Differential expression of var gene groups is associated with morbidity caused by Plasmodium falciparum infection in Tanzanian children.
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.
Rottmann
Matthias
M
Swiss Tropical Institute, Socinstrasse 57, CH 4002 Basel, Switzerland.
Lavstsen
Thomas
T
Mugasa
Joseph Paschal
JP
Kaestli
Mirjam
M
Jensen
Anja T R
AT
Müller
Dania
D
Theander
Thor
T
Beck
Hans-Peter
HP
D000818:Animals; D002675:Child, Preschool; D005260:Female; D014644:Genetic Variation / Q000235:genetics*; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000453:epidemiology* / Q000378:metabolism*; D008297:Male; D009017:Morbidity; D010963:Plasmodium falciparum / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D015800:Protozoan Proteins / Q000096:biosynthesis / Q000235:genetics*; D012720:Severity of Illness Index; D013636:Tanzania
D015800:Protozoan Proteins; C085731:erythrocyte membrane protein 1, Plasmodium falciparum