Ontogeny of the immune system: γ/δ and α/β T cells migrate from thymus to the periphery in alternating waves

• Type of Material: Article
• Authors: D. Dunon, Centre National de la Recherche Scientifique Unitè de Recherche Associée; D. Courtois, Centre National de la Recherche Scientifique Unitè de Recherche Associée; O. Vainio, Turku University; A. Six, University of Alabama at Birmingham; C.H. Chen, University of Alabama at Birmingham; Max Cooper, Emory University; J.P. Dangy, Basel Institute for Immunology; B.A. Imhof, Basel Institute for Immunology
• Language: English
• Date: 1997-10-06
• Publisher: Rockefeller University Press
• Publication Version: Final Published Version
• Copyright Statement: © Rockefeller University Press.
• Final Published Version (URL): http://dx.doi.org/10.1084/jem.186.7.977
• Title of Journal or Parent Work: Journal of Experimental Medicine
• ISSN: 0022-1007
• Volume: 186
• Issue: 7
• Start Page: 977
• End Page: 988
• Grant/Funding Information: This work was supported by the Association pour la Recherche contre le Cancer, Association pour la Recherche contre le Cancer (ARC), the Human Frontier Science Programme Organization, Human Fronten Science Programme Organisation (HFSP), and the Academy of Finland. The Basel Institute for Immunology was founded and is supported by F. Hoffmann-La Roche (Basel, Switzerland).
• Keywords: STEM-CELLS; MICROENVIRONMENTS; CYCLIC RENEWAL; Research & Experimental Medicine; LYMPHOCYTE PRECURSOR CELLS; MURINE THYMUS; Immunology; DIFFERENTIATION; Life Sciences & Biomedicine; REGULATED EXPRESSION; RECEPTOR
• Research Categories: Health Sciences, Immunology; Biology, Microbiology

Abstract

The embryonic thymus is colonized by the influx of hemopoietic progenitors in waves. To characterize the T cell progeny of the initial colonization waves, we used intravenous adoptive transfer of bone marrow progenitors into congenic embryos. The experiments were performed in birds because intravenous cell infusions can be performed more efficiently in avian than in mammalian embryos. Progenitor cells, which entered the vascularized thymus via interlobular venules in the capsular region and capillaries located at the corticomedullary junction, homed to the outer cortex to begin thymocyte differentiation. The kinetics of differentiation and emigration of the T cell progeny were analyzed for the first three waves of progenitors. Each progenitor wave gave rise to γ/δ T cells 3 d earlier than α/β T cells. Although the flow of T cell migration from the thymus was uninterrupted, distinct colonization and differentiation kinetics defined three successive waves of γ/δ and α/β T cells that depart sequentially the thymus en route to the periphery. Each wave of precursors rearranged all three TCR Vγ gene families, but displayed a variable repertoire. The data indicate a complex pattern of repertoire diversification by the progeny of founder thymocyte progenitors.