Ohtani Osamu, Ohtani Yuko
Department of Anatomy, Faculty of Medicine and Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Toyama, Japan.
Arch Histol Cytol. 2008 Sep;71(2):69-76. doi: 10.1679/aohc.71.69.
The lymph node comprises a critical crossroad for encounters between antigen presenting cells, antigens from lymph, and lymphocytes recruited into lymph nodes from the blood. The node consists of spaces lined with lymphatic endothelial cells and parenchyma. The former spaces can be divided into the subcapsular sinuses, lymphatic labyrinths in the deep cortex, intermediate sinuses, and medullary sinuses. The sponge-like framework of the node parenchyma is composed of collagen fibers invested with reticular cells. The parenchyma can be divided into the cortex, deep cortex, and medullary cord. Lymphocytes migrate from the node parenchyma into the lymphatic labyrinths in the deep cortex. Close to the labyrinths are high endothelial venules (HEVs), through which circulating lymphocytes enter the node parenchyma. HEVs strongly express Aquaporin-1, suggesting that HEVs are involved in the net absorption of water, but not protein, from lymph coming through afferent lymphatics. Many LYVE-1 positive sinus reticular cells (i.e., lymphatic endothelial cells) with attached macrophages form a network within the lumen of the medullary sinuses. Fluids and migrating cells arriving at the node preferentially flow through the subcapsular sinuses, intermediate sinuses, and medullary sinuses in this order. Fluids and migrating cells may also enter the cortex through gaps in the floor of the subcapsular sinuses.
淋巴结是抗原呈递细胞、淋巴中的抗原以及从血液募集到淋巴结中的淋巴细胞相互作用的关键枢纽。淋巴结由衬有淋巴管内皮细胞的间隙和实质组成。前者的间隙可分为被膜下窦、深层皮质中的淋巴迷路、中间窦和髓窦。淋巴结实质的海绵状框架由包绕网状细胞的胶原纤维组成。实质可分为皮质、深层皮质和髓索。淋巴细胞从淋巴结实质迁移到深层皮质的淋巴迷路。靠近迷路的是高内皮微静脉（HEV），循环中的淋巴细胞通过它进入淋巴结实质。高内皮微静脉强烈表达水通道蛋白-1，这表明高内皮微静脉参与从传入淋巴管进入的淋巴中对水而非蛋白质的净吸收。许多附着有巨噬细胞的LYVE-1阳性窦网状细胞（即淋巴管内皮细胞）在髓窦腔内形成一个网络。到达淋巴结的液体和迁移细胞优先按此顺序流经被膜下窦、中间窦和髓窦。液体和迁移细胞也可能通过被膜下窦底部的间隙进入皮质。
