HEp-2 cell adherence and Vero cell cytotoxin production by EPEC strains isolated from children with diarrhoea in New Zealand.
A total of 112 EPEC strains isolated from children with diarrhoea in New Zealand were examined for mannose-resistant HEp-2 cell adherence and production of exotoxins. Enterotoxin production was not detected in any of the strains examined. Verotoxin production was detected in 13 (11.6%) strains and of these 4 were also found to adhere to HEp-2 cells. HEp-2 cell adherence was displayed by a total of 29 (25.8%) strains of which 22 were diffusely adherent. Only 3 (2.7%) strains were shown to belong to the new virulence phenotype, entero-aggregative adherence, when examined in the adherence assay. We identified one strain with the novel characteristic of causing detachment of HEp-2 cells from glass coverslips and are further investigating this possible virulence mechanism. These results suggest that if EPEC strains are to be considered as a cause of diarrhoea, the search for new virulence factors must be extended.
Department of Microbiology, University of Western Australia.
S T
ST
Gunzburg
V
V
Burke
K A
KA
Bettelheim
D000818:Animals; D000942:Antigens, Bacterial; D001422:Bacterial Adhesion; D001427:Bacterial Toxins / Q000096:biosynthesis*; D002460:Cell Line; D003603:Cytotoxins / Q000096:biosynthesis*; D003967:Diarrhea / Q000382:microbiology*; D004926:Escherichia coli / Q000276:immunology / Q000378:metabolism* / Q000472:pathogenicity; D006801:Humans; D007223:Infant; D009520:New Zealand; D022622:Shiga Toxin 1; D014709:Vero Cells; D014774:Virulence
D000942:Antigens, Bacterial; D001427:Bacterial Toxins; D003603:Cytotoxins; D022622:Shiga Toxin 1