A highly sensitive 3base™ assay for detecting Streptococcus pyogenes in saliva during controlled human pharyngitis

Area of Science:

• Microbiology
• Molecular Diagnostics
• Infectious Diseases

Background:

• Streptococcus pyogenes (Group A Streptococcus; GAS) causes significant human illness.
• Current diagnostic methods like throat culture are slow, invasive, and low-throughput.
• Saliva as a diagnostic fluid for GAS detection is underutilized.

Purpose of the Study:

• To develop and validate a novel, high-throughput, sensitive, and robust speB quantitative PCR (qPCR) assay for GAS detection in saliva.
• To evaluate the feasibility of using saliva as a non-invasive diagnostic biofluid for GAS infections.
• To assess the performance of the 3base™ technology for detecting GAS in saliva samples.

Main Methods:

• Development of a novel speB qPCR assay utilizing 3base™ technology.
• Validation of the assay using saliva samples from the Controlled Human Infection for Vaccination Against Streptococcus (CHIVAS-M75) trial.
• Comparison of assay performance against traditional throat culture and conventional saliva qPCR.

Main Results:

• The novel 3base™-based speB qPCR assay demonstrated high throughput, sensitivity, and robustness in detecting GAS in saliva.
• The assay performance in saliva surpassed that of throat culture and conventional saliva qPCR in the CHIVAS-M75 trial samples.
• Successful validation of saliva as a viable biofluid for GAS detection using the developed assay.

Conclusions:

• The 3base™ qPCR assay provides a reliable and efficient method for non-invasive GAS detection in saliva.
• This study confirms the utility of the 3base™ platform and the feasibility of saliva-based diagnostics for GAS.
• The findings pave the way for developing novel, non-invasive diagnostic approaches for GAS and other oropharyngeal pathogens.