Fig. 4
From: Protease inhibitors enhance extracellular collagen fibril deposition in human mesenchymal stem cells
Collagen fibril deposition by hMSCs with and without exogenously supplemented collagen or ascorbic acid or both. a-d Immunofluorescence staining of exogenous type I collagen (rat) and newly synthesized type I collagen (human) in hMSCs without ascorbic acid but with exogenously supplemented collagen: a Merged channels. b Rat type I collagen. c Human type I collagen. d Nuclei. e-h Immunofluorescence staining of collagen type I in hMSCs with ascorbic acid but without exogenously supplemented collagen. i-l Immunofluorescence staining of human type I collagen and fluorescence-labeled exogenous rat type I collagen when vitamin C and exogenous collagen were co-supplemented. e, i Control. f, j Intracellular protease inhibitor E64D. g, k Combination of intracellular (E64D) and extracellular (GM6001) protease inhibitors. h, l Extracellular protease inhibitor GM6001. For (e-l), green: human type I collagen; red: Exogenously supplemented fluorescence-labeled rat tail collagen type I; blue: 4ʹ,6-diamidino-2-phenylindole (DAPI). hMSC human mesenchymal stem cell