Phospho-Jak1 (Tyr1034/1035) (F11) rabbit mAb

Jak1 plays an essential role in the IFN-α and IFN-γ response pathways and is tyrosine-phosphorylated upon cellular exposure to these signals. Jak1 oral inhibitors have been used to benefit patients with advanced myelofibrosis, where Jak1 was initially shown to be constitutively active in the peripheral blood cells of these patients. Targeted, small-molecule Jak inhibitors have also been used for treatment of rheumatoid arthritis. In cases of advanced melanoma, acquired resistance to PD-1 blockade drugs is associated with loss-of-functions of mutations in Jak1/2 genes. These mutations block interferon gamma signaling and prevent programmed death ligand 1 (PD-L1) expression in tumor cells.