Identification of two new protective pre-erythrocytic malaria vaccine antigen candidates

Malaria Journal

Research

John Sacci¹  Kalpana Gowda²  Martha Sedegah²  Thomas Richie²  Joao Aguiar³  Keith Limbach³  Esteban Abot³  Noelle Patterson³ 

[1] Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, USA;U.S. Military Malaria Vaccine Program, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, USA;U.S. Military Malaria Vaccine Program, Naval Medical Research Center, 503 Robert Grant Avenue, Silver Spring, MD, USA;Henry M. Jackson Foundation for the Advancement of Military Medicine, 1401 Rockville Pike (Suite 600), Rockville, MD, USA;

关键词: Malaria;    Malaria Vaccine;    Vaccine Vector;    Vaccinia Virus Vector;    Single Exon Gene;   

DOI  :  10.1186/1475-2875-10-65

 received in 2010-10-21, accepted in 2011-03-16,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundDespite years of effort, a licensed malaria vaccine is not yet available. One of the obstacles facing the development of a malaria vaccine is the extensive heterogeneity of many of the current malaria vaccine antigens. To counteract this antigenic diversity, an effective malaria vaccine may need to elicit an immune response against multiple malaria antigens, thereby limiting the negative impact of variability in any one antigen. Since most of the malaria vaccine antigens that have been evaluated in people have not elicited a protective immune response, there is a need to identify additional protective antigens. In this study, the efficacy of three pre-erythrocytic stage malaria antigens was evaluated in a Plasmodium yoelii/mouse protection model.MethodsMice were immunized with plasmid DNA and vaccinia virus vectors that expressed one, two or all three P. yoelii vaccine antigens. The immunized mice were challenged with 300 P. yoelii sporozoites and evaluated for subsequent infection.ResultsVaccines that expressed any one of the three antigens did not protect a high percentage of mice against a P. yoelii challenge. However, vaccines that expressed all three antigens protected a higher percentage of mice than a vaccine that expressed PyCSP, the most efficacious malaria vaccine antigen. Dissection of the multi-antigen vaccine indicated that protection was primarily associated with two of the three P. yoelii antigens. The protection elicited by a vaccine expressing these two antigens exceeded the sum of the protection elicited by the single antigen vaccines, suggesting a potential synergistic interaction.ConclusionsThis work identifies two promising malaria vaccine antigen candidates and suggests that a multi-antigen vaccine may be more efficacious than a single antigen vaccine.

【 授权许可】

CC BY   
© Limbach et al; licensee BioMed Central Ltd. 2011