Malaria is a major global health burden, causing approximately 627, 000
deaths annually, especially in children under the age of five. There are
five Plasmodium species that infects humans, of which Plasmodium
falciparum (P.f.) and Plasmodium vivax(P.v.)are the two most prevalent. Currently,
no effective vaccine against malaria exists, hence the global effort aim to develop
a vaccine to prevent infection, limit disease and interrupt mosquito transmission for
all Plasmodium species.Glycosylphosphatidylinositol (GPI) is a potential target as
it isa conserved glycolipid anchor of many essentialparasite proteinsfound across
mostdifferentiated stages and Plasmodium species. Additionally, GPI is also a toxin
that causes immuno-pathological symptoms of malaria. Previously, we proved that
vaccination against GPI protects mice against severe malarial disease. This study
further investigates the potential of the synthetic anti-GPI vaccine in preventing
infection and blocking parasite transmission into the mosquito vector in a pre-clinical
rodent malaria model, P. berghei (P.b.). The vaccine showed significant efficacy in
reducing liver, blood stage infection and parasite transmission to the mosquito vector
independently. When mouse liver infection was left to progress through to blood
stage infection and parasite uptake by the mosquitoes,remarkable reduction in oocyst
numbers were observed in mosquitoes fed on vaccinated mice compared to those
fed on control mice. This suggests cumulative anti-GPI antibodies generated from
the vaccine have stronger parasite transmission blocking activity. This was further
validated by passively immunizing mice with anti-GPI antibodies prior to mosquito
infection and preliminary data showed similar reduction in oocyst burden in this group of mosquitoes.