ESAM
Endothelial cell-selective adhesion molecule precursor [UNQ220/PRO246]
Publications[править]
Although recent advances have enabled hematopoietic stem cells (HSCs) to be enriched to near purity, more information about their characteristics will improve our understanding of their development and stage-related functions. Here, using microarray technology, we identified endothelial cell-selective adhesion molecule (ESAM) as a novel marker for murine HSCs in fetal liver. Esam was expressed at high levels within a Rag1(-) c-kit(Hi) Sca1( ) HSC-enriched fraction, but sharply down-regulated with activation of the Rag1 locus, a valid marker for the most primitive lymphoid progenitors in E14.5 liver. The HSC-enriched fraction could be subdivided into 2 on the basis of ESAM levels. Among endothelial antigens on hematopoietic progenitors, ESAM expression showed intimate correlation with HSC activity. The ESAM(Hi) population was highly enriched for multipotent myeloid-erythroid progenitors and primitive progenitors with lymphopoietic activity, and exclusively reconstituted long-term lymphohematopoiesis in lethally irradiated recipients. Tie2( ) c-kit( ) lymphohematopoietic cells in the E9.5-10.5 aorta-gonad-mesonephros region also expressed high levels of ESAM. Furthermore, ESAM was detected on primitive hematopoietic progenitors in adult bone marrow. Interestingly, ESAM expression in the HSC-enriched fraction was up-regulated in aged mice. We conclude that ESAM marks HSC in murine fetal liver and will facilitate studies of hematopoiesis throughout life.
MeSH Terms
- Aging
- Animals
- Biomarkers
- Cell Adhesion Molecules
- Cells, Cultured
- Embryo, Mammalian
- Endothelial Cells
- Female
- Fetus
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Gene Knock-In Techniques
- Hematopoiesis
- Hematopoietic Stem Cells
- Liver
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Oligonucleotide Array Sequence Analysis