title: Single-cell analysis of early B-lymphocyte development suggests independent regulation of lineage specification and commitment in vivo.
abstract: To better understand the process of B-lymphocyte lineage restriction, we have investigated molecular and functional properties in early B-lineage cells from Pax-5-deficient animals crossed to a B-lineage-restricted reporter mouse, allowing us to identify B-lineage-specified progenitors independently of conventional surface markers. Pax-5 deficiency resulted in a dramatic increase in the frequency of specified progenitor B-cells marked by expression of a λ5 (Igll1) promoter-controlled reporter gene. Gene expression analysis of ex vivo isolated progenitor cells revealed that Pax-5 deficiency has a minor impact on B-cell specification. However, single-cell in vitro differentiation analysis of ex vivo isolated cells revealed that specified B-lineage progenitors still displayed a high degree of plasticity for development into NK or T lineage cells. In contrast, we were unable to detect any major changes in myeloid lineage potential in specified Pax-5-deficient cells. By comparison of gene expression patterns in ex vivo isolated Pax-5- and Ebf-1-deficient progenitors, it was possible to identify a set of B-cell-restricted genes dependent on Ebf-1 but not Pax-5, supporting the idea that B-cell specification and commitment is controlled by distinct regulatory networks.
authors.affiliation: Department of Clinical and Experimental Medicine, Faculty for Health Sciences, Linköping University, 58285 Linköping, Sweden.
authors.forename: Sasan
authors.initials: S
authors.lastname: Zandi
authors.forename: Josefine
authors.initials: J
authors.lastname: Ahsberg
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Tsapogas
authors.forename: Jenny
authors.initials: J
authors.lastname: Stjernberg
authors.forename: Hong
authors.initials: H
authors.lastname: Qian
authors.forename: Mikael
authors.initials: M
authors.lastname: Sigvardsson
mesh_terms: D000818:Animals; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology*; D002454:Cell Differentiation / Q000502:physiology*; D005786:Gene Expression Regulation / Q000276:immunology*; D006801:Humans; D007694:Killer Cells, Natural / Q000166:cytology / Q000276:immunology; D051379:Mice; D008822:Mice, Transgenic; D051757:PAX5 Transcription Factor / Q000235:genetics / Q000276:immunology; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology; D015534:Trans-Activators / Q000235:genetics / Q000276:immunology
chemical_list: C489921:Ebf1 protein, mouse; D051757:PAX5 Transcription Factor; C497282:Pax5 protein, mouse; D015534:Trans-Activators