title: Identification of the earliest prethymic bipotent T/NK progenitor in murine fetal liver.
abstract: This article describes the isolation of a novel cell population (B220(lo)c-kit(+)CD19(-)) in the fetal liver that represents 70% of T-cell precursors in this organ. Interestingly, these precursors showed a bipotent T-cell and natural killer cell (NK)- restricted reconstitution potential but completely lacked B and erythromyeloid differentiation capacity both in vivo and in vitro. Moreover, not only mature T-cell receptor (TCR)alphabeta(+) peripheral T cells but also TCRgammadelta(+) and TCRalphabeta(+)CD8alphaalpha(+) intestinal epithelial cells of extrathymic origin were generated in reconstituted mice. The presence of this population in the fetal liver of athymic embryos indicates its prethymic origin. The comparison of the phenotype and differentiation potential of B220(lo)c-kit(+)CD19(-) fetal liver cells with those of thymic T/NK progenitors indicates that this is the most immature common T/NK cell progenitor so far identified. These fetal liver progenitors may represent the immediate developmental step before thymic immigration.
authors.affiliation: Unité du Développement des Lymphocytes, Département d'Immunologie, Institut Pasteur, Paris, France. idouagi@pasteur.fr
authors.forename: Iyadh
authors.initials: I
authors.lastname: Douagi
authors.forename: Francesco
authors.initials: F
authors.lastname: Colucci
authors.forename: James P
authors.initials: JP
authors.lastname: Di Santo
authors.forename: Ana
authors.initials: A
authors.lastname: Cumano
mesh_terms: D000818:Animals; D000943:Antigens, Differentiation / Q000032:analysis; D002454:Cell Differentiation; D019070:Cell Lineage; D002465:Cell Movement; D002469:Cell Separation; D004268:DNA-Binding Proteins; D005434:Flow Cytometry; D015329:Gene Rearrangement, T-Lymphocyte; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000737:chemistry / Q000166:cytology*; D006413:Hematopoietic System / Q000196:embryology*; D016130:Immunophenotyping; D053631:Interleukin Receptor Common gamma Subunit; D007694:Killer Cells, Natural / Q000166:cytology*; D017493:Leukocyte Common Antigens / Q000032:analysis; D008099:Liver / Q000166:cytology / Q000196:embryology*; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008819:Mice, Nude; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D020395:Receptors, Interleukin-7 / Q000172:deficiency / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016176:T-Lymphocyte Subsets / Q000166:cytology*
chemical_list: D000943:Antigens, Differentiation; D004268:DNA-Binding Proteins; C507942:Il2rg protein, mouse; D053631:Interleukin Receptor Common gamma Subunit; C499308:Rag2 protein, mouse; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D020395:Receptors, Interleukin-7; C064655:V(D)J recombination activating protein 2; D017493:Leukocyte Common Antigens