Main content area

Identification of a Novel Antigen of Schistosoma mansoni Shared with Plasmodium falciparum and Evaluation of Different Cross-Reactive Antibody Subclasses Induced by Human Schistosomiasis and Malaria

Pierrot, Christine, Wilson, Shona, Lallet, Hélène, Lafitte, Sophia, Jones, Frances M., Daher, Wassim, Capron, Monique, Dunne, David W., Khalife, Jamal
Infection and immunity 2006 v.74 no.6 pp. 3347-3354
Plasmodium falciparum, Schistosoma mansoni, antibodies, antigens, correlation, genes, humans, immunoglobulins, isotypes, malaria, parasites, schistosomiasis, Kenya, Uganda
Plasmodium falciparum and Schistosoma mansoni are often found in human coinfections, and cross-reactive antibodies to different components of the two parasites have been detected. In this work, we identified a cross-reactive S. mansoni gene product, referred to as SmLRR, that seems to belong to the leucine-rich repeat protein family. Comparative analysis of SmLRR revealed 57% similarity with a putative gene product encoded in the P. falciparum genome. Antibodies to SmLRR were found in experimental infections and in both S. mansoni- and P. falciparum-infected individuals. Correlative analysis of human anti-SmLRR responses in Kenya and Uganda suggested that malaria and schistosomiasis drive the immunoglobulin G3 (IgG3) and IgG4 isotypes, respectively, against SmLRR, suggesting that there is differential regulation of cross-reactive isotypes depending on the infection. In addition, the levels of anti-SmLRR IgG4, but not the levels of IgG3, correlated positively with the intensity of S. mansoni infection.