Slow progress is being made in the development of means to adjust the operation and configuration of the immune system, especially when it comes to damping inflammation. Present approaches used in the clinic are blunt, suppressing immune activity as a whole, or at least large swathes of it, and have significant side-effects. More sophisticated ways to adjust immune cell behavior may have applications in reducing some of the consequences of the disarray of the immune system that occurs with age. In particular, if the chronic inflammation and overactivity of the aged immune system could be reduced, some benefits might be realized. In the longer term, however, the real relevance of this sort of work is as a stepping stone towards a greater capacity to arbitrarily adjust the immune system in situ, changing or destroying very specific subpopulations of immune cells in order to achieve desired effects. It is possible that this could lead to the prevention of misconfiguration and change in relative numbers of immune cells that occurs with age.
Scientists have revealed, for the first time, a method to reprogram specific T cells. More precisely, they discovered how to turn pro-inflammatory cells that boost the immune system into anti-inflammatory cells that suppress it, and vice versa. The researchers studied two types of cells called effector T cells, which activate the immune system to defend our body against different pathogens, and regulatory T cells, which help control the immune system and prevent it from attacking healthy parts of its environment.
By drawing on their expertise in drug discovery, the team identified a small-molecule drug that can successfully reprogram effector T cells into regulatory T cells. Their study describes in detail a metabolic mechanism that helps convert one cell type into another. This new approach to reprogram T cells could have several medical applications. For instance, in autoimmune disease, effector T cells are overly activated and cause damage to body. Converting these cells into regulatory T cells could help reduce the hyperactivity and return balance to the immune system, thus treating the root of the disease. In addition, the study could improve therapies using stem cells. At least in theory, producing regulatory T cells could promote immune tolerance and prevent the body from rejecting newly-transplanted cells.
“Our work could also contribute to ongoing efforts in immunotherapy for the treatment of cancer. This type of therapy doesn’t target the cancer directly, but rather works on activating the immune system so it can recognize cancer cells and attack them.” Many cancers take control of regulatory T cells to suppress the immune system, creating an environment where tumors can grow without being detected. In such cases, the team’s findings could be used to transform regulatory T cells into effector T cells to strengthen the immune system so it can better recognize and destroy cancer cells.