Figure 4 | Scientific Reports

Figure 4

From: The serine proteinase hepsin is an activator of pro-matrix metalloproteinases: molecular mechanisms and implications for extracellular matrix turnover

Figure 4

Hepsin expression is associated with inflammation. (A) Bovine articular cartilage was excised from metacarpophalangeal joints and stimulated with IL-1 (5 ng/ml) and OSM (10 ng/ml) for 4 days. RNA was isolated and reverse transcribed prior to real-time PCR. Data were normalized to the level of 18 S rRNA and plotted as mean ± SD fold change (n = 4). Significant differences were determined using a t-test where ***p < 0.001. (B) Gene expression levels in hip synovium from patients with OA (closed circles; n = 12) or normal controls (NOF) (open squares; n = 12) of HPN were determined as described in the Experimental procedures and normalized to the level of glyceraldehyde 3-phosphate dehydrogenase (GAPDH). HPN expression was undetected in 8/12 NOF samples and 2/12 OA samples, and significant differences between the normal and OA groups were determined using a two-sided Mann-Whitney U test, where **p < 0.01. (C) Human OA synovia samples were fixed, embedded in paraffin, sectioned and stained with haematoxylin and eosin. Synovitis was scored blinded by two independent scorers based on levels of inflammation, stromal activation and hyperplasia. Summed scores were totaled and described as no synovitis (0–1), slight synovitis (2–3), and moderate synovitis (4–6). Representative samples from within this scoring scale are presented where hepsin was detected by immunohistochemistry using a rabbit anti-hepsin polyclonal antibody. A control consisting of no primary antibody (NPA) was also performed. The scale bars represent 100 µm (except 50 µm for the insets).