[CAS NO. 1159824-67-5]  CZC24832

CZC24832 has excellent selectivity to PI3Kγ. Out of the 154 identified lipid and protein kinases and the 922 other proteins, only two off targets (PI3Kβ and PIP4K2C) are detected within a 100-fold selectivity window. Despite the high sequence conservation of the human and rodent class I PI3K isoforms, the potency of CZC24832 for PI3Kγ and PI3Kβ is consistently lower by a factor of 2 to 4 in mice and rats compared to humans, but selectivity windows are largely retained. In the BT system, treatment with CZC24832 results in profound inhibition of IL-17A (IC50 =1.5 μM) as well as of B-cell activation markers such as IL-6 and IgG. In addition, strong inhibition of IL17A production is observed in T-cell systems such as human umbilical vein endothelial cells grown in the presence of TH2 blasts, indicating a general role for PI3Kγ kinase activity in the control of TH17 function. Thus, CZC24832 inhibits TH17 cell differentiation.