Interstitial migration of wild-type and RAPL-deficient T cells analyzed by intravital 2-photon microscopy. (A) Representative tracks of wild-type T cells (red) and RAPL^−/− T cells (green) in popliteal LN. Each line represents a single T-cell track. (B) Displacement and velocity profiles of wild-type T cells and RAPL-deficient T cells. Forty cells of each type were tracked for 30 minutes for each dataset. *P < .001, compared with wild-type cells.