Natural killer (NK) cells are a type of white blood cell that plays a crucial role in the immune system. They are part of the body's first line of defense against infections and tumors. NK cells are named for their ability to kill certain types of cells, such as virus-infected cells and cancer cells, without prior sensitization to them.
Natural killer cells are important for maintaining health as they help to identify and destroy cells that may be harmful to the body. By targeting infected or cancerous cells, NK cells contribute to the body's ability to prevent the spread of diseases. Their activity is essential for immune surveillance, which is the process by which the immune system monitors for abnormalities.
In the body, natural killer cells function by recognizing stressed or infected cells and releasing substances that can lead to cell death. They also produce proteins that help regulate other immune cells, enhancing the overall immune response. This makes them vital for both innate and adaptive immunity, as they can quickly respond to threats while also helping to shape the longer-term immune response.
In addition to their role in fighting infections and cancer, natural killer cells can be influenced by various factors, including medications like rapamycin, which can suppress their activity. Understanding NK cells is important for developing new therapies in immunology and cancer treatment.