Fig. 1

a Total glycosaminoglycan (GAG) production per pellet for each MSC preparation and ACP clone indicated variation among human donors. A threshold (dashed line) defined as two standard deviations from the total GAG production during pellet chondrogenesis for healthy human chondrocytes was set for each cell type, and low-GAG and high-GAG groups were categorized. b Mean (± SD) fold-change GAG production in physioxia relative to hyperoxia was significant for all groups other than high-GAG ACPs, and a significant difference existed between the fold-change for low-GAG and high-GAG groups of each cell type. c Mean (± SD) fold-change DNA content in physioxia relative to hyperoxia was no different between oxygen level, GAG level, nor cell type. Statistical significance defined as *p < 0.05, ***p < 0.001. ACP articular cartilage progenitor, MSC mesenchymal stem cell