Scientists find new way to treat malaria

An Indian-origin scientist has found how a malaria strain, common in India and Southeast Asia, attacks human red blood cells, a discovery that may aid vaccine development for the disease.
The malaria type attacks human red blood cells by clamping down on the cells with a pair of proteins, new research at Washington University School of Medicine in St Louis has found.
The study provides details that will help scientists design better vaccines and drug treatments for the strain, Plasmodium vivax, researchers said.
"More people live at risk of infection by this strain of malaria than any other," said senior author Niraj Tolia, assistant professor of molecular microbiology and of Biochemistry and molecular biophysics.

"We now are using what we have learned to create vaccines tailored to stop the infectious process by preventing the parasite from attaching to red blood cells," Tolia said.
P vivax can hide in the liver, re-emerging years later to trigger new infections, and is harder to prevent, diagnose and treat, researchers said.

Earlier studies had suggested that one P vivax protein binds to one protein on the surface of red blood cells.
Tolia's new study reveals that the binding is a two-step process that involves two copies of a parasite protein coming together like tongs around two copies of a host protein.

"It's a very intricate and chemically strong interaction that was not easily understood before," Tolia said.
"We have had hints that other forms of malaria, including the African strain, may be binding in a similar fashion to host cells, but this is one of the first definitive proofs of this kind of attack," said Tolia.
Tolia suspects blocking any of the proteins with drugs or vaccines will stop the infectious process.
"For example, some people have a mutation that eliminates the protein on red blood cell surfaces that P vivax binds to, and they tend to be resistant to the parasite," he said.

The study was published in the journal PLOS Pathogens.