[Adherence of Pseudomonas aeruginosa to mouse tracheal epithelium--the effect of antimicrobial agents].
The adherence of bacteria to mucosal surfaces is an important initial event in the pathogenesis of most bacterial infectious diseases. In order to clarify the mechanism of respiratory tract infections caused by Pseudomonas aeruginosa, we paid attention to pili (fimbriae), which is one of the adherence factors for the nonmucoid strains of P. aeruginosa. The adherence of P. aeruginosa was studied using two mutants: piliated and nonpiliated strains and 0.1 N hydrochloric acid-injured mouse tracheal epithelium as a respiratory tract model. The adherence ability was evaluated by means of direct count of adhered bacteria using a scanning electron microscope. The effect of antimicrobial agents was studied on the adherence and the production of pili. Both mutants of P. aeruginosa adhered more significantly to the acid-injured tracheal epithelium than the normal one (p less than 0.01). The number of the piliated strain adhering to the acid-injured tracheal epithelium was significantly greater than that of the nonpiliated strain (p less than 0.01). The piliated bacteria treated with heat, formalin, antiserum against pili, N-acetylneuraminic acid and N-acetylglucosamine showed a significant decrease in number of adherence. The piliated bacteria were grown in a media containing 1/4 MICs of seven antimicrobial agents for four hours at 37 degrees C, after that a significant reduction in the number of pili per bacterium was recognized with erythromycin, minocycline and clindamycin (p less than 0.01). The piliated bacteria treated with erythromycin showed a significant decrease on adherence to the acid-injured tracheal epithelium in parallel with piliation.(ABSTRACT TRUNCATED AT 250 WORDS)
Yamasaki
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Second Department of Internal Medicine, Medical College of Oita.
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001422:Bacterial Adhesion / Q000187:drug effects*; D001980:Bronchi / Q000382:microbiology*; D004305:Dose-Response Relationship, Drug; D010861:Fimbriae, Bacterial / Q000502:physiology*; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D011552:Pseudomonas Infections; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D012141:Respiratory Tract Infections / Q000209:etiology / Q000517:prevention & control
D000900:Anti-Bacterial Agents