IL-1β (Interleukin-1 beta) is a crucial pro-inflammatory cytokine primarily produced by activated monocytes and macrophages, but it can also be expressed in various cell types, including epithelial cells, endothelial cells, fibroblasts, synovial cells, neurons, mast cells, and glial cells. The biological functions of IL-1β are extensive, and it is involved in various autoimmune inflammatory responses and cellular activities, including cell proliferation, differentiation, and apoptosis. It also participates in the regulation of IL-6 and TNF-α and activates vascular adhesion molecules such as ICAM1. IL-1β plays a key role in the acute-phase response, including fever, acute protein synthesis, anorexia, and somnolence.