The State of the Art in Biodefense Related Bacterial Pathogen Detection Using Bacteriophages: How It Started and How It’s Going

Abstract

Accurate pathogen detection and diagnosis is paramount in clinical success of treating patients. There are two general paradigms in pathogen detection: molecular and immuno-based, and phage-based detection is a third emerging paradigm due to its sensitivity and selectivity. Molecular detection methods look for genetic material specific for a given pathogen in a sample usually by polymerase chain reaction (PCR). Immuno-methods look at the pathogen components (antigens) by antibodies raised against that pathogen specific antigens. There are different variations and products based on these two paradigms with advantages and disadvantages. The third paradigm at least for bacterial pathogen detection entails bacteriophages specific for a given bacterium. Sensitivity and specificity are the two key parameters in any pathogen detection system. By their very nature, bacteriophages afford the best sensitivity for bacterial detection. Bacteria and bacteriophages form the predator-prey pair in the evolutionary arms race and has coevolved over time to acquire the exquisite specificity of the pair, in some instances at the strain level. This specificity has been exploited for diagnostic purposes of various pathogens of concern in clinical and other settings. Many recent reviews focus on phage-based detection and sensor technologies. In this review, we focus on a very special group of pathogens that are of concern in biodefense because of their potential misuse in bioterrorism and their extremely virulent nature and as such fall under the Centers for Disease and Prevention (CDC) Category A pathogen list. We describe the currently available phage methods that are based on the usual modalities of detection from culture, to molecular and immuno- and fluorescent methods. We further highlight the gaps and the needs for more modern technologies and sensors drawing from technologies existing for detection and surveillance of other pathogens of clinical relevance.

Reporter-Phage-Based Detection and Antibiotic Susceptibility Testing of Yersinia pestis for a Rapid Plague Outbreak Response

“…Rapid detection and AST methods may allow fast containment of infectious patients, as well as allow for the proper treatment of the disease [1]. Various rapid tests have been described for the detection and AST of Y. pestis, including immunoassays (detection [18,19] and AST [20]), genetic assays (detection [21] and AST [17,22,23]), optical assays (AST [24]) and bacteriophage-based assays [25].…”

“…Bacteriophages (phages) are viruses that specifically lyse and kill bacteria and can thus serve for specific bacterial detection assays [25,26]. Phage-based detection methods have the advantage of being simple and inexpensive to manufacture and store [25], preventing reagent shortages in cases of global need.…”

“…Bacteriophages (phages) are viruses that specifically lyse and kill bacteria and can thus serve for specific bacterial detection assays [25,26]. Phage-based detection methods have the advantage of being simple and inexpensive to manufacture and store [25], preventing reagent shortages in cases of global need. Various phage-based detection methods for different pathogens have been developed based on native phages, phage peptides, biosensors, combinations of phages with PCR or immunoassays, and genetically engineered reporter phages (see recent reviews [25,27,28]).…”