Macrophages and other immune effector cells

Macrophages and other immune effector cells, such as T cells, B cells, and Natural Killer (NK) cells, are the primary cellular components of the immune system responsible for host defense and tissue homeostasis. Macrophages are versatile myeloid cells that perform phagocytosis, produce cytokines, and present antigens to bridge innate and adaptive immunity (Source: StatPearls, PMID: 32119442). Other effector cells provide specialized functions, including antibody production by B cells and direct cytotoxicity by T and NK cells. In pathological states like cancer, these cells can be subverted to support tumor growth, such as tumor-associated macrophages (TAMs) which promote an immunosuppressive microenvironment (Source: Journal of Hematology & Oncology, doi:10.1186/s13045-019-0760-3). Conversely, in autoimmune diseases, these cells may mistakenly attack healthy tissues, leading to chronic inflammation (Source: Nature Reviews Immunology, doi:10.1038/s41577-020-0306-5). Modern pharmacology targets these cells not as a whole, but through specific molecular checkpoints, receptors, or secreted factors to treat a wide range of immunological and oncological conditions.

Other names

Immune cellsLeukocytesWhite blood cellsMyeloid and lymphoid effector cellsPhagocytes

Drugs typically target specific molecular markers (e.g., CD20, PD-1) or signaling pathways (e.g., JAK/STAT) within these cell populations to modulate immune activity, deplete specific cell subsets, or inhibit inflammatory mediators.