Although Zot has been shown to disrupt epithelial tight junctions, we did not observe any changes in permeability or TER of epithelial monolayers throughout the 3 h incubation period for any of the isolates. This is contrary to the observation of Man et al., that C. concisus caused increased epithelial permeability, decreased TER, and loss of membrane-associated zonnula occludens and occludin in epithelial monolayers [33]. Possible reasons for this

discrepancy include variation in methodology between the two studies (i.e., Man et al. inoculated Caco-2 cells with an MOI of 200, and assessed barrier function 6 h-post inoculation.). Conclusion In summary, two main genomospecies were Mocetinostat identified among fecal isolates of C. concisus from healthy and diarrheic individuals. The genomospecies differed with respect to clinical presentation and selleck inhibitor pathogenic properties,

which is consistent with the hypothesis that certain genomospecies have different pathogenic potential. AFLP cluster 2 was predominated by isolates belonging to genomospecies B and those from diarrheic individuals. Isolates from this cluster displayed higher NVP-HSP990 chemical structure mean epithelial invasion and translocation than cluster 1 isolates, consistent with a potential role in inflammatory diarrhea and occasional bacteraemia. In contrast, isolates assigned to AFLP cluster 1 belonged to genomospecies A and were predominantly (but not strictly) isolated from healthy individuals. Isolates assigned to this cluster induced

greater expression of epithelial IL-8 mRNA and more frequently contained genes coding for the zonnula occludins toxin and the S-layer RTX. Furthermore, isolates from healthy individuals induced greater apoptotic DNA fragmentation and increased metabolic activity than did isolates from diarrheic individuals, and isolates assigned to genomospecies A (of which the majority were from healthy individuals) exhibited higher haemolytic activity compared to genomospecies B isolates. This suggests that isolates from this cluster may also cause disease, albeit via different mechanisms than isolates from AFLP cluster 2. AFLP cluster 1 contains a reference strain isolated from the oral cavity, thus it is possible that this cluster contains isolates that are primarily periodontal pathogens. While in vitro pathogenicity assessments Vorinostat cell line are informative, they do not necessarily correspond with the ability of an isolate to cause disease in vivo. Clearly, further studies, particularly in vivo, are needed to confirm that these genetically distinct groups of C. concisus indeed differ in their ability to cause intestinal disease. In this regard, comparative genomic and pathogenicity examinations using animal models have been initiated. Methods Bacterial isolates and growth conditions A total of 23 C. concisus isolates recovered from different individuals were used in this study (Table 1). These included five isolates recovered from the stools of healthy volunteers (i.e.