Phenotype and localization of thymocytes expressing the homing receptor-associated antigen MEL-14: arguments for the view that most mature thymocytes are located in the medulla.

Détails

ID Serval
serval:BIB_3857D3AC1426
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Titre
Phenotype and localization of thymocytes expressing the homing receptor-associated antigen MEL-14: arguments for the view that most mature thymocytes are located in the medulla.
Périodique
Journal of Immunology
Auteur(s)
Shortman K., Wilson A., Van Ewijk W., Scollay R.
ISSN
0022-1767 (Print)
ISSN-L
0022-1767
Statut éditorial
Publié
Date de publication
1987
Volume
138
Numéro
2
Pages
342-351
Langue
anglais
Résumé
The monoclonal antibody MEL-14 recognizes a lymphocyte surface structure (the MEL-14 antigen) involved in migration of lymphocytes into lymph nodes. Its use as a maturation marker for T cells within the thymus led to the view that a small population (1 to 2%) of MEL-14high thymocytes located in the inner cortex represented fully mature cells about to exit as thymus emigrants. The medulla, in this view, contained only the phenotypically mature but MEL-14low cells, and was not the source of thymus emigrants. The data we present, derived from flow-cytometric analysis of suspension-stained CBA mouse thymocytes, is not in accordance with this view. A high proportion (approximately 20%) of thymocytes express relatively high levels of MEL-14; these include some immature Ly-2- L3T4- and nonmature Ly-2+ L3T4+ thymocytes. Among the 12 to 14% thymocytes of mature phenotype (PNAlow or H-2Khigh or Ly-2+ L3T4- and Ly-2- L3T4+), more than half express relatively high levels of MEL-14. The mature phenotype and MEL-14moderate-to-high cells (8% of thymocytes) appear too numerous to account for the few percent MEL-14high cells seen in the cortex in frozen sections, and the mature phenotype but MEL-14low cells (2 to 3% of thymocytes) too few to fill the medulla; however, both together account numerically for the medullary population. By section staining, the medulla contains Ly-2- L3T4+ and Ly-2+ L3T4- cells in a characteristic 2:1 ratio; by suspension staining this ratio agrees with that of the total mature phenotype population, but not with that of the MEL-14low subset previously claimed to represent medullary cells. Another paradox is apparent when suspension staining and section staining are compared: suspension staining reveals that many mature phenotype cells coexpress high levels of both MEL-14 and H-2K, yet section staining reveals H-2Khigh cells in the medulla but not in the inner cortex, and reveals scattered MEL-14high cells throughout the cortex but not in the medulla. We suggest that section staining for MEL-14 fails to locate the mature cells that stain for MEL-14 in suspension; the few MEL-14high cells localized in both the inner and the outer cortex on section staining are predominantly immature Ly-2- L3T4- and nonmature Ly-2+ L3T4+ thymocytes; the majority of thymocytes of mature phenotype, whether MEL-14high or MEL-14low on suspension staining, are of medullary location; the medulla is the most likely immediate source of thymic emigrants.
Mots-clé
Animals, Antigens, Surface/immunology, Cell Differentiation, H-2 Antigens/analysis, Lectins/diagnostic use, Mice, Mice, Inbred Strains, Peanut Agglutinin, Phenotype, Receptors, Immunologic/immunology, T-Lymphocytes/immunology, Thymus Gland/anatomy & histology, Thymus Gland/cytology
Pubmed
Web of science
Création de la notice
10/04/2013 12:44
Dernière modification de la notice
20/08/2019 13:27
Données d'usage