(a): Overlay of Cy3, Cy5 and DAPI filter sets. In some regions of the biofilm Filifactor rods can reach a considerable length. (b and c): Overlay of Cy3 and DAPI filter sets. (b) shows the radial orientation of F. alocis and other organisms BI 2536 on the surface of a mushroom-like protuberance of the biofilm. (c) shows F. alocis forming test-tube-brush-like structures around a signal-free channel. (d): Overlay of Cy3 and Cy5 filter sets. F. alocis and fusiform bacteria form concentrical structures. Similar formations that indicate ultrastructural organisation of the biofilm could be observed in the gingival biopsy. In several areas, F. alocis formed branch-like structures within the affected tissue

(EX 527 purchase Figure 6a) or palisades around large rodshaped bacteria (Figure 6b). Again, Filifactor was observed among the organisms in concentric bacterial aggregations (Figure 6c). Figure 6 LCZ696 cost Formations of F. alocis in periodontal tissue. FISH on a biopsy gained during periodontal surgery using the probes EUB 338-Cy5 (magenta) and FIAL-Cy3 (bright orange) along with DAPI staining (blue). EUB 338 visualizes the entire bacterial community, while FIAL detects only F. alocis.

DAPI stains both host cell nuclei and bacteria. High magnifications depict F. alocis in different parts of the biopsy. (a): F. alocis forms tree-like structures among coccoid and fusiform bacteria and autofluorescent ASK1 erythrocytes. (b) shows F. alocis forming palisades with fusiform bacteria around large rodshaped eubacterial organisms. (c) shows F. alocis being part of concentrical bacterial aggregations resembling those detected in GAP carriers. Discussion To our knowledge, the present study is the first to analyse the prevalence

of F. alocis in samples from both GAP and CP patients, and subjects with apparent periodontitis resistance. The detection of the organism in 77.8% of the GAP patients and in 76.7% of those suffering from CP is convincing evidence that suggests an involvement of F. alocis in periodontal disease. Equally striking is the low prevalence of Filifactor in the PR group. All of these patients had reached the age of 65 years and were in good periodontal condition without the help of extensive therapeutic efforts. Even if a multitude of factors including oral hygiene and immune response contributed to their periodontal status, one would assume that frequent detection of an organism in the GAP and CP groups along with scarce detection in PR patients, as is the case for F. alocis, indicates pathogenic rather than commensal behaviour. One can argue that deep periodontal pockets harbour increased numbers of bacteria and that any organism inevitably should be isolated more constantly from CP patients (mean pocket depth: 7.13 mm, 1.4 mm SD) and especially GAP patients (7.81 mm, 2.48 mm SD) than from PR patients (3.63 mm, 0.79 mm SD).