Costa S R, D'Oliveira A, Bacellar O, Carvalho E M
Serviço de Imunologia, Universidade Federal da Bahia, Salvador, BA, 40110-160, Brasil.
Mem Inst Oswaldo Cruz. 1999 May-Jun;94(3):367-70. doi: 10.1590/s0074-02761999000300015.
In areas of Leishmania chagasi transmission the ability to control leishmania infection is associated with IFN-gamma production. In visceral leishmaniasis down-regulation of T cell responses is mediated by interleukin-10 (IL-10). In this study we evaluated the lymphoproliferative response, IFN-gamma and IL-10 production on lymphocyte cultures stimulated with recombinant leishmania antigens in subjects with asymptomatic L. chagasi infection. There was a statistically significant difference in the lymphoproliferative response of the subjects with asymptomatic infection as compared to patients with visceral leishmaniasis and healthy subjects with respect to crude antigens (p<0.01), gp-63 (p<0.05) and hsp-70 (p<0. 01), as well as between asymptomatic L. chagasi infected subjects and patients with visceral leishmaniasis with respect to the response to all antigens tested. The IFN-gamma production observed in the group with asymptomatic infection with all the three recombinant antigens tested was higher (p<0.01) than that observed in patients with visceral leishmaniasis and in healthy subjects. Furthermore, in individuals with asymptomatic infection, IL-10 levels in cultures stimulated with recombinant antigens were very low. This study shows that lymphocytes from individuals with asymptomatic L. chagasi infection are able to recognize recombinant leishmania antigens with production of a cytokine that is associated with leishmania killing.
在恰加斯利什曼原虫传播地区，控制利什曼原虫感染的能力与γ干扰素的产生有关。在内脏利什曼病中，T细胞反应的下调由白细胞介素-10（IL-10）介导。在本研究中，我们评估了无症状恰加斯利什曼原虫感染受试者的淋巴细胞培养物在用重组利什曼原虫抗原刺激后的淋巴细胞增殖反应、γ干扰素和IL-10的产生。与内脏利什曼病患者和健康受试者相比，无症状感染受试者对粗抗原（p<0.01）、gp-63（p<0.05）和hsp-70（p<0.01）的淋巴细胞增殖反应存在统计学显著差异，并且无症状恰加斯利什曼原虫感染受试者与内脏利什曼病患者对所有测试抗原的反应之间也存在差异。在无症状感染组中，用所有三种测试重组抗原刺激后观察到的γ干扰素产生量高于内脏利什曼病患者和健康受试者（p<0.01）。此外，在无症状感染个体中，用重组抗原刺激的培养物中的IL-10水平非常低。本研究表明，无症状恰加斯利什曼原虫感染个体的淋巴细胞能够识别重组利什曼原虫抗原，并产生与杀死利什曼原虫相关的细胞因子。
