{"term":{"id":"11303","title":"thymus","longtitle":"IUPAC Gold Book - thymus","doi":"10.1351\/goldbook.11303","code":"11303","status":"current","definitions":[{"id":1,"text":"Pyramid-shaped organ in the thoracic or cervical region of mammals, composed of lymphatic tissue in which minute concentric bodies (thymic corpuscles, the remnants of epithelial structures) are found.","notes":{"1":"Stem cells in the outer cortex of thymus develop into different kinds of T cells. Some migrate to the inner medulla and enter the bloodstream; those that do not may be destroyed to prevent autoimmune reactions.","2":"This organ is necessary for the development of thymus-derived lymphocytes (T cells) and is the source of several hormones involved in T-cell maturation, for example, thymosin, thymopoietin, thymulin, and thymocyte humoral factor.","3":"If a newborn’s thymus is removed, not enough T cells are produced, the spleen and lymph nodes have little tissue, and the immune system fails, causing a gradual, fatal wasting disease. Thymus removal in adults has little effect."},"links":[{"term":"epithelial","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/10674"},{"term":"lymphatic","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/10904"},{"term":"medulla","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/10925"}],"sources":["PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 813 (https:\/\/doi.org\/10.1515\/pac-2015-1202)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/11303\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/11303\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/11303\/plain"},"citation":"Citation: 'thymus' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.11303","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-07-13T14:36:49+00:00"}}