Ankara University Faculty of Pharmacy, Department of Pharmaceutical Microbiology, 06100, Ankara, Turkey.
Ankara University Faculty of Pharmacy, Department of Pharmaceutical Microbiology, 06100, Ankara, Turkey.
Microb Pathog. 2022 Jun;167:105563. doi: 10.1016/j.micpath.2022.105563. Epub 2022 May 2.
Antibiotic resistance is one of the crucial public health challenges. As a result of rising resistance, as an alternative to antimicrobials, demands for bacteriophage therapy have increased significantly over the years. The objective of this study was to isolate and characterize potentially therapeutic phages active against Escherichia coli (E. coli) and compare the efficacy with commercial Intesti bacteriophage on the extended-spectrum beta-lactamase (ESBL) positive E. coli (ESBL-EC) and performed the effectiveness of bacteriophage using the Galleria mellonella (G. mellonella) larvae model. Intesti bacteriophage is a polyvalent bacteriophage-based drug. The isolated bacteriophages were obtained from the river and clinical isolates of E. coli were used for the enrichment of bacteriophage isolation. The phages were first screened based on plaque morphology and host ranges determined on clinical strains. The susceptibility of phages was determined against 50 clinical isolates of E. coli and eight different laboratory isolates using the spot test technique. E. coli lytic phage Ec_P6 was used to determine the therapeutic and preventive effects on the G. mellonella larvae model. The slides were prepared by G. mellonella hemolymph for cytologic examination, stained with May Grünwald Giemsa (MGG), and evaluated by light microscopy. The results of the activities revealed lytic spectra ranging from 24% to 97%. Overall strains were susceptible to one or more phages from the panel. It was proved that Intesti bacteriophage is very effective in a wide variety of strains of E. coli including test strains, also showed that isolated Ec_P6 phage is as effective as commercial phage. The best MOI of this phage was 0.01, and infectivity decreased above 60 °C. The results suggest that phage is stable at pH values ranging between 5.0 and 9.0. In vivo study was found that in E. coli infection to achieve a survival high rate the infected larvae should be after 2 h treated with 0.01 MOI phage (10 μL, 10 PFU/mL) and colistin doses (10 μL, 2.5 mg/kg). It also prevented infection, increasing the survival of the larvae compared to the untreated control group. Ec_P6 phage was found to have a potential for the treatment of E. coli infections.
抗生素耐药性是公共卫生面临的主要挑战之一。由于耐药性的增加，噬菌体作为抗菌药物的替代品，其需求在近年来显著增加。本研究的目的是分离和鉴定对大肠杆菌（E. coli）具有潜在治疗作用的噬菌体，并与商品化的 Intesti 噬菌体比较对产超广谱β-内酰胺酶（ESBL）的大肠杆菌（ESBL-EC）的疗效，并使用金龟子幼虫（G. mellonella）模型评估噬菌体的有效性。Intesti 噬菌体是一种多价噬菌体药物。分离的噬菌体来自河流，使用临床分离的大肠杆菌进行噬菌体分离的富集。首先根据临床菌株的噬菌斑形态和宿主范围筛选噬菌体，然后使用点试验技术测定噬菌体对 50 株临床分离株和 8 株不同实验室分离株的敏感性。使用大肠杆菌裂解噬菌体 Ec_P6 测定其对金龟子幼虫模型的治疗和预防效果。用金龟子幼虫血淋巴制备载玻片，用于细胞学检查，用 May Grünwald Giemsa（MGG）染色，并用光学显微镜评估。活性结果显示裂解谱范围为 24%至 97%。总体而言，这些菌株对来自该试剂盒的一种或多种噬菌体敏感。结果证明，Intesti 噬菌体对包括测试菌株在内的各种大肠杆菌菌株都非常有效，同时还表明分离的 Ec_P6 噬菌体与商品化噬菌体一样有效。该噬菌体的最佳 MOI 为 0.01，在 60°C 以上时感染性下降。结果表明噬菌体在 pH 值 5.0 至 9.0 之间的范围内稳定。体内研究发现，在大肠杆菌感染中，为了获得高存活率，感染的幼虫应在 2 小时后用 0.01 MOI 噬菌体（10μL，10PFU/mL）和多粘菌素剂量（10μL，2.5mg/kg）进行治疗。与未处理的对照组相比，它还能预防感染，提高幼虫的存活率。Ec_P6 噬菌体具有治疗大肠杆菌感染的潜力。
