Novel malaria antigen Plasmodium yoelii E140 induces antibody-mediated sterile protection in mice against malaria challenge

Emily C. Smith, Keith J. Limbach, Nonenipha Rangel, Kyosuke Oda, Jessica S. Bolton, Mengyan Du, Kalpana Gowda, Jianyang Wang, J. Kathleen Moch, Sharvari Sonawane, Rachel Velasco, Arnel Belmonte (+10 others)
2020 PLoS ONE  
Only a small fraction of the antigens expressed by malaria parasites have been evaluated as vaccine candidates. A successful malaria subunit vaccine will likely require multiple antigenic targets to achieve broad protection with high protective efficacy. Here we describe protective efficacy of a novel antigen, Plasmodium yoelii (Py) E140 (PyE140), evaluated against P. yoelii challenge of mice. Vaccines targeting PyE140 reproducibly induced up to 100% sterile protection in both inbred and
more » ... h inbred and outbred murine challenge models. Although PyE140 immunization induced high frequency and multifunctional CD8+ T cell responses, as well as CD4+ T cell responses, protection was mediated by PyE140 antibodies acting against blood stage parasites. Protection in mice was long-lasting with up to 100% sterile protection at twelve weeks post-immunization and durable high titer anti-PyE140 antibodies. The E140 antigen is expressed in all Plasmodium species, is highly conserved in both P. falciparum lab-adapted strains and endemic circulating parasites, and is thus a promising lead vaccine candidate for future evaluation against human malaria parasite species.
doi:10.1371/journal.pone.0232234 pmid:32407410 fatcat:tyhta56c55aobnkjqzlfmdo4b4