ARCIMS 26
in
Sunday 2025-10-19 18:49
Evaluation of a Siphovirus Phage as an Alternative Therapeutic Agent Against Multidrug-Resistant Acinetobacter baumannii
Elnaz Loloei 1 ℗, Sanaz Rastegar 2, Hossein Hosseini-Nave 3, Salehe Sabouri 4 ©
Abstract
Introduction: The rapid emergence of multidrug-resistant (MDR) Acinetobacter baumannii has created a global health concern, particularly in hospital settings where treatment options are limited. Bacteriophage therapy is emerging as a promising alternative. This study focused on assessing the antibacterial activity and safety profile of a specific siphovirus phage targeting MDR A. baumannii isolates under both culture and cell-based conditions. Methods and Materials: An MDR A. baumannii isolate was employed as the host for the propagation of the siphovirus phage. The phage titer was determined using the top agar overlay method. The multiplicity of infection (MOI) for the phage was determined by turbidity measurements, based on optical density readings at 600 nm (OD600). Phage stability was evaluated in both Nutrient Broth (NB) and Dulbecco’s Modified Eagle Medium(DMEM). Cytotoxic effects were assessed via MTT assay on human alveolar epithelial cells (A549) and mouse fibroblast cells (3T3). The phage's therapeutic potential was tested and cell viability and bacterial reduction were assessed through MTT assay and OD600 measurments, respectively. Results: Siphovirus phage inhibited A. baumannii growth effectively at an MOI of 10. It retained higher stability in NB than in DMEM. MTT results confirmed its safety for both A549 and 3T3 cell lines. Pre-treatment of A549 cells with the phage yielded an improvement in cell survival and bacterial clearance. Conclusion and Discussion: The study highlights the strong antibacterial effect of the phage against MDR A. baumannii, with no evident cytotoxicity in mammalian cells. Using phages befor infecting A549 cells with A. baumannii was effective in eradicating the bacterial infection. Using this phage was also safe for the mammalian cells.
Keywords: Acinetobacter baumannii, bacteriophage, A549 cell line, 3T3 cell line
