Lymphocyte selective extravasation through the high endothelial venules of lymph nodes

淋巴细胞通过淋巴结高内皮小静脉选择性外渗

• 批准号: 11670012
• 负责人: KIKUTA Akio
• 金额: $ 0.45万
• 依托单位: University of Occupational and Environmental Health, Japan
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11670012/
• 关键词: lymphocyte homing; high endothelial venules; Lymph nodes; L-selectin; MAdCAM-1

The localization of two lymphocyte homing ligands, L-selectin ligand (LSL) and MAdCAM-1, were studied immuno-histochemically in order to reveal the mechanisms of the lymphocyte extravasation through the high endothelial venules (HEV) within the secondary lymphoid tissues. Most HEV within the peripheral lymph nodes (PLN) expressed LSL. Although the submandibular and deep cervical lymph nodes are PLN, some HEV in these lymph nodes expressed MAdCAM-1.In nasal associated lymphoid tissue (NALT), many HEV expressed LSL, while a few HEV expressed MAdCAM-1, showing an expression profile distinct from that of HEV in Peyer's patches, gut mucosal associated lymphoid tissues.Perfusion of the rat inguinal lymph nodes with a culture medium was performed to remove blood except for adhered lymphocytes to the HEV and to observe early morphological changes of the adhered lymphocytes and high endothelial cells (HEC). The HEV of the lymph nodes were observed by scanning and transmission electron microscopy. Adhered lymphocytes were considered to be round with many microvilli on their whole surface. Lymphocytes were then seemed to retract most microvilli other than those attached to the HEC on their tips. Next, lymphocytes were considered to become flatter to adhere to HEC with broader surfaces. These morphological changes might reflect the transition from the weak adhesion mediated by L-selectin and its ligands to the strong adhesion by LFA-1 and ICAM-1.The uneven distribution of microvilli on the some transforming lymphocytes suggests important roles of the microvilli in transition of the adhesion modes.

采用免疫组织化学方法研究了l -选择素配体（LSL）和MAdCAM-1两种淋巴细胞归巢配体的定位，以揭示淋巴细胞通过高内皮小静脉（HEV）在继发淋巴组织内外渗的机制。周围淋巴结（PLN）内大多数HEV表达LSL。虽然下颌下淋巴结和颈深淋巴结是PLN，但这些淋巴结中的一些HEV表达MAdCAM-1。在鼻相关淋巴组织（NALT）中，许多HEV表达LSL，而少数HEV表达MAdCAM-1，其表达谱与Peyer斑块（肠粘膜相关淋巴组织）中的HEV不同。用培养液灌注大鼠腹股沟淋巴结，除去黏附淋巴细胞外的血液，观察黏附淋巴细胞和高内皮细胞（HEC）的早期形态学变化。用扫描电镜和透射电镜观察淋巴结的HEV情况。黏附淋巴细胞呈圆形，整个表面有许多微绒毛。淋巴细胞似乎收缩了大部分微绒毛，而不是那些附着在HEC上的微绒毛。接下来，淋巴细胞被认为变得更平坦，粘附在具有更宽表面的HEC上。这些形态变化可能反映了由l -选择素及其配体介导的弱粘附向LFA-1和ICAM-1介导的强粘附的转变。微绒毛在部分转化淋巴细胞上分布不均，提示微绒毛在黏附模式转变中起重要作用。