Jones Emma, Gallimore Awen, Ager Ann
Division of Infection and Immunity, School of Medicine and Systems Immunity Research Institute, Cardiff University, Heath Park, Cardiff, UK.
Methods Mol Biol. 2018;1845:99-118. doi: 10.1007/978-1-4939-8709-2_7.
High endothelial venules (HEVs) are structurally distinct blood vessels that develop during embryonic and neonatal life in all secondary lymphoid organs except the spleen. HEVs are critical for initiating and maintaining immune responses because they extract naïve and memory lymphocytes from the bloodstream, regardless of antigen receptor specificity, and deliver them to antigen-presenting cells inside lymph nodes under homeostatic conditions. HEVs also develop postnatally in nonlymphoid organs during chronic inflammation driven by autoimmunity, infection, allografts, and cancer. Extranodal HEVs are usually surrounded by dense lymphocytic infiltrates organized into lymph-node like, T- and B-cell-rich areas called tertiary lymphoid structures (TLS). HEV neogenesis is thought to facilitate the generation of tissue-destroying lymphocytes inside chronically inflamed tissues and cancers.We are studying the mechanisms underpinning HEV neogenesis in solid cancers and the role of homeostatic T-cell trafficking in controlling cancer immunity. In this chapter we describe methods for identifying HEV in tissue sections of cancerous tissues in humans and mice using immunohistochemical staining for the HEV-specific marker peripheral lymph node addressin (PNAd). L-selectin binding to PNAd is a necessary first step in homeostatic lymphocyte trafficking which is the defining function of HEV. We also describe methods to measure L-selectin-dependent homing of lymphocytes from the bloodstream into lymphoid tissues and tumors in preclinical cancer models.
高内皮微静脉（HEV）是结构独特的血管，在胚胎期和新生儿期除脾脏外的所有二级淋巴器官中发育。HEV对于启动和维持免疫反应至关重要，因为它们能从血流中提取幼稚和记忆淋巴细胞，而不考虑抗原受体特异性，并在稳态条件下将它们输送到淋巴结内的抗原呈递细胞。在自身免疫、感染、同种异体移植和癌症引发的慢性炎症期间，HEV也会在出生后在非淋巴器官中发育。结外HEV通常被密集的淋巴细胞浸润所包围，这些浸润组织形成类似淋巴结的富含T细胞和B细胞的区域，称为三级淋巴结构（TLS）。HEV新生被认为有助于在慢性炎症组织和癌症中产生破坏组织的淋巴细胞。我们正在研究实体癌中HEV新生的潜在机制以及稳态T细胞转运在控制癌症免疫中的作用。在本章中，我们描述了使用针对HEV特异性标志物外周淋巴结地址素（PNAd）的免疫组织化学染色来鉴定人和小鼠癌组织切片中HEV的方法。L-选择素与PNAd的结合是稳态淋巴细胞转运的必要第一步，而这是HEV的定义性功能。我们还描述了在临床前癌症模型中测量淋巴细胞从血流到淋巴组织和肿瘤的L-选择素依赖性归巢的方法。
