HQ Team
September 28, 2023: Using structural and mechanistic information of two parasitic proteins, scientists have built a new component for a vaccine that may induce an immune response to malaria.
The new protein, called SBD1 (structure-based design 1), helps form antibodies capable of blocking the crucial attachment of two malarial parasites responsible for piercing into a cell’s interior.
The earlier vaccine could not protect against other parasite strains and had limited usefulness in malaria-endemic countries, according to a study by the US-based National Institute of Allergy and Infectious Diseases.
Existing experimental malaria vaccines are a mixture of the two parasitic proteins — AMA1 and RON2L. These trigger more strain-transcending antibodies and they are difficult to make.
Simple mixtures of AMA1 and RON2L in vaccines do not form the kind of stable protein complex seen in nature, according to the study.
Easy to manufacture
When tested in rats, the new SBD1 immunogen vaccine performed better than any other vaccine, said Niraj H. Tolia, who led the research team.
The SBD1 immunogen is highly stable once injected, is easy to manufacture in large quantities and consistently takes the desired, immune-stimulating shape, said Mr Tolia.
In rats, the SBD1 vaccine generated significantly “more potent strain-transcending antibodies than either AMA1 alone or an AMA1-RON2L complex vaccine,” he said.
The SBD1 could be a candidate for further studies in animals and ultimately in human trials, he said. It may be applicable to other diseases such as toxoplasmosis and babesiosis.
Babesia species has the protozoan parasites that cause malaria, and toxoplasmosis.
Toxoplasmosis can cause severe lung or brain disease for a person with weakened immunity
