High-Throughput Bacteriophage Testing with Potency Determination: Validation of an Automated Pipetting and Phage...

Area of Science:

• Microbiology
• Biotechnology
• Pharmaceutical Science

Background:

• Bacteriophages (phages) are emerging as active pharmaceutical ingredients for treating infections.
• Regulatory bodies require robust methods for assessing phage potency.
• Current manual plaque assays for phage potency are labor-intensive and hinder high-throughput screening.

Purpose of the Study:

• To develop and validate a high-throughput automated method for bacteriophage potency determination.
• To compare the automated method with the traditional manual assay for accuracy and reproducibility.
• To facilitate the efficient screening of numerous phage candidates for therapeutic potential.

Main Methods:

• Utilized a liquid-handling robot for automated pipetting and phage drop-off.
• Tested ten phages individually and as a cocktail against 126 Escherichia coli strains.
• Validated the automated method against a manual assay using Bland and Altman analysis and Lin's concordance correlation coefficient.

Main Results:

• The automated method demonstrated high reproducibility and concordance with the manual assay (concordance correlation coefficient: 0.86).
• Automated pipetting resulted in lower coefficients of variation (mean CV: 13.3%) compared to manual methods (24.5%).
• The system successfully tested multiple phages and strains, enabling high-throughput phage potency determination.

Conclusions:

• An automated liquid-handling system provides a reliable, efficient, and reproducible method for bacteriophage potency evaluation.
• This high-throughput approach significantly speeds up phage screening and potency assessment.
• The method offers potential for standardizing phage potency testing in the development of phage therapeutics.