title: Two waves of distinct hematopoietic progenitor cells colonize the fetal thymus.
abstract: The generation of T cells depends on the migration of hematopoietic progenitor cells to the thymus throughout life. The identity of the thymus-settling progenitor cells has been a matter of considerable debate. Here we found that thymopoiesis was initiated by a first wave of T cell lineage-restricted progenitor cells with limited capacity for population expansion but accelerated differentiation into mature T cells. They gave rise to αβ and γδ T cells that constituted Vγ3(+) dendritic epithelial T cells. Thymopoiesis was subsequently maintained by less-differentiated progenitor cells that retained the potential to develop into B cells and myeloid cells. In that second wave, which started before birth, progenitor cells had high proliferative capacity but delayed differentiation capacity and no longer gave rise to embryonic γδ T cells. Our work reconciles conflicting hypotheses on the nature of thymus-settling progenitor cells.
authors: 1] Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France. [2] Université Pierre et Marie Curie, Paris, France. [3].
authors: Cyrille
authors: C
authors: Ramond
authors: 1] Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France. [2] Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France. [3].
authors: Claire
authors: C
authors: Berthault
authors: 1] Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France. [2].
authors: Odile
authors: O
authors: Burlen-Defranoux
authors: Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France.
authors: Ana Pereira
authors: AP
authors: de Sousa
authors: Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France.
authors: Delphine
authors: D
authors: Guy-Grand
authors: Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France.
authors: Paulo
authors: P
authors: Vieira
authors: Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France.
authors: Pablo
authors: P
authors: Pereira
authors: Unit for Lymphopoiesis, Immunology Department, INSERM U668 Paris, France.
authors: Ana
authors: A
authors: Cumano
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002454:Cell Differentiation / Q000235:genetics*; D002460:Cell Line; D019070:Cell Lineage / Q000235:genetics; D002478:Cells, Cultured; D005434:Flow Cytometry; D018507:Gene Expression Regulation, Developmental; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism*; D053699:Interleukin-7 Receptor alpha Subunit / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D020411:Oligonucleotide Array Sequence Analysis; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000235:genetics / Q000378:metabolism; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000166:cytology / Q000378:metabolism*; D060168:Thymocytes / Q000166:cytology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology / Q000196:embryology / Q000378:metabolism*; D013997:Time Factors; D059467:Transcriptome; D051941:fms-Like Tyrosine Kinase 3 / Q000235:genetics / Q000378:metabolism
chemical_list: D053699:Interleukin-7 Receptor alpha Subunit; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016692:Receptors, Antigen, T-Cell, gamma-delta; D051941:fms-Like Tyrosine Kinase 3