title: Serotype-related HEp-2 cell interaction of Yersinia enterocolitica.
abstract: The ability of human clinical isolates of Yersinia enterocolitica to interact with HEp-2 cells was found to vary considerably between the serotypes O:3, O:8, and O:9. Although all three serotypes adhered initially to the cell surface, regardless of incubation temperature of the bacterial inoculum or presence of the 40- to 48-megadalton virulence plasmid, the ability to localize intracellularly was not uniformly expressed. By using a combined light optical method based on differential interference contrast and UV incident light microscopy, we found that in serotype O:3, resistance to internalization was dependent upon prior growth at 37 degrees C and carriage of the virulence plasmid; in serotype O:9, this property was plasmid dependent but not temperature dependent; in serotype O:8, it was constitutive. The ability of serotype O:3 to resist internalization was correlated with the expression of plasmid-associated fibrillae on the bacterial surface. No relationship between fibrillation and HEp-2 cell interaction was apparent for serotype O:8 or O:9. Serotypes O:8 and O:9, unlike the O:3 strains studied, associated with HEp-2 cells in greater number after cultivation at 22 degrees C than after cultivation at 37 degrees C. We failed to establish a correlation between the expression of surface fibrillae and the ability to evoke guinea pig conjunctivitis.
authors.forename: J
authors.initials: J
authors.lastname: Lassen
authors.forename: G
authors.initials: G
authors.lastname: Kapperud
mesh_terms: D000818:Animals; D002460:Cell Line; D003231:Conjunctivitis / Q000382:microbiology; D004848:Epithelium / Q000382:microbiology; D010861:Fimbriae, Bacterial / Q000502:physiology; D006168:Guinea Pigs; D006801:Humans; D010957:Plasmids; D012703:Serotyping; D015008:Yersinia enterocolitica / Q000145:classification / Q000472:pathogenicity*