title: A rapid flow cytometric method to explore cellular immunity against Toxoplasma gondii in humans.
abstract: To assess cell-mediated immunity to Toxoplasma gondii, we evaluated the expression of the activation antigens CD69, CD71, and CD25 on T lymphocytes by flow cytometry after specific in vitro stimulation of whole blood from 127 T. gondii-positive and 63 T. gondii-negative patients. T lymphocytes from many seropositive individuals did not express CD69 at 24 h after T. gondii antigen stimulation, but CD71 and CD25 were easily detectable on T cells from seropositive individuals 7 days after specific activation. CD25 was mainly expressed by stimulated CD4(+) T cells, and its detection on total T cells was both a sensitive (98%) and a specific (97%) indicator of prior T. gondii infection. These results make flow cytometric detection of CD25 an excellent candidate for screening cell-mediated immunity to T. gondii in vitro and an interesting tool for the diagnosis of congenital infection.
authors.affiliation: Université Claude Bernard Lyon I, JE 1947, Lyon, France.
authors.forename: S
authors.initials: S
authors.lastname: Kahi
authors.forename: G J
authors.initials: GJ
authors.lastname: Cozon
authors.forename: T
authors.initials: T
authors.lastname: Greenland
authors.forename: M
authors.initials: M
authors.lastname: Wallon
authors.forename: F
authors.initials: F
authors.lastname: Gay-Andrieu
authors.forename: F
authors.initials: F
authors.lastname: Peyron
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000032:analysis; D000944:Antigens, Differentiation, B-Lymphocyte / Q000032:analysis; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis; D000953:Antigens, Protozoan / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005434:Flow Cytometry / Q000379:methods*; D006801:Humans; D037181:Lectins, C-Type; D008213:Lymphocyte Activation; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000032:analysis*; D011990:Receptors, Transferrin; D012680:Sensitivity and Specificity; D013601:T-Lymphocytes / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology*; D014125:Toxoplasmosis, Congenital / Q000175:diagnosis; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000944:Antigens, Differentiation, B-Lymphocyte; D000945:Antigens, Differentiation, T-Lymphocyte; D000953:Antigens, Protozoan; D037181:Lectins, C-Type; D015375:Receptors, Interleukin-2; D011990:Receptors, Transferrin; D000099192:CD69 Antigens; C068126:CD71 antigen