infection has been recognized as an increasingly important emerging disease in humans. Infection with H. cinaedi
causes bacteremia, cellulitis and enteritis. H. cinaedi
has been isolated from non-human sources, including dogs, cats and rodents; however, it remains unclear whether animal strains are pathogenic in humans and as zoonotic pathogens. In this study, H. cinaedi
isolates were recovered from a dog and a hamster, and the ability of these isolates to adhere to, invade and translocate across polarized human intestinal epithelial Caco-2 cells was examined in vitro.
To better understand the pathogenic potential of animal H. cinaedi
isolates, these results were compared with those for a human strain that was isolated from a patient with bacteremia. The animal and human strains adhered to and invaded Caco-2 cells, but to a lesser degree than the C. jejuni
81–176 strain, which was used as a control. The integrity of tight junctions was monitored by measuring transepithelial electrical resistance (TER) with a membrane insert system. The TER values for all H. cinaedi
strains did not change during the experimental periods compared with those of the controls; however, translocation of H. cinaedi
from the apical side to the basolateral side was confirmed by cultivation and H. cinaedi
-specific PCR, suggesting that the H. cinaedi
strains translocated by transcellular route. This study demonstrated that H. cinaedi
strains of animal origin might have a pathogenic potential in human epithelial cells as observed in a translocation assay in vitro
with a human isolate.