How do cytotoxic T cells operate in the immune response?

Cytotoxic T cells, also known as CD8+ T cells, play a crucial role in the immune response by directly targeting and killing cells that are infected by viruses or have become cancerous. Once activated by recognizing a specific antigen presented on the surface of infected or malignant cells, these T cells release perforins and granzymes. Perforins form pores in the target cell's membrane, allowing granzymes to enter and trigger apoptosis, or programmed cell death, effectively eliminating the threat.

This mechanism of action is fundamental to controlling infections and preventing the spread of diseases like cancer. By directly attacking and destroying compromised cells, cytotoxic T cells help to maintain the integrity of the body’s tissues and prevent the progression of infections or tumor growth. This direct killing action distinguishes cytotoxic T cells from other immune cells that may have different roles, such as antibody production or the recruitment of other immune cells.