Fund for Scientific Research FNRS, Brussels, Belgium.
Research Institute of Health and Society, Université catholique de Louvain, Brussels, Belgium.
JCI Insight. 2020 Jan 16;5(1):130769. doi: 10.1172/jci.insight.130769.
BACKGROUNDSerological tools for the accurate detection of recent malaria exposure are needed to guide and monitor malaria control efforts. IgG responses against Plasmodium vivax and P. falciparum merozoite surface protein-10 (MSP10) were measured as a potential way to identify recent malaria exposure in the Peruvian Amazon.METHODSA field-based study included 470 participants in a longitudinal cohort who completed a comprehensive evaluation: light microscopy and PCR on enrollment, at least 1 monthly follow-up by light microscopy, a second PCR, and serum and dried blood spots for serological analysis at the end of the follow-up. IgG titers against novel mammalian cell-produced recombinant PvMSP10 and PfMSP10 were determined by ELISA.RESULTSDuring the follow-up period, 205 participants were infected, including 171 with P. vivax, 26 with P. falciparum, 6 with infections by both species but at different times, and 2 with mixed infections. Exposure to P. vivax was more accurately identified when serological responses to PvMSP10 were obtained from serum (sensitivity, 58.1%; specificity, 81.8%; AUC: 0.76) than from dried blood spots (sensitivity, 35.2; specificity, 83.5%; AUC: 0.64) (PAUC < 0.001). Sensitivity was highest (serum, 82.9%; dried blood spot, 45.7%) with confirmed P. vivax infections occurring 7-30 days before sample collection; sensitivity decreased significantly in relation to time since last documented infection. PvMSP10 serological data did not show evidence of interspecies cross-reactivity. Anti-PfMSP10 responses poorly discriminated between P. falciparum-exposed and nonexposed individuals (AUC = 0.59; P > 0.05).CONCLUSIONAnti-PvMSP10 IgG indicates recent exposure to P. vivax at the population level in the Amazon region. Serum, not dried blood spots, should be used for such serological tests.FUNDINGCooperative agreement U19AI089681 from the United States Public Health Service, NIH/National Institute of Allergy and Infectious Diseases, as the Amazonian International Center of Excellence in Malaria Research.
为了指导和监测疟疾控制工作，需要使用血清学工具来准确检测近期疟原虫暴露情况。本研究旨在评估新的哺乳动物细胞表达的重组蛋白（PvMSP10 和 PfMSP10）的 IgG 反应，作为一种在秘鲁亚马逊地区识别近期疟疾感染的方法。
这是一项基于现场的研究，纳入了 470 名参加纵向队列的参与者，他们完成了全面评估：入组时进行光镜检查和 PCR，至少每月通过光镜检查进行一次随访，第二次 PCR，以及在随访结束时进行血清和干血斑的血清学分析。通过 ELISA 测定针对新型哺乳动物细胞表达的重组 PvMSP10 和 PfMSP10 的 IgG 滴度。
在随访期间，有 205 名参与者感染，包括 171 名感染 P. vivax、26 名感染 P. falciparum、6 名同时感染两种不同时间的疟原虫以及 2 名混合感染。与从干血斑获得的 PvMSP10 血清学反应（敏感性 58.1%，特异性 81.8%，AUC：0.76）相比，P. vivax 感染的检测更准确（血清，敏感性 58.1%，特异性 81.8%，AUC：0.76）（PAUC<0.001）。在采集样本前 7-30 天确诊的 P. vivax 感染中，敏感性最高（血清，82.9%；干血斑，45.7%）；与上次有记录的感染时间间隔越长，敏感性显著下降。PvMSP10 血清学数据未显示种间交叉反应的证据。抗 PfMSP10 反应不能很好地区分暴露于 PfMSP10 和未暴露于 PfMSP10 的个体（AUC=0.59；P>0.05）。
抗 PvMSP10 IgG 表明在亚马逊地区人群中存在近期感染 P. vivax 的情况。血清，而不是干血斑，应用于此类血清学检测。
美国公共卫生服务署、NIH/National Institute of Allergy and Infectious Diseases 合作协议 U19AI089681 作为亚马逊国际疟疾研究卓越中心提供的资金支持。
