A cytokine belonging to the type 1 interferon family, Interferon beta (IFN beta) binds IFN alpha/beta receptors (IFNAR) that activate tyrosine kinases and initiate the interferon-induced Jak-STAT signaling pathway, which modulates many key immune processes (Smieja et al.). In an experimental model involving cardiac fibroblasts isolated from rats, IFN beta was found to induce both pro- and anti-inflammatory cytokines production by activating different STAT proteins (Bolivar et al.). The anti-inflammatory effects of IFN beta have been studied in the context of autoimmune disorders, and there are currently multiple approved IFN beta drugs for treatment of relapsing forms of multiple sclerosis (Filipi and Jack). IFN beta is produced by immune cells, including macrophages, and non-immune cells, such as fibroblasts and epithelial cells (Ivashkiv and Donalin). The crystal structure of IFN beta shares characteristics with other type I interferons. It comprises five alpha-helices with four of them forming a helix bundle, and one long and three shorter loops connecting the helices (Karpusas et al.). For consistency and reproducibility across your applications, interferon alpha 1 from STEMCELL comes lyophilized with ≥ 87% purity, specific activity EC50 ≤ 18 pg/mL, and LAL analysis verification ensuring endotoxin levels are ≤ 1.0 EU/μg protein.