The relationship between stem cell seeding efficiency and position in cell cycle.

The seeding efficiency of colony-forming cells from normal, regenerating and velocity-sedimented cycling and non-cycling narrow preparations was compared. Colony-forming cells in cycle were found to exhibit a 50% reduction in splenic seeding when compared to normal marrow or sedimented non-cycling cells. The results of this study indicate that the spleen colony assay underestimates the total number of colony-forming cells by a fraction which is directly related to the number of cells in cycle.