title: Characterization of hemangioblast in umbilical arteries of mid-gestation mouse embryos.
abstract: Hemangioblasts are the common precursors of hematopoietic and vascular cells, and are characterized as blast colony-forming cells (BL-CFCs) in vitro. We previously identified BL-CFCs in the mouse aorta-gonads-mesonephros (AGM) region, but not yolk sac, placenta, circulation, or fetal liver. Here, we aim to determine whether BL-CFCs develop in the umbilical arteries (UA) that link the dorsal aorta (sub-region of AGM) and placenta. We find that the UA cells of E11.5 mouse embryos were capable of generating typical blast colonies. On replating, these colonies produced erythroid/myeloid progenitors and B220(+) B lymphocytes in vitro, corroborating their definitive hematopoietic nature. They also generated CD31(+) or endomucin(+) tube-like structures on OP9 stromal cells, showing their endothelial potential. The proximal and distal regions of UA had equal numbers of BL-CFCs. To evaluate whether BL-CFCs can be autonomously maintained or expanded in UA or AGM, in vitro organ culture was performed. Interestingly, the BL-CFC pool in the AGM was significantly amplified, in striking contrast to a decrease in the UA. Taken together, our findings indicate that in addition to the AGM the UA serves as an important, but less supportive, niche for hemangioblast development.
authors.affiliation: Department of Cardiology, Xinqiao Hospital, Third Military Medical University, Chongqing 400038, China.
authors.forename: Weixi
authors.initials: W
authors.lastname: Niu
authors.forename: He
authors.initials: H
authors.lastname: Huang
authors.forename: Liangyu
authors.initials: L
authors.lastname: Zhao
authors.forename: Zhuan
authors.initials: Z
authors.lastname: Li
authors.forename: Wenyan
authors.initials: W
authors.lastname: He
authors.forename: Bing
authors.initials: B
authors.lastname: Liu
authors.forename: Longgui
authors.initials: L
authors.lastname: Li
authors.forename: Jiaxiang
authors.initials: J
authors.lastname: Xiong
mesh_terms: D000818:Animals; D003114:Colony-Forming Units Assay; D005865:Gestational Age; D055018:Hemangioblasts / Q000166:cytology* / Q000378:metabolism; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000378:metabolism; D016130:Immunophenotyping; D051379:Mice; D008810:Mice, Inbred C57BL; D009924:Organ Culture Techniques; D014469:Umbilical Arteries / Q000166:cytology* / Q000196:embryology*