Describe the process whereby Natural killer cells kill other cells and the role of macrophages in the process.

Question: Describe the process whereby Natural killer cells kill other cells and the role of macrophages in the process.

Natural killer cells, or NK cells, are a type of lymphocyte that can kill infected or abnormal cells. They do this by recognizing stress signals on the cell surface, such as molecules that are upregulated by viral infection or cancer. NK cells also have receptors for antibodies, which allow them to bind to cells that are coated with antibodies and kill them by a process called antibody-dependent cellular cytotoxicity (ADCC). Macrophages are another type of immune cell that can engulf and digest foreign particles or microbes. They can also activate NK cells by releasing cytokines, which are chemical messengers that stimulate immune responses. NK cells and macrophages work together to eliminate threats and maintain homeostasis in the body.