Spleen and lymph node cell populations, in vitro cell proliferation and interferon-gamma production during the primary immune response to Toxoplasma gondii.
An animal model for the study of transient lymphadenopathy-splenomegaly during toxoplasmosis is presented. Injection of CBA/J mice with the low virulent, cyst-forming strain of Toxoplasma gondii (Pe strain) induces a three to four fold increase in weight and cellularity of spleen and lymph nodes with peak changes at 30-50 days after infection. The spleen displays marked haemopoiesis, a 30 fold increase in mononuclear phagocytes, and a two fold increase in Lyt2+ lymphocytes. Lymph nodes show a five fold increase in mononuclear phagocytes and a four and a half fold increase in Lyt2+ T cells. The increase in mononuclear phagocytes significantly alters T cell/macrophage ratios and this is associated with decreases in in vitro cell proliferation to mitogen and toxoplasma antigen. The relationship between alterations in cell balance of mononuclear phagocytes and T cell subsets and the expression of transient immune dysfunction can now be examined by modulating changes in these cell types.
D000818:Animals; D000953:Antigens, Protozoan / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis*; D008198:Lymph Nodes / Q000276:immunology*; D008213:Lymphocyte Activation; D008264:Macrophages / Q000276:immunology; D051379:Mice; D008808:Mice, Inbred CBA; D013154:Spleen / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014122:Toxoplasma / Q000302:isolation & purification; D014124:Toxoplasmosis, Animal / Q000276:immunology*
D000953:Antigens, Protozoan; D007371:Interferon-gamma