Saltar al contento

Thymo

De Wikipedia, le encyclopedia libere

Thymo[1] es un organo lymphoide primari locate in parte superior de thorace, post le manubrio sternal. Es componite de duo lobos con central medulla, circumferite de un cortice, e contenite in un capsula.

Iste glandula endocrin joca un rolo fundamental in immunitate adaptative. Permitte le maturation del lymphocytos T, ubi illos se differentia per acquisition de T-cell receptor (TCR, un glycoproteina membranari) e coreceptores CD4 e CD8 (in 80 % del casos).

Thymo es componite de thymocytos (immature T cellulas) con epithelial cellulas permittente lor disveloppamento in T cellulas compatibile con "antigenes de se" presentate per le complexo majeur de histocompatibilitate (CMH) (positive selection) e non contra proteinas del corpore (negative selection).[2][3][4] Positive selection occurre in thymic cortice e negative selection in thymic medulla.[5] Iste processo es parmittite per hormones e cytokins secretate in thymo, includente thymulina, thymopoietina e thymosinas.

Thymo es le plus grande e active durante neonatal e preadolescente periodos. Postea, thymic grandor e activitate regressa e su texitos son reimplaciate in parte per texito grasse. Nonobstante, alcun T cell disveloppamente continue al etate adulte. Un studio monstra le importantia del thymo pro adultos e que personnas habente subite un thymectomia (thymo ablation) ha un risco superior de disveloppar un cancere.[6][7]

Referentias[modificar fonte]

  1. Derivationes: (la) Thymus (glandula); (el) Θύμος αδένας - (de) Thymus; (en) Thymus; (pt) Timo; (es) Timo; (ca) Tim; (fr) Thymus (anatomie); (it) Timo (anatomia); (ro) Timus; (ru) Тимус
  2. https://www.medecinesciences.org/en/articles/medsci/full_html/2017/06/medsci2017336-7p653/medsci2017336-7p653.html
  3. (2016) Guyton and Hall textbook of medical physiology, 13th, Philadelphia: Elsevier, 466–7. ISBN 978-1-4557-7016-8. 
  4. (2014-08-27) Robbins and Cotran Pathologic Basis of Disease, 9th (online). ISBN 9780323296397. 
  5. (2019) "6. Cell mediated defence against infection: Thymic selection of CD4+ and CD8+ T Cells", Mandell, Douglas, and Bennett's principles and practice of infectious diseases, 9th (online), Elsevier. ISBN 9780323482554. 
  6. https://www.pourquoidocteur.fr/Articles/Question-d-actu/44633-Cette-glande-jugee-inutile-aiderait-lutter-cancer
  7. Kameron A. Kooshesh, Brody H. Foy, D.Phil., David B. Sykes, Karin Gustafsson & David T. Scadden (2023-08-03). "Health Consequences of Thymus Removal in Adults". The New England Journal of Medicine. doi:10.1056/NEJMoa2302892.