How Malaria Parasites Invade Human Cells; Scientists Discovered Vaccine

June 28, 2018  Source: ScienceDaily 194

Scientists from the Melbourne Walter and Eliza Hall Institute and the Howard Hughes Medical Institute (US) have discovered a new vaccine for malaria, revealing an 'atomic-scale' blueprint of how the parasite seize human cells using a new technology called CRYO-EM (cryo-electron microscopy).

Associate professor Wai-Hong Tham and Dr. Jakub Gruszczyk from the Walter and Eliza Hall Institute in Melbourne's partnering along with Dr. Rick Huang and Dr. Zhiheng Yu from the Howard Hughes Medical Institute (US) initiated to develop a vaccine for malaria. With the help of the Nobel Prize-winning technology cryo-EM, the scientist traced earlier unseen "first contact" between the Plasmodium vivax malaria parasites and young red blood cells that invade and initiate the parasites' spread throughout the body. The researcher solved the enigma of the molecular machinery the parasite used to hold on to red blood cells.

To gain access to red blood cell, Plasmodium vivax parasites use the human transferrin receptor according to the scientists. With the help of cryo-EM, the team was able to control previous technical challenges to envision the interaction at an atomic level.

Professor Wai-Hong Tham said "We've now mapped, down to the atomic level, exactly how the parasite interacts with the human transferrin receptor. This is critical for taking our original finding to the next stage -- developing potential new antimalarial drugs and vaccines. Cryo-EM is really opening doors for researchers to visualize structures that were previously too large and complex to 'solve' before."

 She also added that with the guidance of the 3D map the team was able to tease out the precise details of the parasite-host interaction, identifying its most vulnerable spots. "It's basically a design challenge. P. vivax parasites are incredibly diverse -- which is challenging for vaccine development. We have now identified the molecular machinery that would be the best target for an antimalarial vaccine effective against the widest range of P. vivax parasites. With this unprecedented level of detail, we can now begin to design new therapies that specifically target and disrupt the parasite's invasion machinery, preventing malaria parasites from hijacking human red blood cells to spread through the blood and, ultimately, be transmitted to others."

By Ddu