Function of CD8+ T lymphocytes in a self-curing mouse model of visceral leishmaniasis.
CD8+ T lymphocytes play an important role in the control of visceral leishmaniasis in non self-cure mice (e.g. BALB/c). In the present study, the mode of action of CD8+ T cells and their in vivo contribution to immunity was addressed in self-curing C57BL/6 mice. During the course of the experimental infection, CD8+ T cells specific for Leishmania infantum (L. infantum) developed and apoptotic cell death subsequently followed. They exhibited perforin-dependent cytotoxicity and a T(C)1 profile characterized by secretion of IFN-gamma and CC chemokines. Despite evidence for activation of CD8+ T lymphocytes, both intravenous and intradermal infection of beta2-microglobulin deficient C57BL/6 mice with L. infantum showed that these knockout animals had similar parasite loads to their wild-type counterpart. Lymphocytes from the beta2-microglobulin deficient mice produced high levels of IFN-gamma, reflecting a T(H)1 response to the parasite, which was apparently sufficient for the immunologic control of the pathogen. Thus, despite their functional activation, CD8+ T lymphocytes do not appear to play a primary role in parasite restraint in the self-curing mouse model of visceral leishmaniasis, as shown using beta2-microglobulin deficient mice which do not produce functional CD8+ T lymphocytes.
Tsagozis
Panagiotis
P
Laboratory of Cellular Immunology, Hellenic Pasteur Institute, 127 Vass. Sofias Ave., 11521 Athens, Greece.
Karagouni
Evdokia
E
Dotsika
Eleni
E
D000818:Animals; D017209:Apoptosis; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology*; D016207:Cytokines / Q000378:metabolism; D005260:Female; D006801:Humans; D018314:Leishmania infantum / Q000276:immunology / Q000472:pathogenicity; D007898:Leishmaniasis, Visceral / Q000276:immunology* / Q000469:parasitology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D054353:Perforin; D052899:Pore Forming Cytotoxic Proteins
D016207:Cytokines; D008562:Membrane Glycoproteins; D052899:Pore Forming Cytotoxic Proteins; D054353:Perforin