title: Validation of nanodiamond-extracted CFP-10 antigen as a biomarker in clinical isolates of Mycobacterium tuberculosis complex in broth culture media.
abstract: With detonation nanodiamonds (DNDs) and matrix-assisted laser desorption/ionization mass spectrometry (MALDI-TOF MS), we previously identified early secreted cell filtrate protein 10 (CFP-10) as a candidate Mycobacterium tuberculosis complex (MTC) biomarker. The performance of the CFP-10 biomarker was initially evaluated in relatively small mycobacterial samples (n = 42 samples) in our previous study. In this study, we conducted DND MALDI-TOF MS experiments to investigate the specificity and sensitivity of the MTC biomarker with 312 MTC and 52 nontuberculous mycobacteria (NTM) clinical samples. The frequency and intensity of the acquired CFP-10 mass-to-charge (m/z) peaks were checked with a program to validate that the singly and doubly charged CFP-10 antigen can be treated as a MTC biomarker. We confirmed that by detecting the singly charged species of CFP-10 antigen, the sensitivity and the specificity of MTC samples could reach 97.4% and 100% and no CFP-10 biomarker could be found in NTM samples. This indicates with CFP-10 biomarker it is easy to distinguish MTC from NTM. Besides, the observed intensity ratio of singly and doubly charged species of CFP-10 antigen was 3.3 ± 2.6 and the CFP-10 antigen could maintain good signal intensity for a week. Our results suggest that, with the DND MALDI-TOF mass spectrometry approach, CFP-10 antigen can be used as an early diagnosis biomarker in clinical practice.
authors.affiliation: Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Taiwan.
authors.forename: Po-Chi
authors.initials: PC
authors.lastname: Soo
authors.affiliation: Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Taiwan.
authors.forename: Yu-Tze
authors.initials: YT
authors.lastname: Horng
authors.affiliation: Department of Physics, National Dong Hwa University, Shoufeng, Hualien, 97401, Taiwan.
authors.forename: Ai-Ti
authors.initials: AT
authors.lastname: Chen
authors.affiliation: Department of Physics, National Dong Hwa University, Shoufeng, Hualien, 97401, Taiwan.
authors.forename: Shih-Chieh
authors.initials: SC
authors.lastname: Yang
authors.affiliation: Department of Laboratory Medicine and Biotechnology, Tzu Chi University, Hualien, Taiwan.
authors.forename: Kai-Chih
authors.initials: KC
authors.lastname: Chang
authors.affiliation: Department of Internal Medicine, Buddhist Tzu Chi General Hospital and Tzu Chi University, Hualien, Taiwan.
authors.forename: Jen-Jyh
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Physics, National Dong Hwa University, Shoufeng, Hualien, 97401, Taiwan. Electronic address: pengw@mail.ndhu.edu.tw.
authors.forename: Wen-Ping
authors.initials: WP
authors.lastname: Peng
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D001431:Bacteriological Techniques / Q000295:instrumentation*; D015415:Biomarkers / Q000378:metabolism; D042241:Early Diagnosis; D006801:Humans; D009169:Mycobacterium tuberculosis / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D058612:Nanodiamonds; D036103:Nanotechnology / Q000295:instrumentation*; D011237:Predictive Value of Tests; D055550:Protein Stability; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013183:Sputum / Q000382:microbiology; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D001426:Bacterial Proteins; D015415:Biomarkers; C117940:CFP-10 protein, Mycobacterium tuberculosis; D058612:Nanodiamonds
keywords: CFP-10 antigen; Detonation nanodiamond; MALDI-TOF mass spectrometry; MGIT; MTC