Sydney: In a finding that could lead to new drugs to treat cancer and autoimmune diseases, researchers, including one of Indian-origin, have discovered a new way of triggering cell death. Programmed cell death, also called apoptosis, is a natural process that removes unwanted cells from the body. Failure of apoptosis can allow cancer cells to grow unchecked or immune cells to inappropriately attack the body. The protein known as Bak is central to apoptosis. In healthy cells Bak sits in an inert state but when a cell receives a signal to die, Bak transforms into a killer protein that destroys the cell. In this study, researcher Sweta Iyer from the Walter and Eliza Hall Institute of Medical Research, Victoria, and colleagues discovered a novel way of directly activating Bak to trigger cell death. The researchers discovered that an antibody they had produced to study Bak actually bound to the Bak protein and triggered its activation. "We were excited when we realised we had found an entirely new way of activating Bak," said Ruth Kluck who is also from Walter and Eliza Hall Institute of Medical Research in Australia. The researchers hope to use this discovery to develop drugs that promote cell death. "There is great interest in developing drugs that trigger Bak activation to treat diseases such as cancer where apoptosis has gone awry," she said. "This discovery gives us a new starting point for developing therapies that directly activate Bak and cause cell death," Kluck pointed out. The researchers used information about Bak's three-dimensional structure to find out precisely how the antibody activated Bak. The study was published in the journal Nature Communications. "The advantage of our antibody is that it can't be 'mopped up' and neutralised by pro-survival proteins in the cell, potentially reducing the chance of drug resistance occurring," Kluck said.