Bile acid-induced EGFR activation in quiescent hepatic stellate cells can trigger both, proliferation and apoptosis

Quiescent HSC are fairly resistant to CD95-mediated apoptosis and CD95L [1] as well as hydrophobic bile acids [2] have been shown to activate EGFR in those cells. In addition, qHSC express CD133 and might represent a hepatic stem/progenitor cell compartment [3]. Rat HSC were cultured for 1–2 days. Activation of EGFR, Src and MAP kinases was measured by W.blot. CD95 was immunoprecipitated and detected for EGFR-association, Tyr-phosphorylation and DISC-formation. ROS-generation was measured by DCFDA-fluorescence. Proliferation and apoptosis were analyzed by BrdU-incorporation and TUNEL-staining, respectively. In q…