Two studies from Indian and US researchers have identified malaria proteins that could boost global efforts to control the disease.
Indian researchers have identified a new protein that the mosquito Anopheles stephensi — the major vector of Plasmodium in urban India — releases from the salivary glands when it is infected by the malaria parasite.
The protein, defensin, is released as part of A. stephensi's immune response to Plasmodium infection, acting as an antimicrobial agent against the parasite and rendering the mosquito unable to transmit the parasite.
The study, published in the April issue of Acta Tropica, suggests that genetically manipulating the production of defensin in A. stephensi may make the mosquito resistant to the parasite — and unable to transmit it.
"Currently our group is looking to identify the potential molecules that are activated in mosquito tissues during Plasmodium infection and development," Rajnikant Dixit, a researcher at India's National Centre for Cell Science and author of the paper, told SciDev.Net.
In a separate study, published in the April issue of PLoS Pathogens, US researchers found a Plasmodium protein, called Heme Detoxification Protein (HDP), and say it represents a potential target for developing new antimalarial drugs.
Plasmodium infection causes destruction of red blood cells and releases heme, the non-protein component of haemoglobin, into the blood.
This heme is toxic to Plasmodium, but HDP enables the parasite to convert heme into a non-toxic substance — so preventing the protein's detoxification activity would hinder the parasite.
"We are going full-steam ahead to develop HDP as a drug target for malaria," Dharmendar Rathore, lead author of the study and an assistant professor at the Virginia Bioinformatic Institute, told SciDev.Net.
"Currently, we are looking for partners in the biopharmaceutical industry who have an interest in developing antimalarials and are willing to go hand-in-hand with us in this exciting journey."
Bikram Saha, assistant professor of Medicine at India-based Midnapore Medical College Hospital, cautions that it is important to see whether the studies yield any concrete malaria control methods.
"Basic studies are essential to further medical science, but to have an impact on clinical practice, they should be supported by further stages of research."
Acta Tropica 106, 75 (2008)
PLoS Pathogens doi 10.1371/journal.ppat.1000053 (2008)