加纳南部无症状儿童中抗 MSP3 和 Pfs230 抗体反应及感染多样性的动态。
Dynamics of anti-MSP3 and Pfs230 antibody responses and multiplicity of infection in asymptomatic children from southern Ghana.
机构信息
Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana.
School of Medical Sciences, University of Cape Coast, Cape Coast, Ghana.
出版信息
Parasit Vectors. 2018 Jan 5;11(1):13. doi: 10.1186/s13071-017-2607-5.
BACKGROUND
During a Plasmodium infection, exposure of human host immune cells to both the asexual and the sexual stages of the parasite elicit immune responses. These responses may be protective and prevent the development of high parasitaemia and its associated clinical symptoms, or block the transmission of malaria to an uninfected person. This study aimed at examining the dynamics of naturally acquired immune responses against the asexual and sexual forms of Plasmodium falciparum as well as assessing differences in the multiplicity of infection (MOI) in asymptomatic Ghanaian children living in two communities with varying malaria transmission intensities.
METHODS
School children aged between 6 and 12 years were recruited from Obom, a high malaria prevalence setting and Abura, a low malaria prevalence setting and enrolled in monthly multiple cross sectional surveys between February and May 2015. Filter paper blood blots (DBS) as well as thick and thin blood smears were made from finger-pricked blood at each visit. Plasmodium falciparum parasite prevalence was determined by microscopy and PCR. Serum eluted from the DBS were used to assess anti-Pfs230 (sexual stage) and anti-MSP3 (asexual stage) antibody levels using indirect ELISA and DNA extracted from the DBS used to assess MOI.
RESULTS
Malaria parasite point prevalence and MOI throughout the study was higher in Obom than Abura. The trend of parasite prevalence estimated by microscopy was similar to that determined by PCR in Obom but not in Abura. The trend of MSP3 antibody seroprevalence followed that of PCR-estimated parasite prevalence in Obom, while in Abura the trend of Pfs230 antibody seroprevalence followed that of PCR-estimated parasite prevalence.
CONCLUSIONS
Microscopy can more accurately predict changes in parasite prevalence in high transmission settings than low transmission settings. In high transmission settings, P. falciparum parasite prevalence can predict antibody seroprevalence to MSP3, whilst in low transmission settings, seroprevalence against Pfs230 may be a useful predictor of parasite prevalence.
背景
在疟原虫感染期间，人体免疫细胞暴露于寄生虫的无性和有性阶段会引发免疫反应。这些反应可能具有保护作用，可防止高疟原虫血症及其相关临床症状的发生，或阻止疟疾向未感染者传播。本研究旨在检查针对恶性疟原虫无性和有性形式的自然获得性免疫反应的动态，并评估生活在疟疾传播强度不同的两个社区的无症状加纳儿童中的多重感染（MOI）的差异。
方法
2015 年 2 月至 5 月期间，从疟疾高流行地区的 Obom 和疟疾低流行地区的 Abura 招募了 6 至 12 岁的在校儿童，并每月进行多次横断面调查。在每次就诊时，从刺破手指采集的血样中制作滤纸血斑（DBS）以及厚、薄血涂片。通过显微镜检查和 PCR 确定恶性疟原虫寄生虫的流行率。从 DBS 洗脱的血清用于通过间接 ELISA 评估针对 Pf s230（有性阶段）和 MSP3（无性阶段）的抗体水平，从 DBS 中提取的 DNA 用于评估 MOI。
结果
在整个研究期间，Obom 的疟疾寄生虫点流行率和 MOI 均高于 Abura。Obom 中通过显微镜估计的寄生虫流行趋势与 PCR 确定的趋势相似，但在 Abura 中则不然。在 Obom 中，MSP3 抗体血清阳性率的趋势与 PCR 估计的寄生虫流行率一致，而在 Abura 中，Pf s230 抗体血清阳性率的趋势与 PCR 估计的寄生虫流行率一致。
结论
在高传播地区，显微镜比低传播地区更能准确预测寄生虫流行率的变化。在高传播地区，恶性疟原虫寄生虫流行率可预测 MSP3 的抗体血清阳性率，而在低传播地区，Pf s230 的血清阳性率可能是寄生虫流行率的有用预测指标。
Zotero 插件