Activated neutrophils and monocytes

Activated neutrophils and monocytes are the primary cellular effectors of the innate immune system, serving as the first line of defense against pathogens and tissue damage (StatPearls, 2023). Neutrophils are characterized by their ability to perform phagocytosis, release antimicrobial granules, and generate neutrophil extracellular traps (NETs), while monocytes circulate in the blood and migrate into tissues to differentiate into macrophages or dendritic cells (Nature Reviews Immunology, 2018). In pathological states, the excessive or chronic activation of these cells contributes to the progression of inflammatory diseases, such as rheumatoid arthritis, vasculitis, and acute respiratory distress syndrome (ARDS), by releasing pro-inflammatory cytokines and reactive oxygen species (Journal of Leukocyte Biology, 2020). Therapeutic interventions targeting these cells often involve broad-spectrum immunosuppressants like glucocorticoids or targeted biologics that inhibit their recruitment and activation (Frontiers in Immunology, 2021). However, because these cells are vital for host immunity, their suppression can lead to significant safety concerns, including increased susceptibility to opportunistic infections and neutropenia (PubMed, 2022).

Other names

Activated myeloid cellsInflammatory phagocytesActivated polymorphonuclear leukocytes and monocytes

Drugs modulate these cells by inhibiting chemotaxis and adhesion to the vascular endothelium, suppressing the production of pro-inflammatory mediators like TNF-alpha and IL-6, or inducing apoptosis to reduce the inflammatory burden (PubMed, 2022).