F-actin flow is slowed by the addition of immobilized VCAM-1. Human T lymphoblasts were transduced with Lifeact-GFP (green) and allowed to interact with stimulatory coverglasses coated with anti-CD3, ICAM-1, and VCAM-1 (unlabeled). Confocal 0.5-µm-thick Z stacks were acquired near the coverslip by confocal microscopy using a spinning disk confocal microscope (Ultraview Perkin Elmer on an Axiovert 200 stand Carl Zeiss) every 2 s for 2 min and are shown as extended projections.
