Department of Anatomy, Division of Surgical Specialties, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands.
J Anat. 2020 Jan;236(1):156-164. doi: 10.1111/joa.13077. Epub 2019 Sep 9.
Omental milky spots (OMSs), small lymphoid structures positioned in the greater omentum, are involved in peritoneal immune homeostasis and the formation of omental metastases. Sympathetic nerve activity is known to regulate immune function in other lymphoid organs (e.g. spleen and lymph nodes) and to create a favourable microenvironment for various tumour types. However, it is still unknown whether OMSs receive sympathetic innervation. Therefore, the aim of this study was to establish whether OMSs of the adult human greater omentum receive sympathetic innervation. A total of 18 OMSs were isolated from five omenta, which were removed from 3% formaldehyde-perfused cadavers (with a median age of 84 years, ranging from 64 to 94). OMSs were embedded in paraffin, cut and stained with a general (PGP9.5) and sympathetic nerve marker (TH and DBH), and evaluated by bright field microscopy. A T-cell, B-cell, and macrophage staining was performed to confirm OMS identity. In 50% of the studied OMSs, sympathetic nerve fibres were observed at multiple levels of the same OMS. Nerve fibres were represented as dots or elongated structures and often observed in relation to small vessels and occasionally as individual structures residing between lymphoid cells. The current study shows that 50% of the investigated OMSs contain sympathetic nerve fibres. These findings may contribute to our understanding of neural regulation of peritoneal immune response and the involvement of OMSs in omental metastases.
大网膜乳斑（OMSs）是位于大网膜中的小型淋巴结构，参与腹膜免疫稳态和大网膜转移的形成。已知交感神经活动可调节其他淋巴器官（如脾脏和淋巴结）中的免疫功能，并为各种肿瘤类型创造有利的微环境。然而，OMSs 是否接受交感神经支配仍不清楚。因此，本研究旨在确定成人大网膜的 OMS 是否接受交感神经支配。从五个用 3%甲醛灌注的尸体（中位年龄 84 岁，范围为 64 岁至 94 岁）切除的大网膜中分离出总共 18 个 OMS。将 OMS 嵌入石蜡中，切片并用通用（PGP9.5）和交感神经标志物（TH 和 DBH）染色，并通过明场显微镜进行评估。进行 T 细胞、B 细胞和巨噬细胞染色以确认 OMS 的身份。在研究的 OMS 中，有 50%在同一 OMS 的多个水平观察到交感神经纤维。神经纤维表现为点状或长形结构，通常与小血管有关，偶尔也以单个结构存在于淋巴细胞之间。本研究表明，50%的研究 OMS 含有交感神经纤维。这些发现可能有助于我们理解腹膜免疫反应的神经调节以及 OMS 在大网膜转移中的作用。
