Antibody-dependent cell-mediated cytotoxicity (ADCC) is a mechanism by which the immune system targets and eliminates harmful cells, such as virus-infected or cancerous cells. ADCC is carried out by specialized immune cells, including natural killer (NK) cells and certain subsets of T cells.
In ADCC, antibodies bind to specific proteins on the surface of target cells, marking them for destruction. The Fc portion of the antibody then interacts with Fc receptors on the surface of NK cells or other immune cells, activating them and triggering the release of cytotoxic granules. These granules contain perforin and granzymes, which enter the target cell and cause it to undergo apoptosis (programmed cell death).
ADCC is an important mechanism of action for certain types of immunotherapy, particularly monoclonal antibodies. These antibodies are designed to target specific proteins on the surface of cancer cells, for example, and trigger ADCC by engaging immune cells to destroy the cancer cells. The effectiveness of ADCC in eliminating target cells can be influenced by factors such as the affinity of the antibody for its target and the activation state of the immune cells involved.