cattle.
abstract: Leukocytes isolated from intraepithelium, lamina propria, and aggregated lymphatic follicles of the small intestine of healthy adult cattle were tested for their ability to produce interleukin 2 (IL-2) by in vitro stimulation of cells with mitogens. Supernatants from interepithelial leukocytes, lamina propria leukocytes, and cultures stimulated with concanavalin A (conA), phytohemagglutinin, and pokeweed mitogen contained growth factors with the capacity to maintain proliferation of a bovine IL-2-dependent lymphoblastoid cell line. Interleukin-2 activity was demonstrated in supernatants of all 3 conA-stimulated leukocyte populations as early as 20 hours after initiation of culture, reached peak values at 30 to 50 hours, and decreased by 72 hours. Although quantitative variations of IL-2 production were observed between various cell types and among cattle, conA was the most potent in inducing IL-2 activity in all 3 leukocyte populations. Supplementation of culture medium with 2-mercaptoethanol or phorbol myristrate acetate neither induced IL-2 production nor enhanced mitogen-induced IL-2 production. Addition of indomethacin to conA-stimulated cultures enhanced IL-2 production. Although depletion of adherent cells did not affect IL-2 production, total elimination of Ia-positive accessory cells inhibited its production by all 3 cell populations. Lymphocytes responsible for IL-2 production in aggregated lymphatic follicle population were presumptive T cells because they were nylon wool-nonadherent, B26A positive (monoclonal antibody directed against pan T cells), pIg45A negative (antibody directed against pan B cells), and considered peanut agglutination-positive.
authors: Department of Veterinary Microbiology, University of Saskatchewan, Saskatoon, Canada.
authors: A M
authors: AM
authors: Nagi
authors: L A
authors: LA
authors: Babiuk
mesh_terms: D000818:Animals; D002417:Cattle / Q000276:immunology*; D003208:Concanavalin A / Q000494:pharmacology; D004847:Epithelial Cells; D007376:Interleukin-2 / Q000096:biosynthesis*; D007413:Intestinal Mucosa / Q000166:cytology*; D007421:Intestine, Small / Q000166:cytology; D007962:Leukocytes / Q000276:immunology* / Q000378:metabolism; D008213:Lymphocyte Activation; D010835:Phytohemagglutinins / Q000494:pharmacology; D011043:Pokeweed Mitogens / Q000494:pharmacology
chemical_list: D007376:Interleukin-2; D010835:Phytohemagglutinins; D011043:Pokeweed Mitogens; D003208:Concanavalin A