
DuringTrypanosoma cruziInfection CD1d-Restricted NK T Cells Limit Parasitemia and Augment the Antibody Response to a Glycophosphoinositol-Modified Surface Protein
Author(s) -
Malcolm S. Duthie,
Monika Wleklinski-Lee,
Sherilyn Smith,
Toshinori Nakayama,
Masaru Taniguchi,
Stuart J. Kahn
Publication year - 2002
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.70.1.36-48.2002
Subject(s) - parasitemia , biology , trypanosoma cruzi , immunology , antibody , chagas disease , immune system , interleukin 12 , interleukin 21 , cytotoxic t cell , interferon gamma , t cell , in vitro , parasite hosting , plasmodium falciparum , malaria , biochemistry , world wide web , computer science
Trypanosoma cruzi is a protozoan parasite that chronically infects many mammalian species and in humans causes Chagas' disease, a chronic inflammatory disease. The parasite expresses glycophosphoinositol (GPI), which potently stimulates interleukin 12 (IL-12) production. During T. cruzi infection IL-12, and possibly GPI, might stimulate NK T cells to affect the protective and chronic inflammatory responses. Here we report that during T. cruzi infection CD1d-restricted NK T cells are stimulated as NK T-cell-deficient mice have greater parasitemia. Furthermore, during T. cruzi infection the percentages of NK T cells in the liver and spleen become decreased for prolonged periods of time, and in vitro stimulation of NK T cells derived from livers of chronically infected mice, compared to uninfected mice, results in increased gamma interferon and IL-4 secretion. Moreover, in NK T-cell-deficient mice the chronic-phase antibody response to a GPI-modified surface protein is decreased. These results indicate that, during the acute infection, NK T cells limit parasitemia and that, during the chronic phase, NK T cells augment the antibody response. Thus, during T. cruzi infection the quality of an individual's NK T-cell response can affect the level of parasitemia and parasite tissue burden, the intensity of the chronic inflammatory responses, and possibly the outcome of Chagas' disease.