title: Intercellular interactions and cytokine responsiveness of peritoneal alpha/beta and gamma/delta T cells from Listeria-infected mice: synergistic effects of interleukin 1 and 7 on gamma/delta T cells.
abstract: Peritoneal gamma/delta T cells from Listeria-immune mice show an enhanced potential to expand when restimulated with antigens or mitogens in vitro (see companion paper [Skeen, M. J., and H. K. Ziegler. 1993. J. Exp. Med. 178:971]). When cocultured with peritoneal alpha/beta T cells, the gamma/delta T cell population expanded preferentially even when the in vitro stimulus was specific for the alpha/beta T cell population. Purified gamma/delta T cells did not respond to alpha/beta T cell-specific stimuli. If isolated T cell subsets were recombined in cell mixing experiments, the resulting proliferative response was greater than additive. Irradiated alpha/beta T cells could enhance the proliferation of responding gamma/delta T cells, but the effect was unidirectional; i.e., irradiated gamma/delta T cells did not stimulate responding gamma/delta T cells. This effect appeared to be cytokine mediated and did not require cell-cell contact. Both recombinant interleukin 2 (rIL-2) and rIL-7 could support the expansion of the gamma/delta T cells, while rIL-7 was only minimally stimulatory for the alpha/beta T cells. The magnitude of the response by gamma/delta T cells to rIL-7 exceeded the response to other in vitro stimuli, including immobilized anti-T cell receptor monoclonal antibody, and was 50-100-fold greater than the alpha/beta T cell response to IL-7. This unique sensitivity of gamma/delta T cells to IL-7 was strongly enhanced by the presence of accessory cells. These cells could be replaced by rIL-1, establishing a synergy for IL-1 and IL-7 as factors that could uniquely stimulate this gamma/delta T cell population. Isolated peritoneal gamma/delta T cells from Listeria-immune mice react to heat-killed Listeria preparations in the presence of macrophages accessory cells in a non-H-2-restricted manner. Considered collectively, these results suggest a potential mechanism by which gamma/delta T cells can predominate in epithelial tissues and at sites of infection.
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, Georgia 30322.
authors.forename: M J
authors.initials: MJ
authors.lastname: Skeen
authors.forename: H K
authors.initials: HK
authors.lastname: Ziegler
mesh_terms: D000818:Animals; D016207:Cytokines / Q000502:physiology*; D004357:Drug Synergism; D005260:Female; D007375:Interleukin-1 / Q000008:administration & dosage; D015851:Interleukin-7 / Q000008:administration & dosage; D008088:Listeriosis / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000502:physiology; D051379:Mice; D008809:Mice, Inbred C3H; D010529:Peritoneal Cavity / Q000166:cytology; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000378:metabolism*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000276:immunology*
chemical_list: D016207:Cytokines; D007375:Interleukin-1; D015851:Interleukin-7; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta