title: Potential effects of erythromycin on host defense systems and virulence of Pseudomonas aeruginosa.
abstract: We evaluated several potential effects of erythromycin (EM) on host defense systems and the virulence of Pseudomonas aeruginosa. Peritoneal macrophages obtained from mice given 250 mg of EM per kg of body weight for 7 days by the intraperitoneal, intravenous, subcutaneous, or oral route produced significantly greater amounts of thymocyte-activating factors. These data suggest that EM enhances the in vivo production of cytokines, such as interleukins 1 and 6. Treatment of P. aeruginosa D4 with subinhibitory concentrations of EM enhanced the association of bacteria with murine Kupffer cells in vitro and increased bacterial clearance from the blood in mice. EM suppressed the in vitro production of exotoxin A, total protease, elastase, and phospholipase C by P. aeruginosa D4; exotoxin A production by P. aeruginosa PA-103; and total protease production by P. aeruginosa B16 and PAO1 in a generally dose-dependent manner. These data demonstrate that EM produces various effects in addition to its direct antimicrobial activity, suggesting that it has potential as an immunomodulator or bacterial virulence-suppressing agent against P. aeruginosa and other infections.
authors.affiliation: Department of Microbiology, Toho University School of Medicine, Tokyo, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hirakata
authors.forename: M
authors.initials: M
authors.lastname: Kaku
authors.forename: R
authors.initials: R
authors.lastname: Mizukane
authors.forename: K
authors.initials: K
authors.lastname: Ishida
authors.forename: N
authors.initials: N
authors.lastname: Furuya
authors.forename: T
authors.initials: T
authors.lastname: Matsumoto
authors.forename: K
authors.initials: K
authors.lastname: Tateda
authors.forename: K
authors.initials: K
authors.lastname: Yamaguchi
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D001426:Bacterial Proteins / Q000096:biosynthesis; D004917:Erythromycin / Q000494:pharmacology*; D007728:Kupffer Cells / Q000187:drug effects / Q000382:microbiology; D008264:Macrophages / Q000187:drug effects; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008826:Microbial Sensitivity Tests; D011552:Pseudomonas Infections / Q000201:enzymology / Q000276:immunology* / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000276:immunology / Q000472:pathogenicity*; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D001426:Bacterial Proteins; D004917:Erythromycin