Kindlin-3 is not required for chemokine-mediated T lymphocyte motility or microvillar collapse. (A) CCR7 expression on control and LAD-III Kindlin-3–null PB T cells determined by FACS analysis. (B) Left: The fraction of control or Kindlin-3–null PB T cells persistently locomoting over immobilized CCL21 (2 μg/mL). Results shown are the means of 4 fields of view. Right: Tracks of individual lymphocytes depicted in different shades of gray during 10-minute tracking periods. Average velocities (mean ± SD) in each experimental group are indicated (n = 15). (C) CCL21, but not TCR, signals induce similar microvillar collapse in both control and Kindlin-3–null T lymphocytes. Scanning electron microscopic images of control and Kindlin-3–null T lymphocytes untreated or stimulated for 2 minutes with the TCR-ligating mAb OKT3 (10 μg/mL) or with soluble CCL21 (10nM). Scale bar represents 3 μm. Micrographs are representative of > 55 cells analyzed in each experimental group.