Quantification of circulating Mycobacterium tuberculosis antigen peptides allows rapid diagnosis of active disease and treatment monitoring

Significance Active Mycobacterium tuberculosis ( Mtb ) infections represent a significant global health threat, but can be difficult to diagnose and manage owing to the nonquantitative nature and relatively poor performance of current frontline sputum-based diagnostic assays, which can be further degraded by certain Mtb manifestations. This study describes the development of a rapid and quantitative blood-based assay with high sensitivity and specificity for active Mtb infections that can be used to monitor responses to antimycobacterial therapy. Our method combines antibody-labeled, energy-focusing nanodisks with high-throughput mass spectrometry to enhance the detection of Mtb -specific peptides in digested serum samples, and should allow rapid clinical translation. This approach also should be applicable to other infectious diseases, particularly those for which conventional immunoassays exhibit suboptimal performance.