PCI-32765, also named as Ibrutinib, is a Bruton tyrosine kinase inhibitor which is used to study the biological effects of Bruton tyrosine kinase inhibition on mature B-cell function and the progression of B cell-associated diseases in vivo. The Bruton tyrosine kinase is specifically necessary for BCR signaling as demonstrated by human and mouse mutations that disrupt Bruton tyrosine kinase function and prevent B-cell maturation at steps which need a functional BCR pathway. PCI-32765 also inhibited autoantibody production. Occupancy of the Bruton tyrosine kinase active site by PCI-32765 was monitored in vitro and in vivo using a fluorescent affinity probe for Bruton tyrosine kinase.
Lee A. Honigberga, Ashley M. Smitha, Mint Sirisawada, Erik Vernera, David Lourya, Betty Changa, Shyr Lib, Zhengying Panb,d, Douglas H. Thamme, Richard A. Millera, and Joseph J. Buggya. The Bruton tyrosine kinase inhibitor PCI-32765 blocks B-cell activation and is efficacious in models of autoimmune disease and B-cell malignancy. PNAS. 2010; 107(29): 13075 – 80.