title: Virgin and memory T cells have different requirements for activation via the CD2 molecule.
abstract: T cells can be divided into unprimed virgin (T0) and primed memory (T') subpopulations by their expression of different isoforms of the leukocyte common antigen. We have separated the CD4+ T cells into T0 and T' subpopulations and examined their capacity to respond to activation signals via the CD2 receptor molecule. On stimulation with a mitogenic combination of anti-CD2 antibodies, the T' population was induced to express IL-2 receptor, increased levels of the 4F2 antigen and to proliferate, whereas the response of the T0 populations was reflected solely by a minimal increase in the 4F2 antigen. The addition of IL-2 or monocytes to T0 cells stimulated with anti-CD2 antibodies did not enhance their expression of the IL-2 receptor or proliferation. However, T0 cells stimulated with the triad of anti-CD2 antibodies, monocytes, and IL-2 responded with high levels of IL-2 receptor expression and proliferation. The T0 subpopulation could also be induced to respond when cultured with anti-CD2 antibodies and phorbol myristate acetate. The results suggest that in order to respond to stimulation via the CD2 molecule, virgin T helper cells require additional signals that can be jointly provided by monocytes and IL-2. In contrast, memory T helper cells can be activated via CD2 signal transduction alone.
authors.affiliation: Division of Development and Clinical Immunology, University of Alabama, Birmingham 35294.
authors.forename: J A
authors.initials: JA
authors.lastname: Byrne
authors.forename: J L
authors.initials: JL
authors.lastname: Butler
authors.forename: E L
authors.initials: EL
authors.lastname: Reinherz
authors.forename: M D
authors.initials: MD
authors.lastname: Cooper
mesh_terms: D000906:Antibodies; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D018801:CD2 Antigens; D027261:Fusion Regulatory Protein-1; D006801:Humans; D007156:Immunologic Memory; D066298:In Vitro Techniques; D007376:Interleukin-2 / Q000494:pharmacology; D008213:Lymphocyte Activation / Q000187:drug effects; D009000:Monocytes / Q000276:immunology; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2 / Q000187:drug effects / Q000378:metabolism; D015398:Signal Transduction / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000906:Antibodies; D000945:Antigens, Differentiation, T-Lymphocyte; D000954:Antigens, Surface; D018801:CD2 Antigens; D027261:Fusion Regulatory Protein-1; D007376:Interleukin-2; D011971:Receptors, Immunologic; D015375:Receptors, Interleukin-2; D013755:Tetradecanoylphorbol Acetate