Molecular and immunological characterization of selected Plasmodium falciparum gametocyte-specific genes

Objective The increasing emergence of drug-resistant malaria parasites highlights the need for new interventions to eliminate malaria. Vaccines would be appropriate; however, the functions of many parasite components are unknown. This study sought to identify proteins that could serve as good antigens for vaccine development. Methods Two genes encoding components crucial to the parasite’s survival and with a chance to be found on the parasite’s surface were selected from existing databases. Analysis of their DNA sequences from the Pf3K database was done and their mRNA quantified. Peptides corresponding to predicted antibody-binding sites on the protein sequences were purchased and are being used for immunological investigations. Results The selected genes were conserved across countries in Africa and South East Asia. Sequencing of total mRNA of field isolate parasites revealed that one of the genes (Pf3D7_0513000) is expressed mostly in gametocytes (playing key role in disease transmission) while the other one, Pf3D_115800 is expressed in the gametocytes and other stages. The findings of this study were consistent with observations with laboratory strains. Conclusion The conserved nature of the genes and their expression in gametocytes are an indication that they could be potential candidates for transmission blocking vaccines. However, findings from immunological work are valuable to confirm this assertion.