Hassall's corpuscles (or thymic corpuscles (bodies)) are structures found in the medulla of the human thymus, formed from eosinophilic type VI epithelial reticular cells arranged concentrically. These concentric corpuscles are composed of a central mass, consisting of one or more granular cells, and of a capsule formed of epithelioid cells. They vary in size with diameters from 20 to more than 100μm, and tend to grow larger with age.[1] They can be spherical or ovoid and their epithelial cells contain keratohyalin and bundles of cytoplasmic fibres.[2] Later studies indicate that Hassall's corpuscles differentiate from medullary thymic epithelial cells after they lose autoimmune regulator (AIRE) expression.[3] This makes them an example of Thymic mimetic cells.[4] They are named for Arthur Hill Hassall, who discovered them in 1846.[5][6]
The function of Hassall's corpuscles is currently unclear, and the absence of this structure in the thymus of most murine species (except for the New Zealand White Mouse strain) has previously restricted mechanistic dissection. It is known that Hassall's corpuscles are a potent source of the cytokineTSLP. In vitro, TSLP directs the maturation of dendritic cells, and increases the ability of dendritic cells to convert naive thymocytes to a Foxp3+ regulatory T cell lineage.[7][8] It is unknown if this is the physiological function of Hassall's corpuscles in vivo.
In the past decade, researchers found tissue-specific self-antigens in Hassall's corpuscles and revealed their role in the pathogenesis of diseases such as type 1 diabetes, rheumatoid arthritis, multiple sclerosis, autoimmune thyroiditis, Goodpasture's syndrome, and others. They also discovered that Hassall's corpuscles synthesize chemokines affecting different cell populations in thymic medulla. Despite this, the information on the relationship between Hassall's corpuscles with other cell types of thymic medulla (dendritic, myoid, neuroendocrine cells, thymocytes, macrophages, eosinophils, etc.) remains insufficient and often contradictory. Mechanisms of these relationships and their functional significance are still unclear. The lack of such data does not allow a systemic view of the differentiation processes in the thymus.
ReferencesEdit
This article incorporates text in the public domain from page 1274 of the 20th edition ofGray's Anatomy(1918)
^Geneser, Finn (1999). Histologi. Munksgaard Danmark. ISBN87-628-0137-6.
^Dorland's (2012). Dorland's Illustrated Medical Dictionary (32nd ed.). Elsevier. p. 419. ISBN978-1-4160-6257-8.
^Wang, Xiaoping; et al. (2012). "Post-Aire maturation of thymic medullary epithelial cells involves selective expression of keratinocyte-specific autoantigens". Front. Immunol. 3 (March): 19. doi:10.3389/fimmu.2012.00019. PMC3310317. PMID 22448160.
^Louis Kater: A Note on Hassall's Corpuscles. Contemporary Topics in Immunobiology Volume 2, 1973, pp. 101-109.
^Hassall, A. H., 1846. Microscopic Anatomy of the Human Body in Health and Disease, Highly, London.
^* Watanabe N, Wang Y, Lee H, Ito T, Wang Y, Cao W, Liu Y (2005). "Hassall's corpuscles instruct dendritic cells to induce CD4+CD25+ regulatory T cells in human thymus". Nature. 436 (7054): 1181–5. Bibcode:2005Natur.436.1181W. doi:10.1038/nature03886. PMID 16121185. S2CID 4387582.
