Studies on Pf332, a major Plasmodium falciparum blood-stage antigen, have largely been hampered by the cross-reactive nature of antibodies generated against the molecule due to its high content of repeats, which are present in other malaria antigens. We previously reported the identification of a conserved domain in Pf332 with a high degree of similarity to the Duffy-binding-like (DBL) domains of the erythrocyte-binding-like (EBL) family. We here describe that antibodies towards Pf332-DBL are induced after repeated exposure to P. falciparum and that they are acquired early in life in areas of intense malaria transmission. Furthermore, a homology model of Pf332-DBL was found to be similar to the structure of the EBL-DBLs. Despite their similarities, antibodies towards Pf332-DBL did not display any cross-reactivity with EBL-proteins as demonstrated by immunofluorescence microscopy, Western blotting, and peptide microarray. Thus the DBL domain is an attractive region to use in further studies on the giant Pf332 molecule.
Identification and Characterization of a Novel Plasmodium falciparum Merozoite Apical Protein Involved in Erythrocyte Binding and Invasion
