LPS from P. gingivalis and Hypoxia Increases Oxidative Stress in Periodontal Ligament Fibroblasts and Contributes to Periodontitis

Figure 6

Superoxide dismutase (SOD) occurrence in healthy and inflamed human tissue. Healthy gingival epithelium (a), periodontal ligament (b), and samples of gingivitis (c) or periodontitis (d) were obtained after the approval of the Ethics Committee of the University of Bonn and parental as well as patient’s allowance (). Polyclonal primary antibody against SOD (Abcam, Cambridge, UK) was used in a concentration of 1 : 100. Gingival epithelium showed a moderate to strong staining of SOD in keratinocytes which was primarily limited to the cytosol (Figure 6(a) and red arrow depicts the typical localization). In the healthy periodontium, gingival and PDL fibroblasts were weakly stained (Figure 6(b)). In inflamed tissues, basal epithelial cells seemed to be stained more intensively in the gingivitis specimen than in periodontitis (Figures 6(c) and 6(d)). In addition, the subepithelium revealed immunoreactivity in local cells like gingival fibroblasts and scattered immune cells (Figure 6(c), see red arrow). In periodontitis, SOD immunostaining seemed to be limited to the gingival epithelium (Figure 6(d); see red arrow). The scale bars indicate 200 μm in the surveys and 50 μm in the higher magnifications, respectively.

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