IRP researchers discover novel class of anti-malaria antibodies

Friday, January 3, 2025

New antibodies could lead to next generation of interventions against malaria

A novel class of antibodies that binds to a previously untargeted portion of the malaria parasite could lead to new prevention methods, according to a study from researchers at the National Institutes of Health (NIH) published today in Science. The most potent of the new antibodies was found to provide protection against malaria parasites in an animal model. The researchers say antibodies in this class are particularly promising because they bind to regions of the malaria parasite not included in current malaria vaccines, providing a potential new tool for fighting this dangerous disease.

Malaria is a life-threatening disease caused by Plasmodium parasites, which are spread through the bites of infected mosquitoes. Although malaria is not common in the United States, its global impact is devastating, with 263 million cases and 597,000 deaths estimated by the World Health Organization in 2023. Of the five species of Plasmodium that cause malaria, Plasmodium falciparum is the most common in African countries where the burden of malaria is largest and where young children account for the majority of malaria deaths. Safe and effective countermeasures are critical for reducing the immense burden of this disease.

In recent years, new interventions have been developed against malaria, including vaccines that currently are being rolled out for young children in regions where the disease is prevalent. Anti-malarial monoclonal antibodies (mAbs) are another promising new tool that have been shown to be safe and efficacious against infection with P. falciparum in adults and children in early clinical trials. The anti-malarial mAbs evaluated in trials in malaria-endemic regions target the P. falciparum sporozoite — the life stage of the parasite that is transmitted from mosquitoes to people. By binding to and neutralizing the sporozoite, the mAbs prevent sporozoites from infecting the liver, where they otherwise develop into blood-stage parasites that infect blood cells and cause disease and death.

Colorized scanning electron micrograph of red blood cell infected with malaria parasites (orange/red/yellow). The small bumps on the infected cell show how the parasite remodels its host cell by forming protrusions called 'knobs' on the surface, enabling it to avoid destruction and cause inflammation. Uninfected cells (teal) have smoother surfaces.