UBC Theses and Dissertations
Comparison between standard in vitro virulence associated assays and human coproantibody siga production as predictors of Yersinia enterocolitica and Yersinia enterocolitica-like organism associated mouse virulence and human disease presentation Fletcher, Kathleen Margaret
A semi-quantitative indirect immunofluorescence assay was developed which distinguishes two types of patients from whom yersiniae are recovered: those who produce a strong yersiniae specific coproantibody secretory IgA (SIgA) response and those who do not. This SIgA response appeared to be yersiniae specific as faecal supernatant controls from patients whose stools where shown to yield negative or positive cultures for Salmonella, Campylobacter, or Clostridia were SIgA negative. Organisms isolated from patients with high SIgA titers had a higher incidence of virulence associated characteristics although SIgA response was not associated with most other commonly recognized assays of virulence. A strong association was shown to exist between SIgA titre and mouse virulence, the gold standard of bacterial virulence. Clinical examination of patients culture positive with yersiniae documented a strong association between acute enteric illness and high SIgA titre. This association was not dependant on the cultured yersiniae species. No single in vitro virulence associated assay was found to be a reliable predictor of animal virulence. The virulence of nine Y.frederiksenii and one Y.kristensenii, previously thought to be non-pathogenic in man, was also documented.
Item Citations and Data