Description
We induced mouse embryonic stem cells (ESCs) into B progenitors in in vitro culture. We previously reported that B cells derived from extra-embryonic yolks sac (YS) belong to innate-like B-1 cells, not conventional B-2 cells. Since ES cell differentiation into Blood lineage, it recapitulates YS hematopoiesis, we hypothesized that B cells produced by mouse ESCs belong to B-1 cells as well. We transplanted ESC-derived B-progenitor cells into immunodeficient mice and confirmed that ES-derived B cells differentiate into only B-1 and marginal zone B cells, not B-2 cells in vivo. We preformed gene expression profiles by RNA sequencing comparing ESC-derived, YS-derived, fetal liver derived, and adult bone marrow derived B progenitor cells to see their characteristics. Overall design: We compared gene expression profllings among B-1 progeniotors derived from ES, Yolk sac, and fetal liver, and B-2 progenitors from adult bone marrow. We isolated CD19+B220+ B-progenitor cells obtained from in vitro culture of mouse ES cells, yolk sac, and fetal liver (all B-1 biased) and bone marrow (B-2 biased) and performed RNA sequencing Please note that Flk1 is a marker of mesoderm that differentiate into endothelial cells and blood cells and VEcad (VE-cadherin) is a marker of endothelial cells. It is known that all hematopoietic cells are derived from lateral mesoderm (Flk1+) cells via endothelial phenotype (VE-cad+). Therefore, we differentiated ESCs into Flk1+ mesoderm or VEcad+ endothelial cells and isolated them by sorting (as indicated in the sample source name field), and replated them onto OP9-stromal cells that support B cell development.