Tofacitinib citrate, also known as CP-690550 citrate, is a potent inhibitor of janus kinase 3 (JAK3), a hematopoetic cell-restricted tyrosine kinase involved in signal transduction regulating lymphocyte survival, proliferation, differentiation, and apoptosis. The inhibition is JAK3 specific with a selectivity 1000-fold more than other non-JAK family kinases. Besides inhibiting JAKS (IC50 = 1 nM), tofacitinib citrate also inhibits janus kinase 2 (JAK2) and janus kinase 1 (JAK1) with 20- and 100-fold less in potency respectively. However, in a recent study, the binding affinities (Ki) of tofacitinib citrate towards JAK1, JAK2, and JAK3 were reported to be 1.6 nM, 21.7 nM, and 6.5 nM respectively.
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Tofacitinib citrate is an orally available JAK1/2/3 inhibitor with IC50s of 1, 20, and 112 nM, respectively. Tofacitinib citrate has antibacterial, antifungal and antiviral activities.
4°C, protect from light
*In solvent : -80°C, 6 months; -20°C, 1 month (protect from light)