Endothelial protein C receptor (EPCR) has been established as a marker specifically distinguishing hematopoietic stem cells (HSC) that reside in murine bone marrow. In contrast, HSC released into the peripheral blood circulation do not express EPCR. We questioned whether the use of EPCR could be extended to identifying tissue-resident HSC in extramedullary organs. Murine spleen is known to harbour HSC from neonatal to adult stages. As an organ that functions explicitly in blood filtration, it has been uncertain whether these cells represent transitory or endogenous HSC. Studies using parabiosis have now clarified that a large proportion of spleen HSC are in fact endogenous to the tissue. We now make a direct comparison of adult spleen, peripheral blood, and bone marrow HSC, to determine the percentage of EPCR+, and thus tissue-resident HSC, in spleen. Our results confirm that spleen indeed contains a high percentage of EPCR+ HSC comparable to bone marrow. We also extend our investigation to examine whether several modes of extramedullary hematopoiesis lead to an expansion of spleen-resident EPCR+ HSC, or an influx of HSC mobilised into the circulation from bone marrow.
|Published - 3 Jun 2016
|European Molecular Biology Laboratory Conference Hematopoietic Stem Cells: From the Embryo to the Aging Organism - European Molecular Biology Laboratory, Heidelberg, Germany
Duration: 3 Jun 2016 → 5 Jun 2016
|European Molecular Biology Laboratory Conference Hematopoietic Stem Cells
|3/06/16 → 5/06/16