Cells could hold key to HIV fight NEW research has revealed that people with a high number of a receptors known as HLA-C within their body's cells can naturally inhibit HIV. However, the same people may also be at higher risk of autoimmune diseases such as Crohns disease, the major international research study has discovered. Researchers from Western Australia's Murdoch University have helped discover the amount of the HLA-C receptor could play a crucial role in the immune defence against viruses, including HIV. The research, led by Dr Mary Carrington of the Frederick National Laboratory for Cancer Research in Maryland USA, will be published in Science magazine on Friday. Dr Mina John of Murdoch University's Institute for Immunology and Infectious Diseases (IIID) says the discovery that people with more abundant HLA-C receptors are more resistant to HIV could help shape future treatments. "We've known that HLA-C plays a role in the immune defence against viruses, including HIV, however, this large-scale study confirms that it is the quantity of HLA-C on cells, or the expression level, that is the crucial factor in protection," Dr John said. HLA-C are a class of receptors present on the surface membranes of almost all human cells and tissues, and are a vital part of the recognition system against infections. When a virus invades a cell, HLA-C receptors bind small pieces of the virus and present them to surrounding cells to engage the immune system, which then sends killer cells to destroy the infected cells. In a less positive breakthrough, the study also revealed that the risk of Crohns disease was increased in those with a high expression level of HLA-C receptors. "This shows that a more vigorous immune response helps fight infections, but this can be harmful if the immune response is directed against the body's own tissues, as in Crohns disease and other autoimmune diseases," Dr John said.