title: Toxoplasma gondii: kinetics of lymphocyte subsets in blood and spleen of perorally infected mice.
abstract: The blood and spleen lymphocyte subsets and parasite burdens in blood, lungs, and brain were determined serially in C57B1/6 mice infected with an avirulent strain of Toxoplasma gondii. Five mice were sacrificed at various time points after infection; Thy1-2+, Ly5+, CD4+, CD8+, and Ly6c+ lymphocyte subsets and macrophages were determined in blood and spleen by cytofluorometry and parasite burdens were quantified in blood, lungs, and brain by means of a tissue culture method. In infected mice, a large increase in the percentage of CD8+ lymphocytes in blood was observed from Day 14, peaking at Day 21; the percentage of CD4+ lymphocytes was not significantly modified compared with uninfected controls. Analysis of Ly6 antigen expression on T lymphocytes showed that CD8+Ly6c+ cells were largely predominant at the different stages of infection. Similar results were obtained for spleen cells. The marked increase in CD8+Ly6c+ cells in the early phase of infection was associated with the clearance of parasites from the lungs. Furthermore, the proportion of CD8+Ly-6c+ remained high until Day 162, when the infection was at the chronic stage. These results suggest that CD8+Ly6c+ lymphocytes may be involved in the control of toxoplasmosis in the acute phase and in the containment of the infection in the chronic stage.
authors.affiliation: INSERM U13, Paris, France.
authors.forename: B
authors.initials: B
authors.lastname: Carrof
authors.forename: M
authors.initials: M
authors.lastname: Levacher-Clergeot
authors.forename: F
authors.initials: F
authors.lastname: Chau
authors.forename: J J
authors.initials: JJ
authors.lastname: Pocidalo
authors.forename: F
authors.initials: F
authors.lastname: Derouin
mesh_terms: D000818:Animals; D001921:Brain / Q000469:parasitology; D016130:Immunophenotyping; D007700:Kinetics; D007958:Leukocyte Count; D008168:Lung / Q000469:parasitology; D016131:Lymphocyte Subsets / Q000276:immunology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D013154:Spleen / Q000166:cytology* / Q000276:immunology; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000097:blood / Q000276:immunology*