Knafl D, Tobudic S, Cheng S C, Bellamy D R, Thalhammer F
Division of Infectious Diseases and Tropical Medicine, Department of Medicine I, Medical University Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
Eur J Clin Microbiol Infect Dis. 2017 Apr;36(4):677-680. doi: 10.1007/s10096-016-2845-z. Epub 2016 Nov 28.
Activity of dalbavancin against methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus epidermidis (MRSE) in biofilm was investigated and the microbicidal biofilm concentrations (MBC) were determined. Biofilms obtained from ten MRSA and ten MRSE bloodstream isolates, collected from patients in the General Hospital of Vienna between 2012 and 2015, were incubated with dalbavancin in trypticase soy broth (TSB) in serial dilution from 0.0625 mg/l to 256 mg/l using a microtiter plate biofilm model. The plates were incubated for 24 h at 37 ° C and 50% humidity. Biofilms were fixed with 2.5% glutaraldehyde and stained with crystal violet. Subsequently the optical density (OD) was used to measure the MBC, defined as the concentration of dalbavancin leading to a 50% reduction of biofilm. MBC for MRSA was 1 mg/l-4 mg/l (minimal inhibitory concentrations (MIC) 0.0312 mg/l-0.064 mg/l). MBC for MRSE was 2 mg/l-16 mg/l (MIC 0.023 mg/l-0.0625 mg/l). Dalbavancin successfully reduced MRSA and MRSE in biofilms, and therefore provides a promising option for the treatment of biofilm-associated infections.
研究了达巴万星对生物膜中耐甲氧西林金黄色葡萄球菌（MRSA）和耐甲氧西林表皮葡萄球菌（MRSE）的活性，并测定了杀菌生物膜浓度（MBC）。使用微量滴定板生物膜模型，将2012年至2015年间从维也纳总医院患者中收集的10株MRSA和10株MRSE血流分离株所形成的生物膜，与达巴万星在胰蛋白酶大豆肉汤（TSB）中进行系列稀释孵育，浓度范围为0.0625mg/l至256mg/l。平板在37℃和50%湿度下孵育24小时。生物膜用2.5%戊二醛固定，并用结晶紫染色。随后，使用光密度（OD）测量MBC，MBC定义为导致生物膜减少50%的达巴万星浓度。MRSA的MBC为1mg/l至4mg/l（最低抑菌浓度（MIC）为0.0312mg/l至0.064mg/l）。MRSE的MBC为2mg/l至16mg/l（MIC为0.023mg/l至0.0625mg/l）。达巴万星成功降低了生物膜中的MRSA和MRSE，因此为治疗生物膜相关感染提供了一个有前景的选择。
