Plasmodium berghei XAT: contribution of gammadelta T cells to host defense against infection with blood-stage nonlethal malaria parasite.
We examined a potential role of gammadelta T cells in protective immunity to blood-stage Plasmodium berghei XAT infection. Plasmodium berghei XAT is an attenuated variant of the lethal strain P. berghei NK65 and its infection is self-resolving in immune competent mice. To determine whether gammadelta T cells are essential for the resolution of P. berghei XAT malaria, mice were depleted of gammadelta T cells with anti-TCRgammadelta antibody treatment. Although mice that had received control antibody resolved infections, mice received anti-TCRgammadelta antibody could not control their infections and eventually died. Spleen cells from infected mice produced IFN-gamma and nitric oxide (NO) within the first week of infection, however, levels of IFN-gamma and NO in gammadelta T cell-depleted mice were significantly lower than in control mice. To examine whether gammadelta T cells are involved in the antibody production, malarial-specific antibodies of the various isotypes were measured in the sera of gammadelta T cell-depleted mice and control mice. Serum levels of IgG2a, which was known to be a protective antibody in P. berghei XAT malaria, were significantly lower in gammadelta T cell-depleted mice than in control mice, whereas levels of IgG1 were comparable to those in control mice. Our results indicated that the presence of the gammadelta T cell subset was essential for resolution of blood-stage P. berghei XAT malaria and played a modulatory role in the development of Th1 response and host defense against this malarial parasites.
Kobayashi
Fumie
F
Department of Infectious Diseases, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan. fumfum@kyorin-u.ac.jp
Niikura
Mamoru
M
Waki
Seiji
S
Matsui
Toshihiro
T
Fujino
Takashi
T
Tsuruhara
Takashi
T
Kamiya
Shigeru
S
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000913:Antibodies, Protozoan / Q000096:biosynthesis / Q000276:immunology; D000953:Antigens, Protozoan / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D004912:Erythrocytes / Q000276:immunology / Q000469:parasitology; D005260:Female; D005434:Flow Cytometry; D006825:Hybridomas; D007371:Interferon-gamma / Q000096:biosynthesis; D016753:Interleukin-10 / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008288:Malaria / Q000276:immunology*; D051379:Mice; D008808:Mice, Inbred CBA; D009569:Nitric Oxide / Q000096:biosynthesis; D010962:Plasmodium berghei / Q000276:immunology*; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000276:immunology*; D013154:Spleen / Q000166:cytology / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016692:Receptors, Antigen, T-Cell, gamma-delta; D016753:Interleukin-10; D015847:Interleukin-4; D009569:Nitric Oxide; D007371:Interferon-gamma