title: Analysis of Ia-antigen(s) positive macrophages in experimental murine toxoplasmosis.
abstract: The present study has demonstrated marked increase in the relative percentage of Ia-positive macrophages among the peritoneal macrophage population(s) of BALB/c mice infected intraperitoneally with Toxoplasma gondii or when chronically infected mice were rechallenged with Toxoplasma. The observed increase in Ia-positive peritoneal macrophage numbers coincided with the appearance of interferon-gamma (IFN-gamma) in the sera of infected mice. The appearance of elevated serum IFN-gamma titer was a temporary event but the increased percentage of Ia-positive macrophages persisted. The data presented have documented that antigen-specific proliferation response of vigorously purified Toxoplasma-sensitized T-cells is dependent upon Ia-bearing macrophages. This model is useful for future studies into various aspects of the interaction(s) between parasite antigens and Ia-antigen(s) at the macrophage surface for successful recognition of antigen-specific T-cells.
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D001202:Ascitic Fluid / Q000276:immunology; D002450:Cell Communication; D000949:Histocompatibility Antigens Class II; D007371:Interferon-gamma / Q000097:blood; D008213:Lymphocyte Activation; D008262:Macrophage Activation; D008264:Macrophages / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013601:T-Lymphocytes / Q000276:immunology; D014124:Toxoplasmosis, Animal / Q000276:immunology*
chemical_list: D000949:Histocompatibility Antigens Class II; D007371:Interferon-gamma