Drug protects against malaria infection in mice

◗ Malaria is the second leading cause of infectious disease worldwide, and took more than a half million lives in 2013. To date, no completely effective vaccine exists.

Washington, July 16: Scientists have developed a drug that protects against malaria infection in mice, paving the way for a human vaccine that works by targeting the specific protein that the parasites use to evade the immune system.

Malaria is the second leading cause of infectious disease worldwide, and took more than a half million lives in 2013, according to the study published in the journal Nature Communications.

To date, no completely effective vaccine exists, and infected individuals only develop partial immunity against disease symptoms.

In a prior study, researchers described a unique protein produced by malaria parasites, Plasmodium macrophage migration inhibitory factor ( PMIF), which suppresses memory T cells, the infection- fighting cells that respond to threats and protect the body against reinfection.

In the new study, researchers at Yale University in the US collaborated with Novartis Vaccines, to test an RNA based vaccine designed to target PMIF.

First, using a strain of the malaria parasite with PMIF genetically deleted, they observed that mice infected with that strain developed memory T cells and showed stronger anti parasite immunity.

Next, the research team used two mouse models of malaria to test the effectiveness of a vaccine using PMIF.

The next step for the research team is to develop a vaccine for those who have never had malaria.

One model had earlystage liver infection from parasites carried by mosquitos, and the other, a severe, late- stage blood infection.

In both models, the vaccine protected against reinfection. As a final test, the researchers transferred memory T cells from the immunised mice to ‘ naive’ mice never exposed to malaria.