Malaria is an infectious disease affecting humans, which is transmitted by the bite of Anopheles mosquitoes harboring sporozoites of parasitic protozoans belonging to the genus Plasmodium. Despite past achievements to control the protozoan disease, malaria still remains a significant health threat up to now. In this study, we cloned and characterized the full-unit Plasmodium yoelii genes encoding merozoite surface protein 1 (MSP1), circumsporozoite protein (CSP), and Duffy-binding protein (DBP), each of which can be applied for investigations to obtain potent protective vaccines in the rodent malaria model, due to their specific expression patterns during the parasite life cycle. Recombinant fragments corresponding to the middle and C-terminal regions of PyMSP1 and PyCSP, respectively, displayed strong reactivity against P. yoelii-infected mice sera. Specific native antigens invoking strong humoral immune response during the primary and secondary infections of P. yoelii were also abundantly detected in experimental ICR mice. The low or negligible parasitemia observed in the secondary infected mice was likely to result from the neutralizing action of the protective antibodies. Identification of these antigenic proteins might provide the necessary information and means to characterize additional vaccine candidate antigens, selected solely on their ability to produce the protective antibodies.
Bibliographical noteFunding Information:
This research was supported by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health and Welfare, the Republic of Korea (grant no. HI15C3050).
© 2017, Korean Society for Parasitology and Tropical Medicine.
- Plasmodium yoelii
- Protective immunity
- Rodent malaria model
- Vaccine candidate