Lennartz Frank, Adams Yvonne, Bengtsson Anja, Olsen Rebecca W, Turner Louise, Ndam Nicaise T, Ecklu-Mensah Gertrude, Moussiliou Azizath, Ofori Michael F, Gamain Benoit, Lusingu John P, Petersen Jens E V, Wang Christian W, Nunes-Silva Sofia, Jespersen Jakob S, Lau Clinton K Y, Theander Thor G, Lavstsen Thomas, Hviid Lars, Higgins Matthew K, Jensen Anja T R
Department of Biochemistry, University of Oxford, South Parks Road, OX1 3QU Oxford, UK.
Centre for Medical Parasitology, Department of Immunology and Microbiology (ISIM), Faculty of Health and Medical Sciences, University of Copenhagen, 1165 Copenhagen, Denmark; Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), 2100 Copenhagen, Denmark.
Cell Host Microbe. 2017 Mar 8;21(3):403-414. doi: 10.1016/j.chom.2017.02.009.
Cerebral malaria is a deadly outcome of infection by Plasmodium falciparum, occurring when parasite-infected erythrocytes accumulate in the brain. These erythrocytes display parasite proteins of the PfEMP1 family that bind various endothelial receptors. Despite the importance of cerebral malaria, a binding phenotype linked to its symptoms has not been identified. Here, we used structural biology to determine how a group of PfEMP1 proteins interacts with intercellular adhesion molecule 1 (ICAM-1), allowing us to predict binders from a specific sequence motif alone. Analysis of multiple Plasmodium falciparum genomes showed that ICAM-1-binding PfEMP1s also interact with endothelial protein C receptor (EPCR), allowing infected erythrocytes to synergistically bind both receptors. Expression of these PfEMP1s, predicted to bind both ICAM-1 and EPCR, is associated with increased risk of developing cerebral malaria. This study therefore reveals an important PfEMP1-binding phenotype that could be targeted as part of a strategy to prevent cerebral malaria.
脑型疟疾是恶性疟原虫感染导致的致命后果,当被寄生虫感染的红细胞在大脑中积聚时就会发生。这些红细胞展示出与多种内皮受体结合的PfEMP1家族寄生虫蛋白。尽管脑型疟疾很重要,但尚未确定与其症状相关的结合表型。在这里,我们利用结构生物学来确定一组PfEMP1蛋白如何与细胞间黏附分子1(ICAM-1)相互作用,从而使我们仅从特定序列基序就能预测结合物。对多个恶性疟原虫基因组的分析表明,与ICAM-1结合的PfEMP1也与内皮蛋白C受体(EPCR)相互作用,使受感染的红细胞能够协同结合这两种受体。预计能同时结合ICAM-1和EPCR的这些PfEMP1的表达与患脑型疟疾风险增加有关。因此,这项研究揭示了一种重要的PfEMP1结合表型,可作为预防脑型疟疾策略的一部分加以靶向作用。