title: The earliest thymic progenitors in adults are restricted to T, NK, and dendritic cell lineage and have a potential to form more diverse TCRbeta chains than fetal progenitors.
abstract: T cell progenitors in the adult thymus (AT) are not well characterized. In the present study, we show that the earliest progenitors in the murine AT are, like those in fetal thymus (FT), unable to generate B or myeloid cells, but still retain the ability to generate NK cells and dendritic cells. However, AT progenitors are distinct from those in FT or fetal liver, in that they are able to produce approximately 100 times larger numbers of T cells than progenitors in fetuses. Such a capability to generate a large number of T cells was mainly attributed to their potential to extensively proliferate before the TCRbeta chain gene rearrangement. We propose that the AT is colonized by T/NK/dendritic cell tripotential progenitors with much higher potential to form diversity in TCRbeta chains than FT progenitors.
authors.affiliation: Laboratory for Lymphocyte Development, RIKEN Research Center for Allergy and Immunology, Yokohama, Japan.
authors.forename: Min
authors.initials: M
authors.lastname: Lu
authors.forename: Risa
authors.initials: R
authors.lastname: Tayu
authors.forename: Tomokatsu
authors.initials: T
authors.lastname: Ikawa
authors.forename: Kyoko
authors.initials: K
authors.lastname: Masuda
authors.forename: Isamu
authors.initials: I
authors.lastname: Matsumoto
authors.forename: Hideo
authors.initials: H
authors.lastname: Mugishima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawamoto
authors.forename: Yoshimoto
authors.initials: Y
authors.lastname: Katsura
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology; D002454:Cell Differentiation; D019070:Cell Lineage; D003713:Dendritic Cells / Q000166:cytology*; D005333:Fetus / Q000166:cytology*; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D007694:Killer Cells, Natural / Q000166:cytology*; D051379:Mice; D008810:Mice, Inbred C57BL; D013601:T-Lymphocytes / Q000166:cytology*; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology