| First Author | Mise-Omata S | Year | 2014 |
| Journal | Int Immunol | Volume | 26 |
| Issue | 11 | Pages | 607-18 |
| PubMed ID | 24908679 | Mgi Jnum | J:260562 |
| Mgi Id | MGI:6147989 | Doi | 10.1093/intimm/dxu062 |
| Citation | Mise-Omata S, et al. (2014) NF-kappaB RELA-deficient bone marrow macrophages fail to support bone formation and to maintain the hematopoietic niche after lethal irradiation and stem cell transplantation. Int Immunol 26(11):607-18 |
| abstractText | Bone remodeling and hematopoiesis are interrelated and bone marrow (BM) macrophages are considered to be important for both bone remodeling and maintenance of the hematopoietic niche. We found that NF-kappaB Rela-deficient chimeric mice, generated by transplanting Rela (-/-) fetal liver cells into lethally irradiated hosts, developed severe osteopenia, reduced lymphopoiesis and enhanced mobilization of hematopoietic stem and progenitor cells when BM cells were completely substituted by Rela-deficient cells. Rela (-/-) hematopoietic stem cells from fetal liver had normal hematopoietic ability, but those harvested from the BM of osteopenic Rela (-/-) chimeric mice had reduced repopulation ability, indicating impairment of the microenvironment for the hematopoietic niche. Osteopenia in Rela (-/-) chimeric mice was due to reduced bone formation, even though osteoblasts differentiated from host cells. This finding indicates impaired functional coupling between osteoblasts and hematopoietic stem cell-derived cells. Rela-deficient BM macrophages exhibited an aberrant inflammatory phenotype, and transplantation with wild-type F4/80(+) BM macrophages recovered bone formation and ameliorated lymphopoiesis in Rela (-/-) chimeric mice. Therefore, RELA in F4/80(+) macrophages is important both for bone homeostasis and for maintaining the hematopoietic niche after lethal irradiation and hematopoietic stem cell transplantation. |
