title: CD45(low)c-Kit(high) cells have hematopoietic properties in the mouse aorta-gonad-mesonephros region.
abstract: Long-term reconstituting hematopoietic stem cells first arise from the aorta of the aorta-gonad-mesonephros (AGM) region in a mouse embryo. We have previously reported that in cultures of the dispersed AGM region, CD45(low)c-Kit(+) cells possess the ability to reconstitute multilineage hematopoietic cells, but investigations are needed to show that this is not a cultured artifact and to clarify when and how this population is present. Based on the expression profile of CD45 and c-Kit in freshly dissociated AGM cells from embryonic day 9.5 (E9.5) to E12.5 and aorta cells in the AGM from E13.5 to E15.5, we defined six cell populations (CD45(-)c-Kit(-), CD45(-)c-Kit(low), CD45(-)c-Kit(high), CD45(low)c-Kit(high), CD45(high)c-Kit(high), and CD45(high)c-Kit(very low)). Among these six populations, CD45(low)c-Kit(high) cells were most able to form hematopoietic cell colonies, but their ability decreased after E11.5 and was undetectable at E13.5 and later. The CD45(low)c-Kit(high) cells showed multipotency in vitro. We demonstrated further enrichment of hematopoietic activity in the Hoechst dye-effluxing side population among the CD45(low)c-Kit(high) cells. Here, we determined that CD45(low)c-Kit(high) cells arise from the lateral plate mesoderm using embryonic stem cell-derived differentiation system. In conclusion, CD45(low)c-Kit(high) cells are the major hematopoietic cells of mouse AGM.
authors.affiliation: Department of Stem Cell Regulation, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan. nobuhisa.scr@mri.tmd.ac.jp
authors.forename: Ikuo
authors.initials: I
authors.lastname: Nobuhisa
authors.forename: Shoutarou
authors.initials: S
authors.lastname: Yamasaki
authors.forename: Ahmed
authors.initials: A
authors.lastname: Ramadan
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Taga
mesh_terms: D000818:Animals; D001011:Aorta / Q000166:cytology* / Q000196:embryology / Q000378:metabolism; D002454:Cell Differentiation; D006066:Gonads / Q000166:cytology* / Q000196:embryology / Q000378:metabolism; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D017493:Leukocyte Common Antigens / Q000378:metabolism*; D008650:Mesonephros / Q000166:cytology* / Q000196:embryology; D051379:Mice; D019009:Proto-Oncogene Proteins c-kit / Q000378:metabolism*
chemical_list: D019009:Proto-Oncogene Proteins c-kit; D017493:Leukocyte Common Antigens