title: Rapid response to Con A by CD4+CD45R- rat memory lymphocytes as compared to CD4+CD45R+ lymphocytes.
abstract: Functionally distinct subpopulations within the CD4+ subset of T lymphocytes have been described in man, rat, and mouse. In the rat different functions have been assigned to CD45R+ and CD45R- T helper cells. The CD45R+ in contrast to the CD45R- T helper cells have been reported to produce IL-2 and to proliferate well in response both to Con A and in MLR. In the present investigation the kinetics of the response to Con A by the CD45R+ and CD45R- rat T helper subsets have been analyzed. We confirm a strong proliferative response to Con A by CD4+CD45R+ rat T lymphocytes and also that they are the best IL-2 producers. We further demonstrate that CD4+CD45R- cells also produce IL-2, although in order to appreciate this production quantitatively by assays of the culture supernatants it was necessary to block IL-2 absorption by IL-2 receptor (IL-2R) antibodies. This blockage was of importance also in comparisons of the two subsets, since they showed different kinetics of IL-2R appearance. It is demonstrated that the CD4+CD45R- cells respond more rapidly to Con A than the CD4+CD45R+ cells as reflected by phenotypic conversion, IL-2 production, and proliferation. The fast response of the CD4+CD45R- T subset shown in the present study of rat cells and analogous studies of human cells suggests that the memory compartment of T cells besides other characteristics also has the capacity for a more rapid response than naive lymphocytes.
authors.affiliation: Department of Tumor Immunology, Wallenberg Laboratory, University of Lund, Sweden.
authors.forename: G
authors.initials: G
authors.lastname: Hedlund
authors.forename: M
authors.initials: M
authors.lastname: Dohlsten
authors.forename: P O
authors.initials: PO
authors.lastname: Ericsson
authors.forename: H O
authors.initials: HO
authors.lastname: Sjögren
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000943:Antigens, Differentiation / Q000032:analysis*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D003208:Concanavalin A / Q000494:pharmacology*; D007156:Immunologic Memory; D007376:Interleukin-2 / Q000096:biosynthesis; D017493:Leukocyte Common Antigens; D008213:Lymphocyte Activation / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D011990:Receptors, Transferrin / Q000032:analysis; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000943:Antigens, Differentiation; D000945:Antigens, Differentiation, T-Lymphocyte; D007376:Interleukin-2; D011990:Receptors, Transferrin; D003208:Concanavalin A; D017493:Leukocyte Common Antigens