Neutrophil depletion exacerbates experimental Chagas' disease in   BALB/c, but protects C57BL/6 mice through modulating the   Th1/Th2 dichotomy in different directions.
To elucidate the roles of neutrophils in experimental Chagas' disease, we depleted the peripheral neutrophils in BALB/c and C57BL/6 mice with a monoclonal antibody 1 day before Trypanosoma cruzi infection. Neutrophil depletion in BALB/ c mice resulted in exacerbation of the disease and decreased expression of mRNA for Th1 cytokines, including IL-2 and IFN-gamma, IL-12p40 and TNF-alpha in their spleens after the infection, while a Th2 cytokine, IL-10, increased especially 1 day after infection. Neutrophils from infected BALB / c mice expressed mRNA for IL-12p40, IFN-gamma, TNF-alpha and Th1 chemoattractive chemokines, monokine induced by IFN-gamma (MIG) and macrophage inflammatory protein-1alpha (MIP-1alpha ). In contrast, in C57BL/6 mice neutrophil depletion induced resistance to the disease and enhanced the expression of the above Th1 cytokines, although IL-10 mRNA in neutrophil-depleted C57BL/6 mice was also higher than in control mice. Neutrophils from C57BL/6 mice did not express IL-12p40, IFN-gamma and MIG but expressed TNF-alpha, MIP-1alpha and IL-10. Therefore, neutrophils may play opposite roles in these two strains of mice with respect to protection versus exacerbation of T. cruzi infection, possibly through modulating the Th1/Th2 dichotomy in different directions.
Department of Immunology and Parasitology, Yamagata University School of Medicine, Yamagata, Japan.
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L
Chen
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Watanabe
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Watanabe
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Sendo
D000818:Animals; D014355:Chagas Disease / Q000276:immunology* / Q000473:pathology; D018925:Chemokines / Q000235:genetics; D016207:Cytokines / Q000235:genetics; D004198:Disease Susceptibility; D005260:Female; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000502:physiology*; D012333:RNA, Messenger / Q000032:analysis; D013154:Spleen / Q000378:metabolism; D018417:Th1 Cells / Q000502:physiology*; D018418:Th2 Cells / Q000502:physiology*
D018925:Chemokines; D016207:Cytokines; D012333:RNA, Messenger