The first 3 days of B-cell development in the mouse embryo.
B-lineage-committed cells are believed to arise in the liver of mouse embryos at 14 days after coitus (dpc). However, pre-B-specific gene transcripts and DJH gene rearrangements have been detected in earlier, midgestation embryos. We describe here a population of c-kit(+)AA4.1(+)CD19(+)Pax5(+) cells present in the aorta-gonad-mesonephros (AGM) area and in the livers of 11-dpc mouse embryos. In contrast to multipotent c-kit(+)AA4.1(+)CD19(-) hematopoietic stem cells (HSCs), these c-kit(+)AA4.1(+)CD19(+) progenitors differentiated only to B-lineage cells in vitro. We propose that mouse embryonic B lymphopoiesis starts earlier than previously thought, at 10 to 11 dpc, both in liver and extra-liver hematopoietic sites. The B-cell differentiation program is not delayed with respect to the emerging lymphohematopoiesis events in the midgestation mouse embryo (8-9 dpc).
de Andrés
Belen
B
Centro Nacional de Microbiologia, Instituto de Salud Carlos III (ISCIII), Majadahonda, Spain.
Gonzalo
Pilar
P
Minguet
Susana
S
Martínez-Marin
José A
JA
Soro
Pilar G
PG
Marcos
Miguel Angel R
MA
Gaspar
María Luisa
ML
D000818:Animals; D018941:Antigens, CD19 / Q000502:physiology; D001011:Aorta / Q000166:cytology / Q000196:embryology / Q000276:immunology; D001402:B-Lymphocytes / Q000166:cytology*; D002454:Cell Differentiation; D019070:Cell Lineage; D006066:Gonads / Q000166:cytology / Q000196:embryology / Q000276:immunology; D006412:Hematopoietic Stem Cells / Q000166:cytology; D008099:Liver / Q000166:cytology / Q000196:embryology / Q000276:immunology; D038041:Lymphopoiesis / Q000235:genetics / Q000276:immunology; D008650:Mesonephros / Q000166:cytology / Q000196:embryology / Q000276:immunology; D051379:Mice / Q000196:embryology*; D008807:Mice, Inbred BALB C; D013997:Time Factors
D018941:Antigens, CD19