Leishmania amazonensis: participation of regulatory T and B cells in the in vitro priming (PIV) of CBA/J spleen cells susceptible response.
CBA/J mice are resistant to Leishmania major and susceptible to Leishmania amazonensis. Early events determine infection outcome. Until now, PIV (in vitro priming) immune response to L. amazonensis has not been assessed. Herein, we have shown that compared to L. major, L. amazonensis induced higher parasite burden associated to similar IL-4, IFN-gamma, and TNF-alpha mRNA expressions and IFN-gamma and IL-10 levels. Although similar amounts of IL-10 were detected, the frequency of intracellular IL-10 positive B cells was enhanced in spleen cells stimulated with anti-CD3/anti-CD28, or anti-CD3/anti-CD28 and L. amazonensis, compared to L. major-stimulation. Interestingly, IL-10- producing B cells were reduced in response to anti-CD3/anti-CD28 stimulation combined with L. major compared to the other groups. L. amazonensis may favor T regulatory cell development, since 40% of all the CD4+CD25+ were CD25(high) cells. These data suggest that in PIV, susceptibility to L. amazonensis is not related to Th cell polarization, but to the presence and activity of regulatory T and B cells.
Veras
Patrícia Sampaio Tavares
PS
Laboratório de Patologia e Bio-intervenção, CPqGM, FIOCRUZ/BA, Brazil.
Welby-Borges
Marcus
M
de Santana
Cláudia Dias
CD
Nihei
Jorge
J
Cardillo
Fabiola
F
de Freitas
Luiz Antônio Rodrigues
LA
D000704:Analysis of Variance; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D015870:Gene Expression; D006790:Host-Parasite Interactions / Q000276:immunology; D007041:Hypoxanthine Phosphoribosyltransferase / Q000096:biosynthesis / Q000235:genetics; D007111:Immunity, Cellular; D007371:Interferon-gamma / Q000096:biosynthesis / Q000235:genetics; D016753:Interleukin-10 / Q000096:biosynthesis / Q000235:genetics; D015847:Interleukin-4 / Q000096:biosynthesis / Q000235:genetics; D007894:Leishmania mexicana / Q000276:immunology*; D016773:Leishmaniasis, Cutaneous / Q000276:immunology*; D051379:Mice; D008808:Mice, Inbred CBA; D009569:Nitric Oxide / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013154:Spleen / Q000166:cytology / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics
D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D015847:Interleukin-4; D009569:Nitric Oxide; D007371:Interferon-gamma; D007041:Hypoxanthine Phosphoribosyltransferase