Institute of Tropical Medicine, University of Tübingen, Tübingen, Germany.
School of Health Sciences, Kirinyaga University, Kerugoya, Kenya.
Sci Rep. 2019 Feb 8;9(1):1709. doi: 10.1038/s41598-018-38175-1.
Plasmodium falciparum histidine-rich proteins 2 (PfHRP2) based RDTs are advocated in falciparum malaria-endemic regions, particularly when quality microscopy is not available. However, diversity and any deletion in the pfhrp2 and pfhrp3 genes can affect the performance of PfHRP2-based RDTs. A total of 400 samples collected from uncomplicated malaria cases from Kenya were investigated for the amino acid repeat profiles in exon 2 of pfhrp2 and pfhrp3 genes. In addition, PfHRP2 levels were measured in 96 individuals with uncomplicated malaria. We observed a unique distribution pattern of amino acid repeats both in the PfHRP2 and PfHRP3. 228 PfHRP2 and 124 PfHRP3 different amino acid sequences were identified. Of this, 214 (94%) PfHRP2 and 81 (65%) PfHRP3 amino acid sequences occurred only once. Thirty-nine new PfHRP2 and 20 new PfHRP3 amino acid repeat types were identified. PfHRP2 levels were not correlated with parasitemia or the number of PfHRP2 repeat types. This study shows the variability of PfHRP2, PfHRP3 and PfHRP2 concentration among uncomplicated malaria cases. These findings will be useful to understand the performance of PfHRP2-based RDTs in Kenya.
恶性疟原虫组氨酸丰富蛋白 2（PfHRP2）基于 RDT 在恶性疟流行地区被推荐使用，特别是在无法获得高质量显微镜检查的情况下。然而，pfhrp2 和 pfhrp3 基因中的多样性和任何缺失都可能影响基于 PfHRP2 的 RDT 的性能。本研究共检测了来自肯尼亚无并发症疟疾患者的 400 份样本，以调查 pfhrp2 和 pfhrp3 基因外显子 2 中的氨基酸重复谱。此外，还测量了 96 名无并发症疟疾患者的 PfHRP2 水平。我们观察到 PfHRP2 和 PfHRP3 中均存在独特的氨基酸重复分布模式。鉴定出 228 种 PfHRP2 和 124 种 PfHRP3 不同的氨基酸序列。其中，214 种（94%）PfHRP2 和 81 种（65%）PfHRP3 氨基酸序列仅出现一次。鉴定出 39 种新的 PfHRP2 和 20 种新的 PfHRP3 氨基酸重复类型。PfHRP2 水平与寄生虫血症或 PfHRP2 重复类型的数量无关。本研究表明了无并发症疟疾患者中 PfHRP2、PfHRP3 和 PfHRP2 浓度的变异性。这些发现将有助于了解基于 PfHRP2 的 RDT 在肯尼亚的性能。
