intermedia (ATCC 25611), Campylobacter rectus (ATCC 33238), Capnocytophaga sputigena (ATCC 33612), Capnocytophaga gingivalis (ATCC 33624), Eggerthella lenta (ATCC 25559), and Peptostreptococcus anaerobius HSP inhibitor cancer (ATCC 27337). As none of the controls were detected by FIAL, all further experiments were performed with 20% (v/v) of formamide, including F. alocis as positive and F.

villosus as negative control. Epifluorescence microscopy After hybridization, carrier and biopsy sections were analysed using an epifluorescence microscope (AxioPlan II, Zeiss, Jena, Germany) equipped with a 100 W high pressure mercury lamp (HBO 103W/2, Osram, Munich, Germany) and 10×, 40× and 100× objectives. DAPI, Cy3 and Cy5 signals were analysed by narrow band filter sets HQ F31-000, HQ

F41-007 and HQ F41-008, respectively (AHF Analysentechnik, Tübingen, Germany). see more Image acquisition was performed with an AxioCam MRm (Zeiss) making use of the AxioVision 4.4 software. Results Dot blot hybridization When carried out with the probe EUB 338 (specific for most bacteria), dot blot hybridization experiments indicated the presence of bacteria in all 490 patient samples as well as in the positive (F. alocis) and negative controls (see Figure 1 legend) and thus confirmed successful PCR amplification (Figure 1a). The Filifactor alocis-specific probe FIAL clearly detected F. alocis, while neither the closest phylogenetic neighbour F. villosus nor any of the organisms in the panel of oral bacteria (see Figure 1 legend) yielded a signal, thus indicating specific hybridization conditions (Figure 1b). Taking all the collected samples into consideration, F. alocis could be identified in 77.8% of the 330 samples from 72 GAP patients, 76.7% of the 78 samples from 30 CP patients and 15.8% of the 82 samples from 19 PR patients (Table 2; Figure 2a). The prevalence of the organism was highest in the Oslo CP collective (87.5%), followed by the Basel GAP collective (80.0%), and the Dresden GAP collective (77.8%) (data not shown). As the number of samples per patient varied between the different

Urease collectives, statistical evaluation focused on the deepest pocket of each patient. Prevalence rates were 68.1% for the GAP group, 66.7% for the CP group and 5.3% for the PR group. While detection frequencies did not differ significantly between GAP and CP patients, both diseased groups harboured F. alocis significantly more often than the PR group (p < 0.001) (Figure 2b). Figure 2 Prevalence of F. alocis. (a): Prevalence of F. alocis in all of the samples collected from GAP patients, CP patients and PR subjects as determined by dot blot hybridization using oligonucleotide probes. (b): Prevalence of F. alocis (F. a.), P. gingivalis (P. g.), P. intermedia (P. i.), A. actinomycetemcomitans (A. a.), T. denticola (T. d.), T. forsythia (T. f.), and F. nucleatum (F. n.) in the deepest pocket of each patient.