Heterogeneity of epithelial cells in the rat thymus

✍ Scribed by De Waal, Eric J.; Rademakers, Louk H.P.M.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 781 KB
• Volume: 38
• Category: Article
• ISSN: 1059-910X
• DOI: 10.1002/(sici)1097-0029(19970801)38:3<227::aid-jemt4>3.0.co;2-j

✦ Synopsis

The morphological heterogeneity of the thymic epithelium has been well documented both at the light and electron microscopic level. Immunohistochemistry has revealed four broad classes of epithelial cells (EC): subcapsule/perivascular, cortical, medullary EC, and medullary Hassall's corpuscles. Ultrastructural analysis has revealed further heterogeneity. In the cortex, four EC subtypes have been described ultrastructurally: subcapsular/perivascular, "pale," "intermediate," and "dark" EC. These subtypes are also present in the medulla. Two additional EC subtypes are restricted to the medulla: an undifferentiated subtype, and a subtype displaying signs of high metabolic activity. Based on the morphological features of the epithelium, it has been hypothetized that the thymic EC subtypes represent a process of differentiation.