Modulation of immune responses by Plasmodium falciparum infection in asymptomatic children living in the endemic region of Mbita, western Kenya
Modulation of immune responses by Plasmodium falciparum infection in asymptomatic children living in the endemic region of Mbita, western Kenya
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恶性疟原虫感染对肯尼亚西部姆比塔流行区无症状儿童免疫反应的调节
DOI：
10.1016/j.parint.2018.01.001
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发表时间：
2018
影响因子：
1.9
通讯作者：
Yui Katsuyuki
中科院分区：
文献类型：
--
作者：
Kijogi Caroline;Kimura Daisuke;Bao Lam Quoc;Nakamura Risa;Chadeka Evans Asena;Cheruiyot Ngetich Benard;Bahati Felix;Yahata Kazuhide;Kaneko Osamu;Njenga Sammy M.;Ichinose Yoshio;Hamano Shinjiro;Yui Katsuyuki
生活在疟疾流行地区的个人在经过一段时间的多次再感染后，在临床上具有免疫力，并在没有明显症状的情况下保持感染状态。然而，目前尚不清楚为什么需要很长时间才能获得对疟疾的临床免疫力，以及这种免疫力是如何维持的。虽然据报道疟疾感染会引起免疫反应的抑制，但对生活在疟疾流行地区的无症状个体的研究相对较少。我们对生活在肯尼亚恶性疟原虫和曼氏血吸虫感染共同流行地区的4-16岁无症状学龄儿童的免疫应答进行了横断面研究。对外周血单核细胞进行流式细胞术分析并培养以确定增殖反应和细胞因子产生。P.在显微镜水平上，恶性疟原虫感染的儿童与阴性儿童相似，除了中央记忆表型CD 8 +T细胞和自然杀伤细胞减少。在功能研究中，外周血单个核细胞对P。恶性疟原虫粗抗原在儿童中表现出很强的异质性。此外，抗CD 3和抗CD 28单克隆抗体诱导的IL-2产生在P中显著降低。恶性疟原虫阳性儿童相比，阴性儿童，这表明无反应的状态。这些数据表明，T细胞免疫反应的质量是异质性的无症状儿童生活在流行地区的P。恶性疟原虫感染后，这些反应通常会受到疟原虫感染的抑制。
Individuals living in malaria endemic areas become clinically immune after multiple re-infections over time and remain infected without apparent symptoms. However, it is unclear why a long period is required to gain clinical immunity to malaria, and how such immunity is maintained. Although malaria infection is reported to induce inhibition of immune responses, studies on asymptomatic individuals living in endemic regions of malaria are relatively scarce. We conducted a cross-sectional study of immune responses in asymptomatic school children aged 4–16 years living in an area wherePlasmodium falciparumandSchistosoma mansoniinfections are co-endemic in Kenya. Peripheral blood mononuclear cells were subjected to flow cytometric analysis and cultured to determine proliferative responses and cytokine production. The proportions of cellular subsets in children positive forP. falciparuminfection at the level of microscopy were comparable to the negative children, except for a reduction in central memory-phenotype CD8+T cells and natural killer cells. In functional studies, the production of cytokines by peripheral blood mononuclear cells in response toP. falciparumcrude antigens exhibited strong heterogeneity among children. In addition, production of IL-2 in response to anti-CD3 and anti-CD28 monoclonal antibodies was significantly reduced inP. falciparum-positive children as compared to -negative children, suggesting a state of unresponsiveness. These data suggest that the quality of T cell immune responses is heterogeneous among asymptomatic children living in the endemic region ofP. falciparum, and that the responses are generally suppressed by active infection withPlasmodiumparasites.