Cell-permeable. A selective protein kinase C (PKC) inhibitor (IC₅₀ =0.66 µM). Chelerythrine is at least 100-fold more selective for PKCs than for other kinases. It induces apoptotic cell death in polymorphonuclear leukocyte through activation of caspase-3. In addition, Chelerythrine treated cells underwent apoptosis, with features that suggest involvement of the mitochondrial pathway, and through a mechanism that involves inhibition of the anti-apoptotic inhibitor BclXL.