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Scientists coordinated by Imperial College London have developed a study that shows how the malaria parasite penetrates the red blood cell by interacting with the receptors, the "glycophorins", of the membrane that separates the cell from the outside world. Parasites that leave the liver have molecular "engines" that aid in the penetration of the red blood cell. However, the study shows that they can still alter cell properties to get input. This allows them to make the cell wall more flexible.

The researchers showed how the parasite protein responsible for cell invasion, the already known EBA175, affects the physical properties of the membrane, weakening the defense of the cell directly. However, the research revealed that differences in membrane stiffness may have an influence on parasite invasiveness. This means that cholesterol can have a protective effect against malaria infection.

According to the results, red blood cells with higher cholesterol levels could be more resistant to invasion and, consequently, to parasite infection. "We found that red blood cell entry is not only due to the ability of the parasite itself, but that changes initiated by parasites in red blood cells appear to contribute to the invasion process," says Marion Koch, the study's first author.

Source: PNAS.

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