Discovery of novel blood-stage malaria vaccine candidates based on the molecular function

2016 Fiscal Year Final Research Report

• Project/Area Number: 26253026
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Parasitology (including sanitary zoology)
• Research Institution: Ehime University
• Principal Investigator: TSUBOI Takafumi 愛媛大学, プロテオサイエンスセンター, 教授 (00188616)
• Co-Investigator(Kenkyū-buntansha): 高島 英造 愛媛大学, プロテオサイエンスセンター, 准教授 (50366762)
• Research Collaborator: MORITA Masayuki 愛媛大学, プロテオサイエンスセンター, 研究員 (60709632)
• Project Period (FY): 2014-06-27 – 2017-03-31
• Keywords: マラリア / 赤血球期ワクチン / コムギ無細胞法

Outline of Final Research Achievements

In order to identify novel blood-stage malaria vaccine candidates of Plasmodium falciparum, we have expressed 142 putative merozoite specific recombinant proteins. Among them, 34 bounded to the RBC surface. We then analyzed extent of polymorphism in four promising RBC-binding proteins, PfRipr, PfRALP1, PfGAMA, and PfMSPDBL1 using clinical isolates from a region of high malaria transmission in Uganda. PfRipr gene was most highly conserved among the four genes investigated. In addition, we expressed recombinant proteins for the four candidates based on P. falciparum laboratory strain 3D7 sequences, immunized rabbits to obtain specific antibodies and performed functional growth inhibition assay (GIA) on the heterologous FVO parasite strain. The GIA activity of anti-PfRipr antibody was highest among the four antibodies even on the polymorphic FVO parasite strain. Thus, PfRipr is regarded as a promising blood-stage malaria vaccine against P. falciparum.

Free Research Field

医歯薬学