A groundbreaking approach to preventing the spread of malaria – a disease that poses a significant threat to millions worldwide – could soon become a reality, thanks to the pioneering work of scientists at The Walter and Eliza Hall Institute of Medical Research (WEHI) in Australia. While vaccines for malaria do exist, the WEHI team took a novel approach by targeting the root cause: the protein complex responsible for the reproduction of the Plasmodium falciparum parasite inside mosquitoes.
By leveraging mRNA vaccine technology similar to that used for some COVID-19 vaccines, the researchers developed a transmission-blocking vaccine that showed remarkable results in preclinical studies – a staggering 99.7% drop in the rate of transmission. This breakthrough has significant implications for the fight against malaria, which affects nearly 300 million people annually and claims 600,000 lives each year.
The WEHI team employed a structural biology approach to visualize the protein complex responsible for parasite reproduction, revealing a crucial connection between two proteins – Pfs230 and Pfs48/45. Lead researcher Dr. Melanie Dietrich explained: "Using cryo-electron microscopy, we were able to visualize the full fertilization complex directly from the parasite, not a lab-made version." This groundbreaking discovery unlocked a powerful new vaccine target.
The researchers then created an mRNA vaccine that targeted the contact points responsible for binding these two proteins. The result was high levels of antibodies that caused the parasite's fertilization to fail inside mosquitoes and blocked transmission.
While this vaccine has yet to undergo clinical trials, it marks a crucial step forward in the battle against malaria – a disease already being tackled by formidable forces aiming to eliminate it. In India, for example, a new vaccine designed to prevent parasitic infection is showing promise in lab studies but still has several years of development ahead.
In related news, Novartis recently approved a treatment specifically for young babies and small children under 10 lb (4.5 kg), marking the first malaria treatment developed for this age group. This milestone underscores the complexity of combating malaria, which requires a multi-stage strategy that targets the parasite in both mosquitoes and human hosts.
The WEHI scientists envision their transmission-blocking vaccine as part of a holistic approach to combat malaria – one that would work in tandem with other vaccines targeting blood or liver stages in people. The team published its findings on structural biology in the journal Science last week, paving the way for further research and development.
Source: The Walter and Eliza Hall Institute of Medical Research