What type of immunity involves T lymphocytes acting directly on infected or cancerous cells?

Cell-mediated immunity is characterized by the direct action of T lymphocytes, which are a type of white blood cell. These T cells play a critical role in the immune response by identifying and destroying infected or cancerous cells. Unlike humoral immunity, which relies on antibodies produced by B cells to neutralize pathogens, cell-mediated immunity activates and employs T cells to target and eliminate cells that display abnormal signals, such as those infected with viruses or transformed into cancerous cells.

This type of immunity is essential for clearing intracellular pathogens and is crucial in the body's defense against cancer. Additionally, cell-mediated immunity contributes to the overall adaptive immune response, which involves the specific recognition of antigens and the generation of a targeted defense. However, the distinction lies in the fact that cell-mediated immunity specifically highlights the function of T lymphocytes in directly engaging and eliminating affected cells, rather than relying on antibodies or passive transfer of immunity.