Lymphatic endothelium

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The lymphatic endothelium refers to a specialized subset of endothelial cells located in the sinus systems of draining lymph nodes. Specifically, these endothelial cells line the branched sinus systems formed by afferent lymphatic vessels, forming a single-cell layer which functions in a variety of critical physiological processes. These lymphatic endothelial cells contribute directly to immune function and response modulation, provide transport selectivity, and demonstrate orchestration of bidirectional signaling cascades. Additionally, lymphatic endothelial cells may be implicated in downstream immune cell development as well as lymphatic organogenesis. (Jalkanen, S., Salmi, M. 2020) [1] Until recently, lymphatic endothelial cells have not been characterized to their optimal potential. This system is very important in the function of continuous removal of interstitial fluid and proteins, while also having a significant function of entry for leukocytes and tumor cells. This leads to further research that is being developed on the relationship between lymphatic endothelium and metastasis of tumor cells (Pepper, M. S., & Skobe, M. 27 October 2003). [2] The lymphatic capillaries are described to be blind ended vessels (closed on one end), and they are made up of a single non-fenestrated layer of endothelial cells; The lymph capillaries function to aid in the uptake of fluids, macromolecules, and cells. Although they are generally similar to blood capillaries, the lymph capillaries have distinct structural differences. Lymph capillaries consist of a more wide and irregular lumen, and the endothelium in lymph capillaries is much thinner as well (S. Pepper, Skobe 2003). Their origin has been speculated to vary based on them being dependent on specific tissue environments, and powered by organ-specific signals.(L. Gutierrez-Miranda, K. Yaniv, 2020). [3] A lymph capillary endothelial cell is distinct from other endothelial cells in that collagen fibers are directly attached to its plasma membrane.

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Although lymphatics were first described by Hippocrates in 400 BC and rediscovered as "milky veins in the gut of a well fed dog" in the 17th century by Gasparo Aselli, they were ignored for centuries until in 1937 Howard Florey showed that lymphatics enlarge in inflammation. At this stage vascular and lymphatic endothelia were seen to be morphologically distinct and lymphatic vessels considered less important. Later it was discovered that VEGF-R3 and VEGF-C/VEGF-D were the key growth factors controlling lymphatic endothelial proliferation. Markers of lymphatic endolthelium were not discovered until relatively recently. These being LYVE-1 (Jackson et al., 1999) [4] and podoplanin (Kerjaschki, 1999). [5]

See also

Related Research Articles

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<span class="mw-page-title-main">Angiogenesis</span> Blood vessel formation, when new vessels emerge from existing vessels

Angiogenesis is the physiological process through which new blood vessels form from pre-existing vessels, formed in the earlier stage of vasculogenesis. Angiogenesis continues the growth of the vasculature mainly by processes of sprouting and splitting, but processes such as coalescent angiogenesis, vessel elongation and vessel cooption also play a role. Vasculogenesis is the embryonic formation of endothelial cells from mesoderm cell precursors, and from neovascularization, although discussions are not always precise. The first vessels in the developing embryo form through vasculogenesis, after which angiogenesis is responsible for most, if not all, blood vessel growth during development and in disease.

<span class="mw-page-title-main">Endothelium</span> Layer of cells that lining inner surface of blood vessels

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<span class="mw-page-title-main">Lymphatic vessel</span> Tubular vessels that are involved in the transport of lymph and lymphocytes

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<span class="mw-page-title-main">C-fos-induced growth factor</span> Mammalian protein found in humans

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<span class="mw-page-title-main">PDPN</span>

Podoplanin is a protein that in humans is encoded by the PDPN gene.

<span class="mw-page-title-main">PROX1</span> Protein-coding gene in the species Homo sapiens

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<span class="mw-page-title-main">LYVE1</span> Protein may function in lymphatic hyaluronan transport and have a role in tumor metastasis

Lymphatic vessel endothelial hyaluronan receptor 1 (LYVE1), also known as extracellular link domain containing 1 (XLKD1) is a Link domain-containing hyaladherin, a protein capable of binding to hyaluronic acid (HA), homologous to CD44, the main HA receptor. In humans it is encoded by the LYVE1 gene.

<span class="mw-page-title-main">STAB1</span> Protein-coding gene in the species Homo sapiens

Stabilin-1 is a protein that in humans is encoded by the STAB1 gene.

<span class="mw-page-title-main">CCBE1</span> Protein-coding gene in the species Homo sapiens

Collagen and calcium-binding EGF domain-containing protein 1 is a protein that in humans is encoded by the CCBE1 gene.

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<span class="mw-page-title-main">Meningeal lymphatic vessels</span>

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References

  1. ↑ Jalkanen, Sirpa; Salmi, Markko (24 February 2020). "Lymphatic endothelial cells of the lymph node". Nature Reviews Immunology. 20 (9): 566–578. doi:10.1038/s41577-020-0281-x. PMID   32094869. S2CID   211265611 . Retrieved 15 November 2023.
  2. ↑ Pepper, Michael S.; Skobe, Mihaela (27 October 2003). "Lymphatic endothelium". The Journal of Cell Biology. 163 (2): 209–213. doi:10.1083/jcb.200308082. PMC   2173536 . PMID   14581448.
  3. ↑ Gutierrez-Miranda, Laura; Karina, Yaniv (24 September 2020). "Cellular Origins of the Lymphatic Endothelium: Implications for Cancer Lymphangiogenesis". Frontiers in Physiology. 11: ePub. doi: 10.3389/fphys.2020.577584 . PMC   7541848 . PMID   33071831.
  4. ↑ Banerji, Suneale; Ni, Jian; Wang, Shu-Xia; Clasper, Steven; Su, Jeffrey; Tammi, Raija; Jones, Margaret; Jackson, David G. (1999). "LYVE-1, a new homologue of the CD44 glycoprotein, is a lymph-specific receptor for hyaluronan 1". The Journal of Cell Biology. 144 (4): 789–801. doi:10.1083/jcb.144.4.789. PMC   2132933 . PMID   10037799.
  5. ↑ Breiteneder-Geleff, Silvana; Soleiman, Afschin; Kowalski, Heinrich; Horvat, Reinhard; Amann, Gabriele; Kriehuber, Ernst; Diem, Katja; Weninger, Wolfgang; Tschachler, Erwin; Alitalo, Kari; Kerjaschki, Dontscho (1999). "Angiosarcomas express mixed endothelial phenotypes of blood and lymphatic capillaries: podoplanin as a specific marker for lymphatic andothelium". American Journal of Pathology. 154 (2): 385–394. doi:10.1016/S0002-9440(10)65285-6. PMC   1849992 . PMID   10027397.

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