Dataset Information

Comparative assessment of vaccine vectors encoding ten malaria antigens identifies two protective liver-stage candidates.

ABSTRACT: The development of an efficacious Plasmodium falciparum malaria vaccine remains a top priority for global health. Vaccination with irradiated sporozoites is able to provide complete sterile protection through the action of CD8(+) T cells at the liver-stage of infection. However, this method is currently unsuitable for large-scale deployment and focus has instead turned to the development of sub-unit vaccines. Sub-unit vaccine efforts have traditionally focused on two well-known pre-erythrocytic antigens, CSP and TRAP, yet thousands of genes are expressed in the liver-stage. We sought to assess the ability of eight alternative P. falciparum pre-erythrocytic antigens to induce a high proportion of CD8(+) T cells. We show that all antigens, when expressed individually in the non-replicating viral vectors ChAd63 and MVA, are capable of inducing an immune response in mice. Furthermore, we also developed chimeric P. berghei parasites expressing the cognate P. falciparum antigen to enable assessment of efficacy in mice. Our preliminary results indicate that vectors encoding either PfLSA1 or PfLSAP2 are capable of inducing sterile protection dependent on the presence of CD8(+) T cells. This work has identified two promising P. falciparum liver-stage candidate antigens that will now undergo further testing in humans.

SUBMITTER: Longley RJ

PROVIDER: S-EPMC4490344 | biostudies-literature | 2015 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Comparative assessment of vaccine vectors encoding ten malaria antigens identifies two protective liver-stage candidates.

Longley Rhea J RJ Salman Ahmed M AM Cottingham Matthew G MG Ewer Katie K Janse Chris J CJ Khan Shahid M SM Spencer Alexandra J AJ Hill Adrian V S AVS

Scientific reports 20150703

The development of an efficacious Plasmodium falciparum malaria vaccine remains a top priority for global health. Vaccination with irradiated sporozoites is able to provide complete sterile protection through the action of CD8(+) T cells at the liver-stage of infection. However, this method is currently unsuitable for large-scale deployment and focus has instead turned to the development of sub-unit vaccines. Sub-unit vaccine efforts have traditionally focused on two well-known pre-erythrocytic ...[more]

PMID: 26139288

Similar Datasets

Project description:The extensive diversity of Plasmodium falciparum antigens is a major obstacle to a broadly effective malaria vaccine but population genetics has rarely been used to guide vaccine design. We have completed a meta-population genetic analysis of the genes encoding ten leading P. falciparum vaccine antigens, including the pre-erythrocytic antigens csp, trap, lsa1 and glurp; the merozoite antigens eba175, ama1, msp's 1, 3 and 4, and the gametocyte antigen pfs48/45. A total of 4553 antigen sequences were assembled from published data and we estimated the range and distribution of diversity worldwide using traditional population genetics, Bayesian clustering and network analysis. Although a large number of distinct haplotypes were identified for each antigen, they were organized into a limited number of discrete subgroups. While the non-merozoite antigens showed geographically variable levels of diversity and geographic restriction of specific subgroups, the merozoite antigens had high levels of diversity globally, and a worldwide distribution of each subgroup. This shows that the diversity of the non-merozoite antigens is organized by physical or other location-specific barriers to gene flow and that of merozoite antigens by features intrinsic to all populations, one important possibility being the immune response of the human host. We also show that current malaria vaccine formulations are based upon low prevalence haplotypes from a single subgroup and thus may represent only a small proportion of the global parasite population. This study demonstrates significant contrasts in the population structure of P. falciparum vaccine candidates that are consistent with the merozoite antigens being under stronger balancing selection than non-merozoite antigens and suggesting that unique approaches to vaccine design will be required. The results of this study also provide a realistic framework for the diversity of these antigens to be incorporated into the design of next-generation malaria vaccines.

Dataset Information

Comparative assessment of vaccine vectors encoding ten malaria antigens identifies two protective liver-stage candidates.

Publications

Comparative assessment of vaccine vectors encoding ten malaria antigens identifies two protective liver-stage candidates.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets