New research shows bystander cell accumulation may play an active role in countering autoimmune diseases and curbing inflammation.
Autoimmune diseases are those in which the immune system attacks the body’s own cells leading to inflammation and damage of organs and tissues. Type 1 diabetes (T1D) is an example of an autoimmune disease caused by destruction of insulin-producing pancreatic cells (islet beta cells) by the immune system. Cytotoxic T cells that recognize islet beta cell antigens are the main immune cells responsible for the changes seen in T1D, but cytotoxic T cells that do not recognize these antigens are also found to infiltrate the pancreatic tissue. These cells have been designated bystander cells and have been thought to passively contribute to autoimmune-related tissue damage.