Confocal microscopical analysis of polymerized F-actin on ATL cells. Resting normal T cells (A), ATL cells obtained from 2 representative ATL patients (B and C), and ATL cells pretreated with 1 μg/mL pertussis toxin (D) or 100 nmol/L wortmannin (E) for 2 hours at 37°C were incubated on fibronectin-coated slides for 1 minute, and the F-actin in these cells was stained with rhodamine-phalloidin and was observed by confocal microscopy (original magnification ×1,000).