Antigen presentation by Toxoplasma gondii-infected cells to CD4+ proliferative T cells and CD8+ cytotoxic cells.
Cytotoxic cells specific for Toxoplasma gondii-infected cells were detected in the peripheral blood leukocytes from a patient with acute toxoplasmosis. The cytotoxicity was mediated by CD5+, CD4-, CD8+ cells. The cytotoxic T cells lysed Toxoplasma-infected target cells with HLA class I restriction. Two types of T cell clones were established from peripheral blood leukocytes of a patient with chronic toxoplasmosis; one was a CD5+, CD4-, CD8+ cytotoxic cell specific for Toxoplasma-infected cells, and the other was a CD5+, CD4+, CD8- proliferative cell that responded to Toxoplasma antigen. Toxoplasma-infected cell-specific cytotoxic cloned T cells recognize the infected target cells in the context of the HLA class I molecules, and the CD8 molecule was involved in the cytotoxicity. Toxoplasma antigen-specific proliferative cloned T cells were stimulated by Toxoplasma antigen-pulsed or Toxoplasma-infected cells in conjunction with HLA-DR molecule on the target cells. Thus, antigen presentation by Toxoplasma-infected cells for activation of both cytotoxic and proliferative T cells has been demonstrated.
Yano
A
A
Department of Parasitology, Shinshu University School of Medicine, Matsumoto, Japan.
Aosai
F
F
Ohta
M
M
Hasekura
H
H
Sugane
K
K
Hayashi
S
S
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology; D000953:Antigens, Protozoan / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D006684:HLA-DR Antigens / Q000276:immunology; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D006801:Humans; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology*
D000945:Antigens, Differentiation, T-Lymphocyte; D000953:Antigens, Protozoan; D006684:HLA-DR Antigens; D015395:Histocompatibility Antigens Class I