Interferon alfacon-1

Interferon alpha binds to type I interferon receptors (IFNAR1 and IFNAR2c) which, upon dimerization, activate two Jak (Janus kinase) tyrosine kinases (Jak1 and Tyk2). These transphosphorylate themselves and phosphorylate the receptors. The phosphorylated INFAR receptors then bind to Stat1 and Stat2 (signal transducers and activators of transcription) which dimerize and activate multiple (~100) immunomodulatory and antiviral proteins. Interferon alpha binds less stably to type I interferon receptors than interferon beta. The resulting actions include gene transcription, inhibition of cellular growth, alteration of the state of cellular differentiation, interference with oncogene expression, alteration of cell surface antigen expression, increasing phagocytic activity of macrophages, and augmentation of the cytotoxicity of lymphocytes for target cells.