T-helper type 2 cell differentiation upon in vitro atorvastatin treatment. Naïve T cells isolated from transgenic interleukin (IL)-4-reporter (green fluorescent protein (GFP)-enhanced transcript) mice were incubated with 1, 5 or 10 μM atorvastatin (AT) either 4 hours prior to stimulation (preincubation; (a), (c)) or continuously while stimulated ((b), (d)) with 0.5 μg/ml αCD3 and 1 μg/ml αCD28. Expression of IL-4-reporting GFP was evaluated by fluorescence-activated cell sorting at the time-point indicated. (d) Expansion of T cells was visualized by forward scatter (FSC)–side scatter (SSC). Shown is one representative out of three independent experiments.