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Updated: May 23, 2026
A Multi-detection Assay for Malaria Transmitting Mosquitoes
Published on: February 28, 2015
Prognostic indicators of life-threatening malaria are associated with distinct parasite variant antigen profiles
George M Warimwe1, Gregory Fegan, Jennifer N Musyoki
1Kenya Medical Research Institute-Wellcome Trust Research Programme, P. O. Box 230-80108 Kilifi, Kenya.
Abstract:
PfEMP1 is a family of cytoadhesive surface antigens expressed on erythrocytes infected with Plasmodium falciparum, the parasite that causes the most severe form of malaria. These surface antigens play a role in immune evasion and are thought to contribute to the pathogenesis of the malaria parasite. Previous studies have suggested a role for a specific subset of PfEMP1 called "group A" in severe malaria. To explore the role of group A PfEMP1 in disease, we measured the expression of the var genes that encode them in parasites from clinical isolates collected from children suffering from malaria. We also looked at the ability of these clinical isolates to induce rosetting of erythrocytes, which indicates a cytoadhesion phenotype that is thought to be important in pathogenesis. These two sets of data were correlated with the presence of two life-threatening manifestations of severe malaria in the children: impaired consciousness and respiratory distress. Using regression analysis, we show that marked rosetting was associated with respiratory distress, whereas elevated expression of group A-like var genes without elevated rosetting was associated with impaired consciousness. The results suggest that manifestations of malarial disease may reflect the distribution of cytoadhesion phenotypes expressed by the infecting parasite population.
Insights
Severe malaria manifestations in children are linked to Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) variants. Rosetting is associated with respiratory distress, while specific var gene expression correlates with impaired consciousness.
Area of Science:
- Malariology
- Immunology
- Pathogenesis
Background:
- Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) antigens mediate cytoadhesion and immune evasion.
- Group A PfEMP1 variants are implicated in severe malaria pathogenesis.
- Understanding PfEMP1's role in disease manifestations is crucial for malaria control.
Purpose of the Study:
- To investigate the association between var gene expression, erythrocyte rosetting, and severe malaria complications in children.
- To explore the differential roles of PfEMP1 cytoadhesion phenotypes in distinct severe malaria manifestations.
Main Methods:
- Analysis of var gene expression in clinical Plasmodium falciparum isolates from children with malaria.
- Assessment of erythrocyte rosetting induced by these isolates.
- Correlation of rosetting and var gene expression with impaired consciousness and respiratory distress using regression analysis.
Main Results:
- Marked erythrocyte rosetting was significantly associated with respiratory distress.
- Elevated expression of group A-like var genes, without marked rosetting, correlated with impaired consciousness.
- Distinct cytoadhesion phenotypes of the infecting parasite population were linked to specific severe malaria symptoms.
Conclusions:
- Severe malaria manifestations may be determined by the specific cytoadhesion phenotypes expressed by the infecting Plasmodium falciparum population.
- This suggests that parasite tropism and virulence are modulated by PfEMP1 expression profiles.
- Targeting specific PfEMP1 variants or their associated cytoadhesion mechanisms could offer new therapeutic strategies for severe malaria.
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