Ligation of LFA-1 by immobile mAbs generates stronger shear-resistant adhesions in normal than in Kindlin-3–deficient T cells. Spontaneous adhesion strengthening developed by PB T cells settled for 1 minute on surface-coated TS1.22 (anti-α_L; A), HP1.2 (anti-α₄; B), TS1.18 (anti-β₂; C), or CD29 (anti-β₁; D) antibodies. Cells were subjected to detachment by incremented shear forces, and the percentage of initially settled T cells that resisted detachment from the substrate at the indicated shear forces was determined in 2 fields of view. The values represent the means ± range. Each experiment shown is representative of 3.