title: Dissimilarity of in vitro colon-forming cells and erythrocyte-enhanced colony-forming cells from mouse marrow.
abstract: In vitro colony-forming cells (CFU-C's) differed from erythrocyte-enhanced colony-forming cells (EE-CFU-C's) in their liquid culture kinetics, adherence properties, and sedimentation velocities. Murine marrow cells stimulated with colony-stimulating activity (CSA) were grown in liquid culture in the presence or absence of washed erythrocytes. A seven to eightfold increase in the number of CFU-C's occurred on day 2 of culture. A somewhat greater increase of nine to 11-fold was observed for EE-CFU-C's which reached a maximum on day 4. When CSA was omitted from the liquid cultures, no increase in CFU-C's or EE-CFU-C's was observed. Marrow cell separation by glass bead adherence columns disclosed a greater degree of adherence for the EE-CFU-C population. Nonadherent cell fractions exhibited a decreased EE-CFU-C/CFU-C ratio (1.19 to 1.24) when compared to controls (3.33) whereas an increase was observed for the eluted, adherent cell population (5.06-6.02). Velocity sedimentation experiments demonstrated a size difference for the marrow-derived CFU-C and EE-CFU-C. CFU-C's sedimented with a velocity of 4.5 mm./hour and EE-CFU-C's sedimented at the rate of 5.7 mm./hour. These observations indicate that EE-CFU-C's appear to represent a population of cells different from the CFU-C's. The later time of peak appearance of EE-CFU-C's in liquid culture suggests that the EE-CFU-C may be a progeny of the CFU-C.
mesh_terms: D000818:Animals; D001854:Bone Marrow Cells; D002448:Cell Adhesion; D002455:Cell Division; D002478:Cells, Cultured; D002999:Clone Cells; D004912:Erythrocytes; D006410:Hematopoiesis; D007700:Kinetics; D051379:Mice