Work

Isolation, preliminary In Vitro screening, and In Vivo biosafety evaluation of a Siphoviridae bacteriophage against drug-resistant Salmonella Typhimurium

Year: 2025

Type: article

Abstract: BACKGROUND: The increasing global threat of drug-resistant Salmonella Typhimurium has renewed interest in bacteriophage therapy as a viable alternative to conventional antibiotics. METHODS: This study aimed to isolate and investigate a specific bacteriophage that targets Salmonella Typhimurium ATCC 14028, and to evaluate its effects in rats. The bacterial strain was identified using the VITEK® 2 system, which also confirmed its reduced sensitivity to several standard antibiotics. The microscopic characteristics of the isolated bacteriophages were determined using transmission electron microscopy. Given the difficulty of inducing a Salmonella infection in rats or mice, the In vivo study evaluated the phage's effects on healthy, uninfected rats. The experiment involved a control, an antibiotic-treated group, and a bacteriophage-treated group. All treatments were delivered via intraperitoneal injection. Throughout the study, rats were monitored for behavioral changes, body weight, and histopathological and hematological parameters in the liver and spleen. RESULTS: A lytic bacteriophage was successfully isolated from untreated sewage, with Salmonella Typhimurium serving as the propagation host. Preliminary taxonomic classification, performed using transmission electron microscopy (TEM), suggested its affiliation with the Siphoviridae family. Furthermore, In Vitro assays provided evidence of the phage's robust lytic activity against the target bacterial strain. The hematological analysis of the group treated with the isolated bacteriophage revealed significant changes, including a decrease in red blood cell counts and hemoglobin levels, alongside notable shifts in leukocyte distribution compared to the control group. Histopathological examinations of the liver indicated mild hepatic steatosis and scattered inflammatory cell infiltration. CONCLUSIONS: In conclusion, while the isolated Siphoviridae phage demonstrated potent In vitro activity against drug-resistant Salmonella Typhimurium strain, its administration to healthy rats induced measurable changes in both their blood profiles and tissue structures. These findings highlight the critical need for further safety and immunological studies before considering this phage for therapeutic use.

Source: Journal of Infection and Public Health

DOI: 10.1016/j.jiph.2025.103063

Authors: Abdulmalik B. Alowayyid, Ahmed S. Alobaidi, Shine Kadaikunnan, Adel A. Abdulmanea, Mohammed S. Alharbi, Jamal M. Khaled

Institution: King Saud University

Language: English

Topic: Bacteriophages and microbial interactions

Subfield: Ecology

Field: Environmental Science

Domain: Physical Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $2,310