Demonstration of specific binding of heparin to Plasmodium falciparum-infected vs. non-infected red blood cells by single-molecule force spectroscopy
Demonstration of specific binding of heparin to Plasmodium falciparum-infected vs. non-infected red blood cells by single-molecule force spectroscopy
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DOI：
10.1039/c2nr32821f
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发表时间：
2013-01-01
期刊：
影响因子：
6.7
通讯作者：
Fernandez-Busquets, Xavier
中科院分区：
文献类型：
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作者：
Jose Valle-Delgado, Juan;Urban, Patricia;Fernandez-Busquets, Xavier
糖胺聚糖（GAG）在不同组织的微血管内皮中隔离恶性疟原虫感染的红细胞（pRBC）以及在感染和未感染的红细胞（RBC）之间形成小簇（roblast）中起重要作用。隔离和玫瑰花结被认为是严重疟疾的特征事件。在这里，我们使用肝素和被恶性疟原虫3D 7株感染的pRBC作为研究GAG-pRBC相互作用的模型。荧光显微镜和荧光辅助细胞分选试验表明，外源性加入的肝素对pRBC（优先用于感染晚期寄生虫的那些）与RBC具有结合特异性。肝素-pRBC粘附已探测单分子力光谱，获得的平均结合力范围在28和46 pN之间，这取决于加载速率。在对照实验中未观察到肝素与未感染RBC的显著结合。这项工作代表了第一种在单个分子水平上定量评价GAG-pRBC分子相互作用的方法。
Glycosaminoglycans (GAGs) play an important role in the sequestration of Plasmodium falciparum-infected red blood cells (pRBCs) in the microvascular endothelium of different tissues, as well as in the formation of small clusters (rosettes) between infected and non-infected red blood cells (RBCs). Both sequestration and rosetting have been recognized as characteristic events in severe malaria. Here we have used heparin and pRBCs infected by the 3D7 strain of P. falciparum as a model to study GAG-pRBC interactions. Fluorescence microscopy and fluorescence-assisted cell sorting assays have shown that exogenously added heparin has binding specificity for pRBCs (preferentially for those infected with late forms of the parasite) vs. RBCs. Heparin-pRBC adhesion has been probed by single-molecule force spectroscopy, obtaining an average binding force ranging between 28 and 46 pN depending on the loading rate. No significant binding of heparin to non-infected RBCs has been observed in control experiments. This work represents the first approach to quantitatively evaluate GAG-pRBC molecular interactions at the individual molecule level.