title: Quantitation of stromal and hemopoietic progenitors in spleen and femoral marrow derived from Steel (Slj/+ and Sl/Sld) mice and their normal littermates.
abstract: In vitro analyses of stromal fibroblast colony-forming units (CFUF) and hemopoietic progenitors (erythroid burst-forming units, BFUE; granulocyte/macrophage colony-forming units, CFUGM) in hemopoietic organs of 'Steel' (Slj/+ and Sl/Sld) mice and their hematologically normal littermates were performed. CFUF incidence was not significantly different from +/+ controls in hemopoietic organs from either 'Steel' allele. There was, however, a tendency for the CFUF content to be above normal in 'Steel' spleens. BFUE incidence and absolute numbers were found to be significantly reduced in both Sl/Sld and Slj/+ spleens. We confirm previous reports of a reduced femoral BFUE content and reduced splenic and femoral CFUGM content in Sl/Sld mice. The total body content of BFUE and CFUGM was 21 and 50 percent of +/+ littermates, respectively, in Sl/Sld mice and 68 and 64 percent in Slj/+ mice. These results indicate that the microenvironmental defect in Slj/+ and Sl/Sld mice a) involves hemopoietic progenitors committed to both the erythrocytic and granulocyte/macrophage differentiation pathways; b) is greater in spleen than in femoral marrow; and c) cannot be explained by a deficiency in stromal progenitor content of the hemopoietic organs.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D003114:Colony-Forming Units Assay; D004912:Erythrocytes / Q000276:immunology; D005269:Femur; D005347:Fibroblasts / Q000276:immunology; D006410:Hematopoiesis; D006412:Hematopoietic Stem Cells / Q000276:immunology; D051379:Mice; D008817:Mice, Mutant Strains / Q000097:blood*; D013154:Spleen / Q000166:cytology