Carvalho Augusto M, Cristal Juqueline R, Muniz Aline C, Carvalho Lucas P, Gomes Regis, Miranda José C, Barral Aldina, Carvalho Edgar M, de Oliveira Camila I
Fundação Oswaldo Cruz, Centro de Pesquisas Gonçalo Moniz.
Serviço de Imunologia, Hospital Universitário Professor Edgard Santos, Universidade Federal da Bahia.
J Infect Dis. 2015 Jul 1;212(1):157-65. doi: 10.1093/infdis/jiv020. Epub 2015 Jan 16.
Leishmaniasis is caused by parasites transmitted to the vertebrate host by infected sand flies. During transmission, the vertebrate host is also inoculated with sand fly saliva, which exerts powerful immunomodulatory effects on the host's immune response.
We conducted a prospective cohort analysis to characterize the human immune response to Lutzomyia intermedia saliva in 264 individuals, from an area for cutaneous leishmaniasis (CL) caused by Leishmania braziliensis.
Antibodies were found in 150 individuals (56.8%); immunoglobulin G1 and G4 were the predominant subclasses. Recall responses to salivary gland sonicate showed elevated production of interleukin 10 (IL-10), interleukin 13, interferon γ, CXCL9, and CCL2 compared with controls. CD4(+)CD25(+) T cells, including Foxp3(+) cells, were the main source of IL-10. L. braziliensis replication was increased (P < .05) in macrophages cocultured with saliva-stimulated lymphocytes from exposed individuals and addition of anti-IL-10 reverted this effect. Positive correlation between antibody response to saliva and cellular response to Leishmania was not found. Importantly, individuals seropositive to saliva are 2.1 times more likely to develop CL (relative risk, 2.1; 95% confidence interval, 1.07-4.2; P < .05).
Exposure to L. intermedia sand flies skews the human immune response, facilitating L. braziliensis survival in vitro, and increases the risk of developing CL.
利什曼病由受感染的白蛉传播给脊椎动物宿主的寄生虫引起。在传播过程中，脊椎动物宿主还会接种白蛉唾液，其对宿主的免疫反应发挥强大的免疫调节作用。
我们进行了一项前瞻性队列分析，以描述来自巴西利什曼原虫引起皮肤利什曼病（CL）地区的264名个体对中间罗蛉唾液的人体免疫反应特征。
在150名个体（56.8%）中发现了抗体；免疫球蛋白G1和G4是主要亚类。与对照组相比，对唾液腺超声提取物的回忆反应显示白细胞介素10（IL-10）、白细胞介素13、干扰素γ、CXCL9和CCL2的产生增加。CD4(+)CD25(+) T细胞，包括Foxp3(+)细胞，是IL-10的主要来源。在与来自暴露个体的唾液刺激淋巴细胞共培养的巨噬细胞中，巴西利什曼原虫的复制增加（P <.05），添加抗IL-10可逆转这种效应。未发现对唾液的抗体反应与对利什曼原虫的细胞反应之间存在正相关。重要的是，唾液血清学阳性的个体患CL的可能性高2.1倍（相对风险，2.1；95%置信区间，1.07 - 4.2；P <.05）。
接触中间罗蛉白蛉会使人体免疫反应发生偏差，促进巴西利什曼原虫在体外存活，并增加患CL的风险。
