What does cell-mediated immunity involve?

Cell-mediated immunity is primarily characterized by the role of T-cells in the immune response. This form of immunity involves T-cells directly attacking and destroying infected cells or cancerous cells that present antigens on their surfaces. Unlike humoral immunity, which relies on B-cells producing antibodies to neutralize pathogens, cell-mediated immunity focuses on the actions of T-cells, particularly cytotoxic T-cells that recognize specific antigens and initiate the destruction of target cells.

The involvement of T-cells means that cell-mediated immunity is crucial for combating intracellular pathogens, such as viruses and some bacteria, that can reside within cells. This direct attack mechanism is vital for maintaining the body's defense against infections that evade antibody-mediated responses.

Other aspects of the immune response, such as the release of cytokines or the production of memory cells, play supportive roles in the overall immune process but do not define cell-mediated immunity specifically. Cytokines are signaling molecules that help regulate the immune response, and memory cells are important for long-term immunity but are part of both the cell-mediated and humoral responses. Thus, the correct understanding of cell-mediated immunity centers on the direct action of T-cells against antigens.