Ultra-Rapid Optical Platform for Antimicrobial Susceptibility Testing (AST) ofPulmonary Non-Tuberculous Mycobacterial (NTM) Infections

Project Summary: Nontuberculous Mycobacteria (NTM) encompass over 200 distinct bacterial species naturally occurring in the environment. Among these, the Mycobacterium avium complex (MAC) stands out as one of the most prevalent, and it will be a focal point in this project. Our selection of M. abscessus and MAC as subjects stems from their classification as rapidly growing, multidrug- resistant NTM species prevalent in soil and water. Notably, the treatment of pulmonary NTM diseases faces challenges due to elevated rates of antibiotic resistance. Recently, we pioneered a novel, rapid (< one hour) Antibiotic Susceptibility Testing (AST) technique. This method leverages the universal rapid stress responses of bacteria, coupled with the sensitivity and specificity of Surface-Enhanced Raman Spectroscopy (SERS), to deliver unprecedentedly fast and accurate drug susceptibility determinations. We aim to optimize the impact of this rapid SERS-AST method by developing components to parallelize signal acquisitions. This will enable simultaneous acquisition of quantitative drug susceptibility profiles (Minimum Inhibitory Concentration, MIC) for a range of antibiotics, facilitating optimal drug selection for treating NTM infections. Our project will be divided into three main aims. Initially, we will validate the concept of a parallel Raman reader for SERS-AST with a readout time of less than 5 minutes. Concurrently, we will design a SERS array card for rapid AST measurements. Finally, we will evaluate our SERS-AST assay using M. abscessus and MAC as target mycobacteria. Successful completion of these aims will pave the way for the development of a prototype system in Phase II, which will be directly comparable to commercial automated AST devices. Our target is to achieve a cost per test of $10, realized through an assay card format suitable for testing all pathogenic NTMs of interest.