Researchers may be one step closer to creating a malaria vaccine. According to a study published in Nature Communications, scientists at Yale have developed a vaccine that protects against malaria infection in mouse models by targeting a protein malaria uses to invade cells.
In a prior study, senior author Richard Bucala, M.D. identified a unique protein produced by malaria parasites, called Plasmodium macrophage migration inhibitory factory (PMIF), that acts to suppress memory T cells. Based on these findings, the team developed an RNA-based vaccine to target PMIF.
First, they infected mice with a malaria strain with PMIF genetically deleted. Mice infected with this strain developed memory T cells following infection and showed stronger anti-parasite immunity. Next, they tested their PMIF-targeting vaccine on mice with early-stage liver infection from mosquito-borne infection as well as those with a late-liver infection. In both cases, the vaccine protected against reinfection. Finally, the researchers transferred memory T cells from immunized mice to those who had never experience infection, observing that these mice were also protected.
"If you vaccinate with this specific protein used by the malaria parasite to evade an immune response, you can elicit protection against re-infection," said Bucala. The next step is for the team to develop vaccines for never-before-infected individuals, particularly young children.
Because PMIF has been conserved by evolution, the researchers predict it would be highly unlikely for the parasite to develop resistance to such a vaccine. Other diseases—such as Leishmaniasis, Hookworm, and Filariais—produce similar proteins, indicating these findings could be applied to other types of disease research.