Cytotoxic T-cells, also known as CD8+ T-cells, are a type of white blood cell that play a crucial role in the immune system. They are responsible for identifying and destroying infected or cancerous cells in the body. These cells recognize specific antigens presented on the surface of infected cells, allowing them to target and eliminate threats effectively. Once activated, cytotoxic T-cells release proteins that induce cell death in their targets. This process helps to control infections and prevent the spread of diseases. Their activity is essential for maintaining the body's health and is a key focus in immunotherapy treatments for conditions like cancer.