The huge difference between a chronic and potentially fatal medical condition called
AIDS and HIV infection is owing to the huge die off of CD4 T cells in the immune system. The researchers have found that the virus destroys only a tiny portion of such cells leading to a question – What makes the other cells to vanish?
Latest research reveals that the human body can kill its own cells through an unknown process and a safe drug can disturb this self destruction cycle, thereby offering a way to treat the condition of AIDS. This process of destruction has caught the scientists by surprise. Warner Greene, Director, Virology and Immunology, Gladstone Institute, said that they thought HIV could infect the cell , holds a production factory of virus and as a result the cell dies owing to the action of virus. However he added that there were not enough virus factories to offer an explanation behind such drastic cell losses.
Greene also expressed his suspicion that researchers in the past had failed to detect this process as they were looking elsewhere. Instead of making a study in the CD4 T cells present in the blood, his team examined the tonsil tissues and spleen where tissues are in resting stage. The HIV while entering this resting cell transcribes the genes to DNA but the replication process stops as the cell machinery is not present.
However, Greene’s team made a shocking discovery that instead of putting an end there, the cells were able to detect the presence of DNA in cytoplasm and launched an immune response against this. This in turn caused the death of the cells. This was due to a self destructing protocol known as pyroptosis, which offers a fiery cell death when compared to apoptosis where cell experience a quiet death, says Greene. This might be the cause of high inflammation levels associated with HIV as the cell leaves chemicals that can cause inflammation while they die.
Greene’s team performed an experiment which showed that the cell death could be stopped fully when an essential component of pyroptosis was blocked. This action caused the overall cell death and this was found in the fresh lymph node from a patient that showed the death of resting cells and the ones present in the center of the node.
Greene estimates that about 95% of the cell death owing to HIV infection are due to pyroptosis and this study triggers hope for a latest treatment as it has the ability to treat HIV from advancing into AIDS. This study, according to Greene, would help reduce the risk among the patients with AIDS as it would prevent them being prone to age related issues such as heart issues or kidney damage.
Greene and his team have published two papers Monday in Nature and Science.