Which of the following best defines the role of cytotoxic T cells?

Cytotoxic T cells play a vital role in the immune response by specifically targeting and eliminating infected cells, often those infected by viruses or other intracellular pathogens. They recognize infected cells through specific antigens presented on the surface of these cells, which are identified by the T cell receptors (TCR). Upon recognition, cytotoxic T cells induce apoptosis (programmed cell death) in the infected cells, effectively reducing the spread of the infection and aiding in the overall coordination of the immune response.

This direct action is crucial for controlling and clearing infections, particularly since some pathogens can hide within host cells. Their ability to selectively destroy these compromised cells helps to protect the integrity of healthy tissues and contributes significantly to cell-mediated immunity. Understanding this function of cytotoxic T cells is fundamental when studying how the immune system responds to internal threats such as viral infections.