Actin stress-fiber formation in the stably transfected CHO-K1 cells adhering on immobilized fibrinogen. Cells were seeded on fibrinogen-coated surfaces (in the presence of 10 μg/mL mAb LM609) and incubated at 37°C for 1 hour in the presence or absence of 1 mM DTT. After fixation and permeabilization, the adhering cells were stained with phalloidin conjugated with Alexa Fluor 546 and anti-αIIb mAb PT25–2 conjugated with Alexa Fluor 488. The stained cells were subjected to confocal microscopy. Scale bar represents 10 μm.