Talking parasites? Communication between red blood cells infected with malaria

Scientists at the University of Melbourne have obtained the first evidence that malaria parasites can communicate within the human body. This important finding – outlined in the prestigious journal Cell – may provide a unique and novel niche for the development of antimalarial drugs and vaccines in the future.

The team, led by Professor Alan Cowman, found that communication between Plasmodium falciparum parasites (responsible for more than 75% of cases of malaria worldwide) can induce coordinated sexual maturation. This mass produces a form of the malaria parasite which can be taken up by female Anopheles mosquitoes (the “vector” for malaria parasites) to aid disease transmission and improve parasite survival.

The ‘messages’ are thought to be exchanged between parasites by exosome-like vesicles (minute, spherical “bags” of cell membrane) containing genes. The vesicles are shed by infected red blood cells, allowing parasites to transfer and receive information that may benefit the parasite population under different conditions. Professor Cowman’s team believe that the protein PfPTP2 plays an important role in this process, potentially by forcing red blood cells to take up circulating vesicles in the blood. Despite this, our knowledge of parasitic communication is highly limited, and the mechanism underlying the asexual to sexual transition of P. falciparum currently unknown.

With 700,000 people dying from malaria each year, improving our knowledge of how the malaria parasite survives, proliferates and undergoes interspecies transmission is critically important. With no effective malaria vaccines currently available, and increasing resistance to common anti-malarial drugs, the discovery of novel niches for drug and vaccine development is crucial for our fight against this pathogen.