Beeson James G, Brown Graham V
Department of Medicine, University of Melbourne, Royal Melbourne Hospital, Victoria, Australia.
J Infect Dis. 2004 Jan 15;189(2):169-79. doi: 10.1086/380975. Epub 2004 Jan 6.
Hyaluronic acid (HA) and chondroitin sulfate A (CSA) have been identified as receptors for adhesion of Plasmodium falciparum-infected erythrocytes (IEs) and appear to be involved in mediating parasite accumulation in the placenta. We demonstrate here that some, but not all, parasite populations can adhere to both receptors, and we identify distinguishing features of adhesion. Adhesion to HA and CSA was greatest among pigmented trophozoite-infected erythrocytes and at physiologic pH and was associated with a lack of rosette formation and little adhesion to CD36 and intercellular adhesion molecule-1. Adhesion to HA was sensitive to trypsin cleavage of the IE surface, whereas trypsin-resistant and trypsin-sensitive CSA adhesion were both observed. Soluble HA, but not CSA, could cause aggregation or clumping of IEs. Different HA types varied in adhesion-inhibitory activity, which was altered by physical treatment, suggesting that structural features of HA influence IE interactions. These findings have important implications for understanding the pathogenesis of malaria, particularly in pregnancy.
透明质酸（HA）和硫酸软骨素A（CSA）已被确定为恶性疟原虫感染红细胞（IEs）黏附的受体，似乎参与介导寄生虫在胎盘内的聚集。我们在此证明，部分而非全部寄生虫群体能够黏附于这两种受体，并且我们确定了黏附的显著特征。在色素滋养体感染的红细胞中，在生理pH值条件下，对HA和CSA的黏附最为显著，且与玫瑰花结形成的缺乏以及对CD36和细胞间黏附分子-1的少量黏附相关。对HA的黏附对IE表面的胰蛋白酶切割敏感，而对CSA的黏附则观察到既有抗胰蛋白酶的情况，也有对胰蛋白酶敏感的情况。可溶性HA而非CSA可导致IEs聚集或结块。不同类型的HA在黏附抑制活性方面存在差异，这种活性会因物理处理而改变，这表明HA的结构特征会影响IE的相互作用。这些发现对于理解疟疾的发病机制具有重要意义，尤其是在妊娠疟疾中。
