Discovery of a JAK3-Selective Inhibitor: Functional Differentiation of JAK3-Selective Inhibition over pan-JAK or JAK1-Selective Inhibition.
Telliez, J.B., Dowty, M.E., Wang, L., Jussif, J., Lin, T., Li, L., Moy, E., Balbo, P., Li, W., Zhao, Y., Crouse, K., Dickinson, C., Symanowicz, P., Hegen, M., Banker, M.E., Vincent, F., Unwalla, R., Liang, S., Gilbert, A.M., Brown, M.F., Hayward, M., Montgomery, J., Yang, X., Bauman, J., Trujillo, J.I., Casimiro-Garcia, A., Vajdos, F.F., Leung, L., Geoghegan, K.F., Quazi, A., Xuan, D., Jones, L., Hett, E., Wright, K., Clark, J.D., Thorarensen, A.(2016) ACS Chem Biol 11: 3442-3451
- PubMed: 27791347 
- DOI: https://doi.org/10.1021/acschembio.6b00677
- Primary Citation of Related Structures:  
5TOZ - PubMed Abstract: 
PF-06651600, a newly discovered potent JAK3-selective inhibitor, is highly efficacious at inhibiting γc cytokine signaling, which is dependent on both JAK1 and JAK3. PF-06651600 allowed the comparison of JAK3-selective inhibition to pan-JAK or JAK1-selective inhibition, in relevant immune cells to a level that could not be achieved previously without such potency and selectivity. In vitro, PF-06651600 inhibits Th1 and Th17 cell differentiation and function, and in vivo it reduces disease pathology in rat adjuvant-induced arthritis as well as in mouse experimental autoimmune encephalomyelitis models. Importantly, by sparing JAK1 function, PF-06651600 selectively targets γc cytokine pathways while preserving JAK1-dependent anti-inflammatory signaling such as the IL-10 suppressive functions following LPS treatment in macrophages and the suppression of TNFα and IL-1β production in IL-27-primed macrophages. Thus, JAK3-selective inhibition differentiates from pan-JAK or JAK1 inhibition in various immune cellular responses, which could potentially translate to advantageous clinical outcomes in inflammatory and autoimmune diseases.
Organizational Affiliation: 
Inflammation and Immunology, Pfizer Worldwide R&D , 610 Main Street, Cambridge, Massachusetts 02139, United States.