Fig. 2

ECM proteins produced by hADSCs, hBMSCs, and hCDPCs. The protein content and components of the cell sheets and dECM were determined by the BCA assay and SDS-PAGE. a. PicoGreen readouts of double-stranded DNA (dsDNA) amount of the cell sheets generated from different stem cells. b. hADSCs produced significantly higher amounts of protein than hBMSCs and hCDPCs. Group A: 3054.3 ± 196.3 μg/mL; group B: 1909.3 ± 221.9 μg/mL; group C: 2552.7 ± 37.9 μg/mL; ****p < 0.0001; ***p = 0.0005. Group dA, 321.0 ± 27.8 μg/mL; group dB, 278.5 ± 71.7 μg/mL; group dC, 381.8 ± 74.3 μg/mL; not significant between the dECM groups, p > 0.3. The experiment was repeated three times, with at least three technical replicates for each batch. One representative batch is shown, and the data are presented as mean ± SD. A two-way ANOVA, followed by LSD, was used for statistical analysis, and p < 0.05 was considered statistically significant. c. The BCA protein amount readouts of cell sheet and dECM groups, the cell sheet groups were normalized to PicoGreen dsDNA readouts, *p < 0.01; d. Diagram of the loading strategy used for SDS-PAGE. The samples were normalized to the protein concentration, and 5 μg protein was loaded into each lane of the gel. e. The SDS-PAGE results indicate the different ECM protein profiles (specifically at the ~ 10–20, 60, 75, 140, 230, and 260 kDa zones) of hADSCs, hBMSCs, and hCDPCs. The experiment was repeated at least three times, with at least two technical replicates for each trial. A representative trial is presented. A, cell sheet formed by hADSCs; dA, dECM from hADSC cell sheet; B, cell sheet formed by hBMSCs; dsDNA, double-stranded DNA; dB, dECM from hBMSC cell sheet; C, cell sheet formed by hCDPCs; dC, dECM from hCDPC cell sheet. hADSCs, human adipose-derived stem cells; hBMSCs, human bone marrow-derived stem cells; hCDPCs, human cartilage-derived progenitor cells; ECM, extracellular matrix; dECM, decellularized ECM; BCA, bicinchoninic acid, SD, standard deviation; ANOVA, analysis of variance; LSD, least significant difference; SDS-PAGE, sodium dodecyl sulfate–polyacrylamide gel electrophoresis. Figure 2d was created with BioRender.com by the authors with license obtained