title: Effect of different antibacterial agents and surfactant protein-A (SP-A) on adherence of some respiratory pathogens to bronchial epithelial cells.
abstract: Some antibiotics at sub-inhibitory concentrations are able to alter bacterial surface structures and modulate adhesiveness by affecting the expression of microbial adhesins. An important mechanism of pulmonary defence against pathogens is SP-A, one of the proteins of the alveolar surfactant having opsonizing activity. The aim of this study was to investigate the effect that sub-inhibitory concentrations of different antibiotics and physiological concentrations of SP-A (1 and 5 microg/ml) could exert on the adherence of respiratory pathogens to the bronchial epithelial cell line, WI26VA4. Cefdinir and clarithromycin showed high efficacy, mainly at 1/2 MIC, in reducing the adherence of Staphylococcus aureus, Streptococcus pneumoniae and Haemophilus influenzae strains to values lower or equal to 50% of the control; sparfloxacin showed the same effect on S. aureus and S. pneumoniae but teicoplanin only on S. pneumoniae. Other similar results were observed with netilmicin on Klebsiella pneumoniae (40%) and with cefepime and ciprofloxacin on Pseudomonas aeruginosa (60%). Clarithromycin reduced the adherence of K. pneumoniae to 80% although it is not active against this strain. Adherence of the test strains was not modified by SP-A alone or in combination with any of the antibiotics used.
authors.affiliation: 1st. Mal. App. Respiratorio (Forlanini), IRCCS Policlinico S. Matteo, Viale Taramelli, 5-27100, Pavia, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Ferrara
authors.forename: C
authors.initials: C
authors.lastname: Dos Santos
authors.forename: A
authors.initials: A
authors.lastname: Lupi
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D001422:Bacterial Adhesion / Q000187:drug effects*; D002460:Cell Line; D002511:Cephalosporins / Q000494:pharmacology; D017291:Clarithromycin / Q000494:pharmacology; D024841:Fluoroquinolones; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000502:physiology*; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D008826:Microbial Sensitivity Tests; D009428:Netilmicin / Q000494:pharmacology; D011510:Proteolipids / Q000494:pharmacology / Q000502:physiology*; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000382:microbiology*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000494:pharmacology / Q000502:physiology*; D020545:Respiratory Mucosa / Q000187:drug effects / Q000382:microbiology*; D017334:Teicoplanin / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D002511:Cephalosporins; D024841:Fluoroquinolones; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D009428:Netilmicin; D017334:Teicoplanin; D017291:Clarithromycin