Assessment of Therapeutic Potential of Bacteriophages to Control Escherichia Coli Infection in Swiss Mice Model

Abstract

Escherichia coli is one of the causes of infections in human and farm animals.Bacteriophages (or phages) have been proposed as natural antimicrobial agents to killbacterial cells within human or animal bodies. The study aimed to isolate phages againstE. coli from sewage sources and used it as a candidate for therapeutic purpose againstlethal dose of bacterial infection in Swiss mice model. Lytic phage was isolated fromsewage water collected in Jimma town following standard enrichment method against E.coli. The bacterium was obtained from Jimma University Specialized Hospitalbacteriology laboratory. Phage characterization as well as E. coli identification wasperformed. Lytic phage was used to assess survival of mice health from lethal dose(LD100) of E. coli infection.Three bacteriophages were isolated from among 5 differentsewage sources processed. One of the three selected bacteriophages has a mean of 5 mmplaque size and resistant to chloroform and ether. This phage was selected and used inmice model and inoculation of mice with high-dose of фJS3 phage alone produced noadverse effects. Then swiss mice injected intraperitoneally with the lethal dose of E. coli(10 9 CFU/ml) was grouped into three categories. Group one with six mice was givenstandardized number of lytic phages (10 9 PFU/ml), the second with antibiotic treatmentand the third as control group was given sterile physiologic saline. 10 9 CFU/ml E.coli cells caused death in the control mice within 5 days. In contrast, intraperitonealadministration of purified bacteriophage or antibiotic suppressed E. coli lethality in mice(100% survived). This study supports the view that bacteriophages are common inJimma area and could be useful in the treatment of animal infections caused bypathogenic bacteria