Effect of buthionine sulphoximine (BSO) on CSC-induced epithelial wound closure in NCI-H292 and in PBEC. Mechanical wounds prepared in monolayers of NCI-H292 (panel A) or PBEC (panel B). Before wounding, the cultures were preincubated for 16 hours with BSO, followed by incubation for 72 h (NCI-H292; panel A) or 24 h (PBEC; panel B) with freshly prepared CSC (△; 1 AU/ml), TGF-α (◆; 20 ng/ml), medium alone (●), BSO (alone [▽] or in combination with 1 AU/ml of CSC [■]). Next the residual wound area was determined and used to calculate the % wound repair. The results of both the experiments are mean ± SEM of 3 independent experiments, each performed in triplicate. P < 0.03 vs CSC 1 AU/ml.