Janus kinase (JAK) is a family of intracellular, nonreceptor tyrosine kinases that play an important role in cytokine-mediated signaling. This family includes four protein kinases; Jak1, Jak2, Jak3 and Tyk2. Various studies have suggested that regulation of Jak activity should be a promising approach to combat numerous diseases such as immune deficiencies and cancers. The TYK2 (Tyrosine Kinase 2) Assay Kit is designed to measure TYK2 activity for screening and profiling applications using Kinase-Glo® MAX as a detection reagent. The TYK2 (Tyrosine Kinase 2) Assay Kit comes in a convenient 96-well format, with enough purified recombinant TYK2 enzyme, TYK2 substrate peptide (IRS-1tide), ATP and kinase assay buffer for 100 enzyme reactions.