| First Author | Sathyanarayana P | Year | 2007 |
| Journal | Blood | Volume | 110 |
| Issue | 2 | Pages | 509-18 |
| PubMed ID | 17403918 | Mgi Jnum | J:145402 |
| Mgi Id | MGI:3834521 | Doi | 10.1182/blood-2006-11-056465 |
| Citation | Sathyanarayana P, et al. (2007) Erythropoietin modulation of podocalyxin and a proposed erythroblast niche. Blood 110(2):509-18 |
| abstractText | Epo's erythropoietic capacity is ascribed largely to its antiapoptotic actions. In part via gene profiling of bone marrow erythroblasts, Epo is now shown to selectively down-modulate the adhesion/migration factors chemokine receptor-4 (Cxcr4) and integrin alpha-4 (Itga4) and to up-modulate growth differentiation factor-3 (Gdf3), oncostatin-M (OncoM), and podocalyxin like-1 (PODXL). For PODXL, Epo dose-dependent expression of this CD34-related sialomucin was discovered in Kit(+)CD71(high) proerythroblasts and was sustained at subsequent Kit(-)CD71(high) and Ter119(+) stages. In vivo, Epo markedly induced PODXL expression in these progenitors and in marrow-resident reticulocytes. This was further associated with a rapid release of PODXL(+) reticulocytes to blood. As studied in erythroblasts expressing minimal Epo receptor (EpoR) alleles, efficient PODXL induction proved dependence on an EpoR-PY343 Stat5 binding site. Moreover, in mice expressing an EpoR-HM F343 allele, compromised Epo-induced PODXL expression correlated with abnormal anucleated red cell representation in marrow. By modulating this select set of cell-surface adhesion molecules and chemokines, Epo is proposed to mobilize erythroblasts from a hypothesized stromal niche and possibly promote reticulocyte egress to blood. |
