Adherence of Bordetella bronchiseptica to swine nasal epithelial cells and its possible role in virulence.
Bordetella bronchiseptica phase I organisms adhered well to swine nasal epithelial cells cultured in vitro, while phase III variants exhibited feeble adherence to the same cells. Similarly, firm attachment of phase I organisms and poor adhesion of phase III organisms to nasal epithelium were demonstrated in experimentally infected piglets. Electron microscopic observations of nasal mucosa infected with phase I organisms showed preferential adherence to the cilia of nasal epithelial cells; the association of bacteria and cilia appeared to be mediated by fuzzy or string-like surface appendages which extended out from the bacterial cell wall. The ability to attach to epithelial cells was significantly reduced by heating the bacteria at 100 degrees C for 1 h or by pretreatment with 1 per cent formalin. Trypsin digestion treatment did not greatly reduce the adherence. Rabbit antisera to living or formalinised phase I organisms markedly impaired the attachment of the bacteria. However, antisera to heated phase I organisms or living phase III organisms did not show inhibitory effects. These data indicate that the heat labile surface component which is specific to phase I organisms may function in the adherence of the bacteria to swine nasal epithelium.
D000818:Animals; D001884:Bordetella / Q000254:growth & development* / Q000472:pathogenicity / Q000648:ultrastructure; D001885:Bordetella Infections / Q000382:microbiology / Q000662:veterinary; D002478:Cells, Cultured; D002923:Cilia / Q000382:microbiology / Q000648:ultrastructure; D004848:Epithelium / Q000382:microbiology / Q000648:ultrastructure; D006358:Hot Temperature; D008855:Microscopy, Electron, Scanning; D009297:Nasal Mucosa / Q000382:microbiology* / Q000648:ultrastructure; D013552:Swine; D013553:Swine Diseases / Q000382:microbiology; D014774:Virulence