title: Cellular control of abscess formation: role of T cells in the regulation of abscesses formed in response to Bacteroides fragilis.
abstract: Although abscesses are a major sequela of infection, little is known about which cellular events initiate and which prevent this pathologic response. These studies are the first to indicate a role for T cells in the important pathogenic process of abscess development and also in immunity to abscesses induced by Bacteroides fragilis. We have shown that T cells initiate the formation of abscesses in mice after i.p. challenge with B. fragilis. These T cells bear both Ly-1 and Ly-2 surface markers. Nude mice (which have been shown by others to have T cell or T cell precursors) are also able to form abscesses. Cyclophosphamide-treated mice (with depressed T cell function) were not capable of developing abscesses. Reconstitution with normal or nude mouse spleen cells restored this ability. However, reconstitution with anti-Thy-1.2-treated, anti-Ly-1, or anti-Ly-2-treated spleen cells (or a mixture of the two cell populations) failed to allow abscess formation after bacterial challenge. Immunity to abscesses caused by B. fragilis requires two T cells. The first Ly-1-2+ T cell has an IJ surface marker and has been shown to release a small m.w. soluble factor (ITF) that is antigen specific. Immunity to abscesses, however, depends on the interaction of ITF with a second Ly-1-2+ T cell, demonstrated in reconstitution experiments with nude mice. The data presented document a critical role for T cells in abscess induction and suggest the existence of a suppressor-like T cell circuit in immunity to abscesses.
mesh_terms: D000038:Abscess / Q000209:etiology / Q000276:immunology*; D000818:Animals; D000950:Antigens, Ly; D001442:Bacteroides Infections / Q000209:etiology / Q000276:immunology*; D001441:Bacteroides fragilis / Q000276:immunology; D007111:Immunity, Cellular; D007116:Immunization, Passive; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008819:Mice, Nude; D010641:Phenotype; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology* / Q000637:transplantation
chemical_list: D000950:Antigens, Ly