Hemopoiesis on purified bone-marrow-derived reticular fibroblast in vitro.
Murine bone-marrow-derived reticular fibroblast cultures were tested for the ability to support hemopoiesis and release hemopoietic growth factors in vitro. The reticular fibroblast cultures employed in these studies were 95%-100% pure on the basis of Mac-1, F4/80, MIV-51, T200, antifactor VIII and ER-TR7 monoclonal antibody staining. Further support for the fibroblastic nature of these cells was obtained from collagen and laminin analyses. Addition of stromal cell-depleted bone marrow cell suspensions to flasks of confluent reticular fibroblasts resulted in production and release of granulocytes, monocyte-macrophages, and granulocyte-monocyte progenitors from the adherent layer for 4-8 weeks. Pluripotent spleen colony-forming units were detected during the first four weeks. Assay of reticular fibroblast conditioned medium for hemopoietic growth factors demonstrated production of granulocyte-macrophage colony-stimulating activity and stem-cell-activating factor. We did not detect any erythroid burst-promoting activity. These results suggest that reticular fibroblasts may play a role in the maintenance of pluripotent stem cells and in the proliferation and differentiation of cells committed to the granulocyte-monocyte lineage.
Brockbank
K G
KG
de Jong
J P
JP
Piersma
A H
AH
Voerman
J S
JS
D000818:Animals; D001854:Bone Marrow Cells; D002454:Cell Differentiation; D002455:Cell Division; D002478:Cells, Cultured; D005260:Female; D005347:Fibroblasts / Q000502:physiology*; D006098:Granulocytes / Q000166:cytology; D006410:Hematopoiesis; D008264:Macrophages / Q000166:cytology; D008297:Male; D051379:Mice; D009000:Monocytes / Q000166:cytology