Researchers discover protein determining immune response to malaria
Researchers from Ireland and the UK have made an important breakthrough in the search for treatments for malaria and other infectious diseases. They have found why some people are more likely to contract and die from the disease than others. Their findings are published in the journal Nature Genetics. The researchers discovered an immune protein system protein called Mal which determines who contracts malaria and how well they deal with the infection. The protein is also shown to play a role against other diseases such as tuberculosis and pneumonia. In many ways, Mal acts like an alarm clock. When the body is attacked by a Malaria parasite, a set of sensors called toll-like receptors (TLRs) lock onto the parasite. The TLRs then send a message via Mal which effectively alerts the immune system to the presence of the parasite and mobilises it. 'We knew we had found an important part of the immune system, but this recent discovery clearly identifies Mal as being important for our immune system's capacity to fight infections such as malaria,' says Luke O'Neill who led the research at the Trinity College Dublin. But there are two types of Mal in humans. One type is deemed good because it enables the immune system to function as normal. However, a second variant results in Mal getting switched on too strongly. This causes the immune system to go into over-drive and heightens a person's chance of succumbing to the infection. 'Our work provides a striking example of how a key molecule in our immune system can be sacrificed to give some people better resistance to infectious disease,' explains Adrian Hill who led the research at the University of Oxford. The researchers studied over 6,000 patients with malaria, tuberculosis or pneumonia from Gambia, Vietnam, Turkey and the UK. They found that patients with the over-active Mal were twice as likely to contract the disease. In some populations there was a four-times greater risk of severe infection. The next steps will be to develop drugs that target the Mal pathway. 'We are very excited by the prospect that our work might be useful in the effort to come up with new strategies to prevent death during these infections,' says Professor O'Neill.
Countries
Ireland, United Kingdom