TY - JOUR
T1 - RNAIII-inhibiting peptide significantly reduces bacterial load and enhances the effect of antibiotics in the treatment of central venous catheter-associated Staphylococcus aureus infections
AU - Cirioni, Oscar
AU - Giacometti, Andrea
AU - Ghiselli, Roberto
AU - Dell'Acqua, Giorgio
AU - Orlando, Fiorenza
AU - Mocchegiani, Federico
AU - Silvestri, Carmela
AU - Licci, Alberto
AU - Saba, Vittorio
AU - Scalise, Giorgio
AU - Balaban, Naomi
PY - 2006/1/15
Y1 - 2006/1/15
N2 - Background. Medical devices used in clinical practice are often associated with biofilm-associated staphylococcal infections. Methods. An in vitro antibiotic susceptibility assay of Staphylococcus aureus biofilms using 96-well polystyrene tissue-culture plates was performed to test the effects of RNAIII-inhibiting peptide (RIP), ciprofloxacin, imipenem, and vancomycin. Efficacy studies were performed using a rat model of central venous catheter (CVC)-associated infection. Twenty-four hours after implantation, the catheters were filled with RIP (1 mg/mL). Thirty minutes later, rats were challenged, via the CVC, with 1.0 × 106 cfu of S. aureus strain Smith diffuse. The antibiotic-lock technique was begun 24 h later. Results. Minimum inhibitory concentrations of antibiotics in biofilms were at least 4-fold higher than those against the freely growing planktonic cells. When they were first treated with RIP, the cells in biofilms became as susceptible to antibiotics as did planktonic cells. These data were confirmed by the in vivo studies. In particular, when CVCs were treated with both RIP and antibiotics, the biofilm bacterial load was further reduced to 1 × 101 cfu/mL, and bacteremia was not detected, suggesting that there was 100% elimination of bacteremia and a 6 log10 reduction in biofilm bacterial load. Conclusion. RIP significantly reduces bacterial load and enhances the effect of antibiotics in the treatment of CVC-associated S. aureus infections.
AB - Background. Medical devices used in clinical practice are often associated with biofilm-associated staphylococcal infections. Methods. An in vitro antibiotic susceptibility assay of Staphylococcus aureus biofilms using 96-well polystyrene tissue-culture plates was performed to test the effects of RNAIII-inhibiting peptide (RIP), ciprofloxacin, imipenem, and vancomycin. Efficacy studies were performed using a rat model of central venous catheter (CVC)-associated infection. Twenty-four hours after implantation, the catheters were filled with RIP (1 mg/mL). Thirty minutes later, rats were challenged, via the CVC, with 1.0 × 106 cfu of S. aureus strain Smith diffuse. The antibiotic-lock technique was begun 24 h later. Results. Minimum inhibitory concentrations of antibiotics in biofilms were at least 4-fold higher than those against the freely growing planktonic cells. When they were first treated with RIP, the cells in biofilms became as susceptible to antibiotics as did planktonic cells. These data were confirmed by the in vivo studies. In particular, when CVCs were treated with both RIP and antibiotics, the biofilm bacterial load was further reduced to 1 × 101 cfu/mL, and bacteremia was not detected, suggesting that there was 100% elimination of bacteremia and a 6 log10 reduction in biofilm bacterial load. Conclusion. RIP significantly reduces bacterial load and enhances the effect of antibiotics in the treatment of CVC-associated S. aureus infections.
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U2 - 10.1086/498914
DO - 10.1086/498914
M3 - Article
C2 - 16362881
AN - SCOPUS:30944435420
VL - 193
SP - 180
EP - 186
JO - Journal of Infectious Diseases
JF - Journal of Infectious Diseases
SN - 0022-1899
IS - 2
ER -