Which mechanism of immunity involves mast cells, macrophages, and white blood cells?

Cell-mediated immunity is primarily characterized by the involvement of various immune cells, such as mast cells, macrophages, and white blood cells, specifically T lymphocytes and certain types of innate immune cells. This branch of the immune system is crucial for controlling infections, particularly those caused by intracellular pathogens like viruses and some bacteria.

Mast cells play a role in allergic responses and can also respond to infections by coordinating the immune response. Macrophages are essential for phagocytosing pathogens and presenting antigens to T cells, thereby activating them and facilitating a targeted immune response. White blood cells, including cytotoxic T cells, directly destroy infected cells or help orchestrate the immune response.

The correct mechanism, therefore, reflects the active role of these various cell types in recognizing and responding to pathogens through complex cellular interactions, rather than relying solely on antibodies, which is characteristic of humoral immunity.