A prime-boost immunization regimen based on a simian adenovirus 36 vectored multi-stage malaria vaccine induces protective immunity in mice.

A prime-boost immunization regimen based on a simian adenovirus 36 vectored multi-stage malaria vaccine induces protective immunity in mice. Vaccine. 2017 May 05;: Authors: Fonseca JA, McCaffery JN, Kashentseva E, Singh B, Dmitriev IP, Curiel DT, Moreno A Abstract Malaria remains a considerable burden on public health. In 2015, the WHO estimates there were 212 million malaria cases causing nearly 429,000 deaths globally. A highly effective malaria vaccine is needed to reduce the burden of this disease. We have developed an experimental vaccine candidate (PyCMP) based on pre-erythrocytic (CSP) and erythrocytic (MSP1) stage antigens derived from the rodent malaria parasite P. yoelii. Our protein-based vaccine construct induces protective antibodies and CD4(+) T cell responses. Based on evidence that viral vectors increase CD8(+) T cell-mediated immunity, we also have tested heterologous prime-boost immunization regimens that included human adenovirus serotype 5 vector (Ad5), obtaining protective CD8(+) T cell responses. While Ad5 is commonly used for vaccine studies, the high prevalence of pre-existing immunity to Ad5 severely compromises its utility. Here, we report the use of the novel simian adenovirus 36 (SAd36) as a candidate for a vectored malaria vaccine since this virus is not known to infect humans, and it is not neutralized by anti-Ad5 antibodies. Our study shows that the recombinant SAd36PyCMP can enhance specific CD8(+) T c...
Source: Vaccine - Category: Allergy & Immunology Authors: Tags: Vaccine Source Type: research