New Approach Toward A Broad Spectrum Malaria Vaccine

New Approach Toward A Broad Spectrum Malaria Vaccine
In a recent breakthrough to combat malaria, scientists have identified a malarial parasite protein that can be used to develop antibodies when displayed on novel nanoparticles. This approach has the potential to prevent the parasite from multiplying in the human host and also inhibits transmission through mosquitoes. The finding points towards developing a powerful malaria vaccine in the hope of eradicating this debilitating and often fatal disease.
Malaria takes a heavy toll on human lives. About half a million people die every year and several hundred million suffer from this disease across the globe. To add to the disease burden, the malaria parasite is increasingly becoming resistant to commonly used anti-malarial drugs. Development of an anti-malarial vaccine is an integral part of an effort to counter the socio-economic burden of malaria.
Researchers at Tata Institute of Fundamental Research (TIFR), India, have now identified a five amino acid segment of a Plasmodium parasite protein that is normally involved in producing energy from glucose. Research has earlier shown that this protein, enolase, is a protective antigen and has several other functions that are essential for parasite growth and multiplication.
Taking this a step further, in a recently published paper in the Malaria Journal, they have shown that a small part of this protein, that is unique to parasite enolase and is absent in human enolases, has protective antigenic properties.
New Approach Toward A Broad Spectrum Malaria Vaccine
Pentapeptide insert from Plasmodium spp enolase is displayed
on Archaeal gas vesicle nanoparticles. Recombinant particles
were used to immunize mice. After two boosters, immunized
mice were challenged with a lethal mouse malarial parasite and
compared with other mice that were immunized with native gas
vesicles. Comparison shows prolonged survival for
pentapeptide immunized mice. (Credit: Sneha Dutta)
The work was carried out in collaboration with researchers at the University of Maryland School of Medicine, USA, who has developed Archaeal gas vesicle nanoparticles (GVNPs). The small unique segment of enolase was genetically fused to a nanoparticle protein and this conjugated system was used to vaccinate mice. Interestingly, a subsequent challenge with a lethal strain of mouse malaria parasite in these vaccinated animals showed considerable protection against malaria.
This study is a significant advance in the field, since most other vaccine candidate molecules tested so far confer protection against only a single species of parasite, due to the species and strain specific nature of these molecules. "The small segment of five amino acids that forms a protective epitope is present in all human malaria causing species of Plasmodium and hence, antibodies directed against it are likely to protect against all species of the parasite", the researchers said.
Efforts are now focused at developing this into an effective vaccine against malaria.
Based on material originally posted by Tata Institute of Fundamental Research.