In response to the increasing incidence of TB infections, and due to the limitations of existing diagnostic tests in the areas of speed, sensitivity, and informativeness, we present a proposal to develop a fluorescence-based solid-phase nucleic acid testing system for TB diagnosis which is highly sensitive (able to detect TB in clinical samples prior to culturing and in smear-negative, TB-positive patients), rapid (< 8 hours), cost-effective (low screening cost) and highly informative (determination of mycobacterial species and antibiotic resistance in a single test). Feasibility for development of this testing system will be determined through the execution of the following four Phase I aims - AIM 1: Sensitive fluorescence-based hybridization and detection on glass using synthetic mycobacterial templates, AIM 2: Rapid and quantitative conversion of amplified templates from killed mycobacterial cells to hybridizable single-strands using TargEx(TM) biochemistry, AIM 3: Informative and flexibly formatted Genetic Bit Analysis (GBA(TM)) genotyping of species-differentiating variant nucleotides in synthetic templates derived from M. tuberculosis and M. avium, and AIM 4: Assessment and planning of Phase II objectives. These capabilities have the potential to function together in a Phase II prototype to provide significant operational and informational advantages over currently available TB diagnostic tests.Proposed commercial application:The major commercial application for the technology developed under this proposal will be a single, rapid automated test for mycobacterial species and drug resistance. This TB diagnostic testing system would also be generically applicable to many nucleic acid- based diagnoses of clinically relevant disease caused by infectious or non-infectious agents.National Institute of Allergy and Infectious Diseases (NIAID)
