High endothelial venules

The structure of high endothelial venules (HEVs) is shown to advantage in these thin plastic sections. The unique cuboidal-shaped endothelial cells facilitate the migration (diapedesis) of lymphocytes from the blood into the surrounding tissues. These venules are surrounded by diffuse lymphoid tissue. HEVs are present in all secondary lymphoid tissues and organs except the spleen. The two images on the left show cross sections; the image on the right is a longitudinal section. Lymph node, 600x (left panels); 400x (right panel)

The structure of high endothelial venules (HEVs) is shown to advantage in these thin plastic sections. The unique cuboidal-shaped endothelial cells facilitate the migration (diapedesis) of lymphocytes from the blood into the surrounding tissues. These venules are surrounded by diffuse lymphoid tissue. HEVs are present in all secondary lymphoid tissues and organs except the spleen. The two images on the left show cross sections; the image on the right is a longitudinal section. Lymph node, 600x (left panels); 400x (right panel)

The structure of high endothelial venules (HEVs) is shown to advantage in these thin plastic sections. The unique cuboidal-shaped endothelial cells facilitate the migration (diapedesis) of lymphocytes from the blood into the surrounding tissues. These venules are surrounded by diffuse lymphoid tissue. HEVs are present in all secondary lymphoid tissues and organs except the spleen. The two images on the left show cross sections; the image on the right is a longitudinal section. Lymph node, 600x (left panels); 400x (right panel)