Geelong researcher leads charge for malaria vaccine

A vaccine against malaria might soon be possible, a Geelong-based researcher has suggested.

Associate Professor Alyssa Barry, who’s based at Deakin University’s Waurn Ponds campus, said a team of researchers have made a “major step” towards developing a vaccination capable of fighting off the most severe forms of malaria.

This was achieved by using antibody measurements from hundreds of different variants of proteins from children in Papua New Guinea who had contracted the disease to pinpoint which antibodies were most effective in stopping malaria in its tracks.

Associate Professor Barry said malaria parasites grow within red blood cells where they insert proteins (known as PfEMP1) into the surface.

“As part of their survival strategy within the human host, malaria parasites use PfEMP1 to stick to the walls of blood vessels, and this can cause blockages to blood flow and inflammation, leading to severe disease.

“Malaria parasites change these proteins to escape from developing immune responses, and every strain has a different set of proteins, making the identification of vaccine targets like finding a needle in a haystack.”

According to the latest figures from the World Health Organization, there were 219 million cases of malaria worldwide in 2017, leading to an estimated 435,000 deaths.

The team – which comprised of Associate Professor Barry, the Walter and Eliza Hall Institute of Medical Research (WEHI), James Cook University and malaria experts from Papua New Guinea – are the first researchers to demonstrate that a vaccination could be possible based on PfEMP1.

“For years researchers have thought that developing a malaria vaccine based on PfEMP1 would be virtually impossible because the proteins are just so diverse,” Associate Professor Barry said.

“It’s similar to the flu vaccine, where you have to keep adjusting and updating it as the virus strains evolve from year to year. Malaria is even more diverse than influenza – one village in a country such as PNG could contain thousands of possible PfEMP1 variants.

“But in malaria-endemic areas, children who are repeatedly infected develop immunity to severe malaria by the time they’re about two years old, so we know antimalarial immunity is possible, and it can develop after exposure to only a few strains.

“It’s been a long road, and has involved a large team, but it’s a major step forward, and this provides hope that creating a vaccine might be possible.”

The full research findings have been published in the Cell Host and Microbe scientific journal.