Blockade of lymphocyte homing to LN induces the disappearance of HEV pockets. (A) Confocal images of LNs section from a RAG-2°/°ubiquitin-GFP chimera (green) injected or not intravenously for 1 hour with 100 μg of anti-CD62L blocking Ab (MEL-14) and stained for CD3 (red) and sytox 63/nuclei (blue). Arrowheads point to HEV pockets. (B) Height (and standard error) in arbitrary units of LN HEV (see “Morphoretic analysis of HEV”). Data are representative of 2 different experiments (2 mice per experiment, ∼ 15 analyzed HEVs for each condition per experiment).