Rottmann Matthias, Lavstsen Thomas, Mugasa Joseph Paschal, Kaestli Mirjam, Jensen Anja T R, Müller Dania, Theander Thor, Beck Hans-Peter
Swiss Tropical Institute, Socinstrasse 57, CH 4002 Basel, Switzerland.
Infect Immun. 2006 Jul;74(7):3904-11. doi: 10.1128/IAI.02073-05.
The var gene family of Plasmodium falciparum encodes the variant surface antigen Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1). PfEMP1 is considered an important pathogenicity factor in P. falciparum infection because it mediates cytoadherence to host cell endothelial receptors. var genes can be grouped into three major groups, A, B, and C, and the conserved var genes, var1-4, according to sequence similarities in coding and noncoding upstream regions. Using real-time quantitative PCR in a study conducted in Tanzania, the var transcript abundances of the different var gene groups were compared among patients with severe, uncomplicated, and asymptomatic malaria. Transcripts of var group A and B genes were more abundant in patients with severe malaria than in patients with uncomplicated malaria. In general, the transcript abundances of var group A and B genes were higher for children with clinical malaria than for children with asymptomatic infections. The var group C and var1-like transcript abundances were similar between the three sample groups. A transcript abundance pattern similar to that for var group A was observed for var2csa and var3-like genes. These results suggest that substantial and systematic differences in var gene expression exist between different clinical presentations.
恶性疟原虫的var基因家族编码变异表面抗原恶性疟原虫红细胞膜蛋白1（PfEMP1）。PfEMP1被认为是恶性疟原虫感染中的一个重要致病因素，因为它介导与宿主细胞内皮受体的细胞黏附。根据编码区和非编码上游区域的序列相似性，var基因可分为A、B和C三大组，以及保守的var基因var1 - 4。在坦桑尼亚进行的一项研究中，使用实时定量PCR比较了重症、非复杂性和无症状疟疾患者中不同var基因组的转录本丰度。A组和B组var基因的转录本在重症疟疾患者中比在非复杂性疟疾患者中更为丰富。总体而言，临床疟疾患儿中A组和B组var基因的转录本丰度高于无症状感染患儿。三个样本组之间C组var基因和var1样转录本丰度相似。对于var2csa和var3样基因，观察到了与A组var基因相似的转录本丰度模式。这些结果表明，不同临床表现之间var基因表达存在显著的系统性差异。
