Figure 5.

Lysyl oxidase (LOX) promotes extracellular matrix production ex vivo in human skin tissues. A: human skin tissues from healthy donors were treated with recombinant LOX (LOX) or vehicle (VC) for 120 h. Representative H&E images of human skin tissues treated with LOX and VC. Scale bar, 40 µm. B: the thickness of skin tissues was measured from H&E stained sections. The data were obtained from four different experiments using skin tissues of four different individual normal donors. Values represent means ± SD. Graphical presentation of the data analyzed by unpaired t test. ***P < 0.001. C: mRNA levels of collagen 1A1 (Col1A1) and collagen 1A2 (Col1A2) were measured in skin tissues treated with VC or LOX for 48 h. The data were obtained from 11 different experiments using skin tissues of 11 different individual normal donors. Graphical presentation of the data analyzed by paired t test. Values represent means ± SD. *P < 0.05. **P < 0.01. D: the amount of collagen in the skin tissues was evaluated by hydroxyproline assay. Total collagen was expressed as μg collagen per 3-mm skin punch. The data were obtained from six different experiments using skin tissues of six different individual normal donors. Graphical presentation of the data analyzed by unpaired t test. Values represent means ± SD. **P < 0.01. E: dermal fibroblasts were cultured from the skin of patients with systemic sclerosis (SSc) and their healthy twins as controls (HC). LOX mRNA levels were measured using qPCR in passage 3 fibroblasts. The data were obtained from dermal fibroblasts of 17 different patients with SSc and their healthy twins. Graphical presentation of the data analyzed by paired t test. Values represent means ± SD. *P < 0.05.