Moore Kelly, Li Anthony, Gupta Niraj, Gupta Tripti Thapa, Delury Craig, Aiken Sean S, Laycock Phillip A, Stoodley Paul
Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH 43210, USA.
Biocomposites Ltd., Keele Science Park, Keele, Staffordshire ST5 5NL, UK.
Microorganisms. 2023 Sep 12;11(9):2296. doi: 10.3390/microorganisms11092296.
Multispecies biofilm orthopedic infections are more challenging to treat than mono-species infections. In this in-vitro study, we aimed to determine if a multispecies biofilm, consisting of Gram positive and negative species with different antibiotic susceptibilities could be treated more effectively using high purity antibiotic-loaded calcium sulfate beads (HP-ALCSB) containing vancomycin (VAN) and tobramycin (TOB) in combination than alone.
Three sets of species pairs from bioluminescent strains of (PA) and (SA) and clinical isolates, (EF) and were screened for compatibility. PA + EF developed intermixed biofilms with similar cell concentrations and so were grown on 316L stainless steel coupons for 72 h or as 24 h agar lawn biofilms and then treated with HP-ALCSBs with single or combination antibiotics and assessed by viable count or bioluminescence and light imaging to distinguish each species. Replica plating was used to assess viability.
The VAN + TOB bead significantly reduced the PA + EF biofilm CFU and reduced the concentration of surviving antibiotic tolerant variants by 50% compared to single antibiotics.
The combination of Gram-negative and positive targeted antibiotics released from HP-ALCSBs may be more effective in treating multispecies biofilms than monotherapy alone.
多物种生物膜性骨科感染比单一物种感染更具治疗挑战性。在这项体外研究中，我们旨在确定由具有不同抗生素敏感性的革兰氏阳性和阴性物种组成的多物种生物膜，使用含有万古霉素（VAN）和妥布霉素（TOB）的高纯度载抗生素硫酸钙珠（HP-ALCSB）联合使用是否比单独使用更有效地治疗。
从发光菌株（PA）和（SA）以及临床分离株（EF）和中筛选出三组物种对以检测其相容性。PA + EF形成了具有相似细胞浓度的混合生物膜，因此在316L不锈钢试片上培养72小时或作为24小时琼脂平板生物膜，然后用含单一或联合抗生素的HP-ALCSB处理，并通过活菌计数、生物发光和光成像来区分每个物种。影印接种法用于评估生存能力。
与单一抗生素相比，VAN + TOB珠显著降低了PA + EF生物膜的CFU，并使存活的抗生素耐受变异体浓度降低了50%。
从HP-ALCSB释放的革兰氏阴性和阳性靶向抗生素联合使用可能比单独的单一疗法更有效地治疗多物种生物膜。
