Fetal hematopoietic stem cells express MFG-E8 during mouse embryogenesis.
- Author:
Jaehun LEE
1
;
Byung Il CHOI
;
Seo Young PARK
;
Su Yeon AN
;
Jiyou HAN
;
Jong Hoon KIM
Author Information
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- MeSH: Animals; Antigens, CD34/analysis; Antigens, Surface/*analysis; Bone Marrow/ultrastructure; Female; Hematopoietic Stem Cells/*cytology; Liver/embryology; Mice/*embryology; Milk Proteins/*analysis; Placentation; Pregnancy
- From:Experimental & Molecular Medicine 2015;47(7):e174-
- CountryRepublic of Korea
- Language:English
- Abstract: The milk fat globule-EGF-factor 8 protein (MFG-E8) has been identified in various tissues, where it has an important role in intercellular interactions, cellular migration, and neovascularization. Previous studies showed that MFG-E8 is expressed in different cell types under normal and pathophysiological conditions, but its expression in hematopoietic stem cells (HSCs) during hematopoiesis has not been reported. In the present study, we investigated MFG-E8 expression in multiple hematopoietic tissues at different stages of mouse embryogenesis. Using immunohistochemistry, we showed that MFG-E8 was specifically expressed in CD34+ HSCs at all hematopoietic sites, including the yolk sac, aorta-gonad-mesonephros region, placenta and fetal liver, during embryogenesis. Fluorescence-activated cell sorting and polymerase chain reaction analyses demonstrated that CD34+ cells, purified from the fetal liver, expressed additional HSC markers, c-Kit and Sca-1, and that these CD34+ cells, but not CD34- cells, highly expressed MFG-E8. We also found that MFG-E8 was not expressed in HSCs in adult mouse bone marrow, and that its expression was confined to F4/80+ macrophages. Together, this study demonstrates, for the first time, that MFG-8 is expressed in fetal HSC populations, and that MFG-E8 may have a role in embryonic hematopoiesis.
