Effects of purvalanol A on Mcl‐1 expression in neutrophils and peripheral blood mononuclear cells (PBMCs). Cells were incubated in the absence (untreated or ○) or presence of 30 µM purvalanol A (purvalanol or ●) for 2, 4 and 6 h before preparation for Western blotting for myeloid cell leukaemia factor‐1 (Mcl‐1) (40 kDa) and β‐actin (42 kDa), quantified by densitometry. (a,c) Typical Western blots; (b,d) densitometric analyses, expressed as a % of untreated control samples at time zero (± standard error of the mean, n = 3), *P ≤ 0·05 (paired two‐tailed Student's t‐test). Western blots shown are representative of n = 3 experiments.