Our current understanding of the lymphatics of the brain and spinal cord

Abstract

The lymphatic system, segregated from the blood vascular system, is an essential anatomical route along which interstitial fluid, solutes, lipids, immune cells, and cellular debris, are conveyed. However, the way these mechanisms operate within the cranial compartment is mostly unknown. Herein, we review current understanding of the meningeal lymphatics, described anatomically over a century ago yet still poorly understood from a functional standpoint. We will delineate the cellular mechanisms by which the meningeal lymphatics are formed and discuss their unique anatomy. Furthermore, this review will discuss the recently‐coined “glymphatic system” and the manner by which cerebrospinal fluid (CSF) and interstitial fluid (ISF) are exchanged and thus drained by the meningeal lymphatic vasculature as a key route for conveying cellular waste, solutes, and immune traffic to the deep cervical lymph nodes. The clinical relevance of the meningeal lymphatics will also be described, as they are relevant to various common defects of the lymphatic system. Clin. Anat. 32:117–121, 2019. © 2018 Wiley Periodicals, Inc.

Mengenal gambaran ultrasound lesi jinak, ganas dan metastasis pada nodus limfa leher menggunakan ultrasonografi

“…Pengetahuan yang mendalam tentang jaringan dan lokasi nodus limfa memungkinkan ditegakkan diagnossa secara benar serta menentukan kondisi metastase. 4,5,6,7,8 Nodus limfa hadir di seluruh tubuh secara berkelompok, besar terletak di dalam jalur yang berdekatan dengan struktur penting di dalam tubuh. 3 Dalam sistem limfatik, nodus limfa merupakan organ limfoid sekunder.…”

“…4 Nodus limfa mengandung limfosit B dan T. 4,5 Sel B banyak ditemukan pada daerah korteks luar, ditemukan secara berkelompok dalam sebuah folikel sedangkan sel T dan sel dendritik ditemukan di lapisan parakorteks. [6][7][8][9] Nodus limfa secara anatomi terbagi dalam kompartemen yang disebut nodul/lobulus, tiap kompartemen terdiri dari daerah korteks yang bersisikan gabungan sel B dan sel T, daerah paracortex didominasi oleh sel T, dan sebagian lagi berada pada medula. 6,7 Korteks nodus limfa adalah bagian terluar kelenjar, di bawahnya terdapat kapsul dan sinus subkapsular.…”

“…[6][7][8][9] Nodus limfa secara anatomi terbagi dalam kompartemen yang disebut nodul/lobulus, tiap kompartemen terdiri dari daerah korteks yang bersisikan gabungan sel B dan sel T, daerah paracortex didominasi oleh sel T, dan sebagian lagi berada pada medula. 6,7 Korteks nodus limfa adalah bagian terluar kelenjar, di bawahnya terdapat kapsul dan sinus subkapsular. Nodus limfa memiliki bagian dalam yang dikenal sebagai parakorteks.…”

Neuro-Inflammation in Pediatric Traumatic Brain Injury—from Mechanisms to Inflammatory Networks

“…When brain cells are damaged following a TBI, integral proteins, including myelin basic protein (MBP) [125], GFAP [126], and S100β [127], leak into the circulation and surrounding tissue and are taken up by APCs. Once the APCs enter the lymphatic system via the meningeal lymphatic vessels [128] and the recently characterized glymphatic system [129], they present these and other antigens to immature CD4 + and CD8 + T cells in the thymus and B cells in the lymph nodes and spleen, where they can activate and propagate the immune response to TBI. However, in other studies, T cell infiltration, namely T cells specific to MBP, can be neuroprotective by reducing retinal ganglion cell loss after axotomy in the adult rat [130].…”

Neural Stem Cells Secreting Bispecific T Cell Engager to Induce Selective Anti-Glioma Activity

“…The development of treatments for lessening the immunosuppressive effects of GBM represents an active area of preclinical and clinical neuro-oncology research. Many, if not all, approaches being tested involve increasing T cell cytotoxic anti-tumor activity [10][11][12][13][14][15][16].…”