Fig. 1
From: Protease inhibitors enhance extracellular collagen fibril deposition in human mesenchymal stem cells
Collagen internalization and degradation by hMSCs (P6). a-f Two-dimensional monolayer culture: a-c 1-hour incubation in serum-free medium (green: Alexa Fluor 488 labeled collagen; 25 μg/ml; blue: nucleus labeled by DAPI); d-f 24-hour incubation in serum-free medium where DQ FITC-labeled collagen was 10 % of total collagen content (20 μg/ml) (green: fluorescein-conjugated DQ-collagen type I; red: lysosomes). g-i Three-dimensional culture in collagen microspheres at different time points: g 2 mg/ml type I rat collagen with cell density at 1 × 105 per ml at 3 h after encapsulation; h 1 mg/ml type I rat collagen with cell density at 5 × 105 per ml at 19 h after encapsulation; i 1 mg/ml type I rat collagen with cell density at 5 × 105 per ml at 23 h after encapsulation; i1 and i2 Side views of hMSCs inside a collagen microsphere (green: 1 % fluorescein-labeled bovine collagen; red: LysoTracker-labeled cell). DAPI 4ʹ,6-diamidino-2-phenylindole, FITC fluorescein isothiocyanate, hMSC human mesenchymal stem cell