Human thymic dendritic cells

Abstract

Human thymic dendritic cells (DC) represent a member of the bone marrow–derived dendritic cell family. They have a dendritic shape and are found in small numbers mainly at the corticomedullary border and in medullary regions of the thymus. Human thymic DC were isolated by density gradient separation, followed by treatment with CD2, CD7, CD1, and CD11b mAb and immunobeads magnetic separation. The resulting population contains 60–75% brightly HLA‐DR+ cells which present the morphological characteristics of DC observed in situ. Extensive phenotypic analysis confirmed that they are of mesenchymal origin and that some express CD11a and CD54 molecules. Freshly isolated DC do not stain with a wide variety of anti‐T‐B and ‐monocyte or ‐macrophage mAb. However, they acquire the CD1 molecule after a few days in culture. By using a cell sorter we obtained 90–95% of purified human thymic DC. Functional studies have shown that human thymic DC are potent activators in mixed lymphocyte reactions, act as accessory cells in mitogenic thymocyte proliferation, increase the thymocyte proliferative response to a toxin signal, and produce IL‐1. They also formed spontaneous physical associations with thymocytes, which raises questions about the implication of DC in differentiation and/or maturation processes of thymocytes. Microsc. Res. Tech. 38:267–275, 1997. © 1997 Wiley‐Liss, Inc.

Thymus and aging: morphological, radiological, and functional overview

“…TDCs are members of bone-marrow-derived DC family and develop inside the thymus (Savchenko et al 2006). They have a dendritic shape and are found mainly at the thymic CMJ and in the medullary region (Lafontaine et al 1997). The function of TDC is generating central T cell tolerance through the deletion or negative selection of autoreactive thymocytes (Ardavín et al 2001).…”

Development and maturation of thymic dendritic cells during human ontogeny

“…They have a dendritic shape and are found mainly at the corticomedullary border and in the medullary region of the thymus (Lafontaine et al 1997). The function of TDC is generating central T-cell tolerance through the deletion or negative selection of autoreactive thymocytes (Gaillard et al 1993;Vicente et al 1994;Shortman and Caux 1997;Ardavin 1997;Ardavin et al 2001;Vandenabeele et al 2001;Varas et al 2003).…”

Ανοσοφαινοτυπική Μελέτη Της Επιθηλιακής Κυτταρικής Διαφοροποίησης Του Θύμου

“…Το βασικό συστατικό της δομής του στρώματος περιλαμβάνει τα δικτυωτά θυμικά επιθηλιακά κύτταρα (TEC), που χαρακτηρίζονται σε υπερμικροσκοπικό επίπεδο από την παρουσία τονοϊνιδίων και συνδέσεις δεσμοσωματίων. (115)(116)(117)(118)(119)(120)(121)(122)(123) Στη φλοιική μοίρα του θύμου αδένα, τα επιθηλιακά κύτταρα έχουν Η πολυμορφία που παρατηρείται στο βασικό ιστολογικό προφίλ των επιθηλιακών κυττάρων του θύμου αδένα παρουσιάζεται και με βάση ανοσοφαινοτυπικές μελέτες με τη χρήση των κάτωθι αντισωμάτων: (124)(125)(126)(127) αντισώματα μορίων MHC τάξης Ι και ΙΙ, αντισώματα έναντι πολυπεπτιδίων της κυτοκερατίνης, αντισώματα έναντι των επιθηλιακών κυττάρων ανθρώπου (cluster of thymic epithelial staining, CTES). Επιπρόσθετα, σημαντική διαφοροποίηση παρατηρείται σε ότι αφορά στην έκκριση μιας σειράς ορμονών.…”