^"Old mystery solved, revealing origin of regulatory T cells that 'police' and protect the body"
hassall, corpuscles, thymic, corpuscles, bodies, structures, found, medulla, human, thymus, formed, from, eosinophilic, type, epithelial, reticular, cells, arranged, concentrically, these, concentric, corpuscles, composed, central, mass, consisting, more, gran. Hassall s corpuscles or thymic corpuscles bodies are structures found in the medulla of the human thymus formed from eosinophilic type VI epithelial reticular cells arranged concentrically These concentric corpuscles are composed of a central mass consisting of one or more granular cells and of a capsule formed of epithelioid cells They vary in size with diameters from 20 to more than 100mm and tend to grow larger with age 1 They can be spherical or ovoid and their epithelial cells contain keratohyalin and bundles of cytoplasmic fibres 2 Later studies indicate that Hassall s corpuscles differentiate from medullary thymic epithelial cells after they lose autoimmune regulator AIRE expression 3 This makes them an example of Thymic mimetic cells 4 They are named for Arthur Hill Hassall who discovered them in 1846 5 6 Hassall s corpusclesMicrograph of a thymic corpuscle H amp E stain DetailsPart ofMedulla of thymusAnatomical terminology edit on Wikidata The function of Hassall s corpuscles is currently unclear and the absence of this structure in the thymus of most murine species except for the New Zealand White Mouse strain has previously restricted mechanistic dissection It is known that Hassall s corpuscles are a potent source of the cytokine TSLP In vitro TSLP directs the maturation of dendritic cells and increases the ability of dendritic cells to convert naive thymocytes to a Foxp3 regulatory T cell lineage 7 8 It is unknown if this is the physiological function of Hassall s corpuscles in vivo In the past decade researchers found tissue specific self antigens in Hassall s corpuscles and revealed their role in the pathogenesis of diseases such as type 1 diabetes rheumatoid arthritis multiple sclerosis autoimmune thyroiditis Goodpasture s syndrome and others They also discovered that Hassall s corpuscles synthesize chemokines affecting different cell populations in thymic medulla Despite this the information on the relationship between Hassall s corpuscles with other cell types of thymic medulla dendritic myoid neuroendocrine cells thymocytes macrophages eosinophils etc remains insufficient and often contradictory Mechanisms of these relationships and their functional significance are still unclear The lack of such data does not allow a systemic view of the differentiation processes in the thymus References Edit This article incorporates text in the public domain from page 1274 of the 20th edition of Gray s Anatomy 1918 Geneser Finn 1999 Histologi Munksgaard Danmark ISBN 87 628 0137 6 Dorland s 2012 Dorland s Illustrated Medical Dictionary 32nd ed Elsevier p 419 ISBN 978 1 4160 6257 8 Wang Xiaoping et al 2012 Post Aire maturation of thymic medullary epithelial cells involves selective expression of keratinocyte specific autoantigens Front Immunol 3 March 19 doi 10 3389 fimmu 2012 00019 PMC 3310317 PMID 22448160 Michelson Daniel A Mathis Diane October 2022 Thymic mimetic cells tolerogenic masqueraders Trends in Immunology 43 10 782 791 doi 10 1016 j it 2022 07 010 PMC 9509455 PMID 36008259 Louis Kater A Note on Hassall s Corpuscles Contemporary Topics in Immunobiology Volume 2 1973 pp 101 109 Hassall A H 1846 Microscopic Anatomy of the Human Body in Health and Disease Highly London Watanabe N Wang Y Lee H Ito T Wang Y Cao W Liu Y 2005 Hassall s corpuscles instruct dendritic cells to induce CD4 CD25 regulatory T cells in human thymus Nature 436 7054 1181 5 Bibcode 2005Natur 436 1181W doi 10 1038 nature03886 PMID 16121185 S2CID 4387582 Old mystery solved revealing origin of regulatory T cells that police and protect the body External links Editsynd 1912 at Who Named It UIUC Histology Subject 1247 Histology at KUMC lymphoid lymph03 Hassall s Corpuscles Histology image 61 05 at the University of Oklahoma Health Sciences Center Thymus Histology image 07407loa Histology Learning System at Boston University Lymphoid Tissues and Organs thymus Hassall s corpuscles Portal Anatomy Retrieved from https en wikipedia org w index php title Hassall 27s corpuscles amp oldid 1160102383, wikipedia, wiki, book, books, library,
