Table 1.
Overview of the eight different experimental groups, which were tested in the study.
Table 2.
Self-designed forward primers, reverse primers and probes used for real-time PCR.
The primers and probes were designed and validated within our group using the primer express design software V.1.5 and were synthesized by Microsynth.
Fig 1.
BMP-2 concentration within the cell culture medium for control samples (red) and loaded samples (blue).
The BMP-2 concentration was determined using a quantitative ELISA for human BMP-2. The results are displayed as average ± standard deviation (n = 12). *Significant difference from the 3 day pre-culture time-point; # = loaded sample significantly different from day 1–7 time point; $ = significant difference in the unloaded vs. the loaded group, (p ≤ 0.05).
Fig 2.
TGF-β1 concentration within the cell culture medium.
The TGF-β1 concentration was determined using a quantitative ELISA for human TGF-β1. The results are displayed as average ± standard deviation (n = 12). # = significant difference between the control and the BMP-2 group (both loaded and unloaded); * = significant difference between control unloaded and control loaded; $ = significantly different from the 3 days pre-culture time-point, (p ≤ 0.05).
Fig 3.
Relative gene expression of hACPCs.
Gene expression analyses (a. Runx2, b. SOX9. c. Aggrecan, d. collagen I, e. collagen X, f. ALP) were conducted using the comparative ΔΔCT method and 18s RNA as internal control. * = significant difference between control and BMP-2 (comparing unloaded to unloaded and loaded to loaded); # = significant difference between unloaded and loaded; $ = significant difference between control unloaded and BMP-2 loaded, (p ≤ 0.05).
Table 3.
Overview of Col II gene expression within the study.
The table displays the groups, in which Col II message was detected within the four runs of the experiment. ND = not detectable.
Fig 4.
Relative gene expression of hACPCs.
Gene expression analyses (a. Notch 1, b. PTHrP, c. BMP-2) were conducted using the comparative ΔΔCT method and 18s RNA as internal control. * = Significant difference between control and BMP-2 (comparing unloaded to unloaded and loaded to loaded); # = significant difference between unloaded and loaded; $ = significant difference between control unloaded and BMP-2 loaded, (p ≤ 0.05).
Fig 5.
Total GAG (medium + scaffolds) production of hACPCs, seeded into fibrin-PU composite scaffolds, after 4 weeks of culture.
The GAG content was quantified using the DMMB dye binding assay with chondroitin-4-sulfate as standard. The results are displayed as average ± standard deviation (n = 12). * = Significantly different from the control loaded group, (p ≤ 0.05).
Fig 6.
GAG/DNA ratio of hACPCs, after 4 week of culture.
The total amount of GAG and the amount of DNA was quantified and GAG production was normalised to DNA content. Results are displayed as averages ± standard deviation (n = 12). * = significantly different from the control loaded group; $ = significantly different from the BMP-2 loaded group (p ≤ 0.05).