The study, led by Associate Professor Wai-Hon Tham and Ph.D. student Li-Jin Chen of the Australian Medical Research Institute, and Professor Christopher King of Case Western University, Ohio, United States, was published in the journal Nature Communications. The study helps scientists better understand how antibodies block the entry of the malaria parasite Plasmodium vivax into young red blood cells called reticulocytes.

How does malaria develop?

The malaria parasite is a complex, single-celled organism with a variety of proteins that help it enter, multiply, and spread throughout red blood cells. The most well-known malaria parasite in the world and the main cause of malaria in the vast majority of countries outside of Africa is Plasmodium vivax. On the surface of the parasite are the so-called key proteins that "open" the cells, allowing the parasite to enter. Until now, it was believed that it was impossible to resist this process. 

What does the new research tell us?

“We wanted to understand how these human antibodies when naturally infected, respond to the entry of the parasite into cells. By examining antibodies in people who have already had P. vivax infections, we have identified different ways human antibodies work against P. vivax.

Parasite proteins are too close to the membrane of the reticulocytes," said Wai-Hon Tham. In the future, researchers will carry out tests to find out whether the antibodies borrowed from those who recovered are capable of working in the body of healthy people.

If researchers can teach cells to recognize malaria and block it "on the fly," this will be a breakthrough in science and medicine.

Evidence base

Only 200 people took part in this study, but researchers are confident that the data obtained is enough to start the development of neutralizing antibodies that can fight malaria since 48 % of people developed immunity after the introduction of the drug based on foreign antibodies. For some, this was accompanied by symptoms of the disease in a mild form, while for others it did not cause any symptoms.

The goal of the researchers is to create a vaccine that is administered to humans once in a lifetime or on a regular basis, which guarantees the body's resistance to malaria.

If they succeed, we will be able to talk about malaria’s elimination as we talk about the elimination of smallpox and other diseases.

Sources: Li-Jin Chan et al. Naturally acquired blocking human monoclonal antibodies to Plasmodium vivax reticulocyte binding protein 2b, Nature Communications (2021). DOI: 10.1038/s41467-021-21811-2

08 July 2021