|IL-6 is an interleukin that acts as both a pro-inflammatory cytokine and an anti-inflammatory myokine. It is the originating member of a family of related cytokines that include IL-11, oncostatin M (OSM), leukemia inhibitory factor (LIF), ciliary neurotrophic factor (CNTF), cardiotrophin-1 (CT-1), cardiotrophin-like cytokine factor 1/B-cell stimulating factor 3 (NNT-1), neuropoietin (NPN), IL-27, and IL-31 . IL-6 is produced by T and B cells, macrophages, dendritic cells, and non-immune cells such as fibroblasts, endothelial cells, glial cells, keratinocytes, and placental syncytio- and extravillous trophoblasts.
The receptors for these cytokines (except IL-31) share a common signal transducing subunit gp130 (IL6ST).
IL-6 is a critical regulator of the immune system and has been widely implicated in autoimmune disease, infection responses and in the regulation of metabolic, regenerative, and neural processes.