Development of a Chimeric Plasmodium berghei Strain Expressing the Repeat Region of the P. vivax Circumsporozoite Protein for In Vivo Evaluation of Vaccine Efficacy

Authors

Diego A. Espinosa, Johns Hopkins University
Anjali Yadava, Walter Reed Army Institute of Research
Evelina Angov, Walter Reed Army Institute of Research
Paul L. Maurizio, Johns Hopkins University
Christian F. Ockenhouse, Walter Reed Army Institute of Research
Fidel Zavala, Walter Reed Army Institute of ResearchFollow

Date of this Version

2013

Citation

Published in Infection and Immunity (2013) 81(8): 2882-2887. DOI:10.1128/IAI.00461-13

Abstract

The development of vaccine candidates against Plasmodium vivax—the most geographically widespread human malaria species— is challenged by technical difficulties, such as the lack of in vitro culture systems and availability of animal models. Chimeric rodent Plasmodium parasites are safe and useful tools for the preclinical evaluation of new vaccine formulations. We report the successful development and characterization of chimeric Plasmodium berghei parasites bearing the type I repeat region of P. vivax circumsporozoite protein (CSP). The P. berghei-P. vivax chimeric strain develops normally in mosquitoes and produces highly infectious sporozoites that produce patent infection in mice that are exposed to the bites of as few as 3 P. berghei-P. vivax-infected mosquitoes. Using this transgenic parasite, we demonstrate that monoclonal and polyclonal antibodies against P. vivax CSP strongly inhibit parasite infection and thus support the notion that these antibodies play an important role in protective immunity. The chimeric parasites we developed represent a robust model for evaluating protective immune responses against P. vivax vaccines based on CSP.