A Multivalent Peptide Vaccine Against Malaria, Targeting Plasmodium Circumsporozoite Protein and Mosquito AgTRIO.

Malaria begins when an infected mosquito injects saliva containing Plasmodium sporozoites into the host skin. The immune response against a mosquito saliva protein, AgTRIO, reduces Plasmodium infection and can work in combination with antibody against the Plasmodium circumsporozoite protein (CSP). We have now developed a chimeric peptide, PfAg, containing regions from Plasmodium falciparum CSP (PfCSP) and AgTRIO. Mice administered PfAg generated robust humoral responses against both PfCSP and AgTRIO. After exposure to PfCSP-expressing Plasmodium berghei-infected mosquitoes, PfAg-immunized inbred C57BL/6 and outbred CD-1 mice had significantly improved survival compared with control animals. These data will aid in the development of a new malaria vaccine.