title: Mycobacterium tuberculosis Secreted Proteins As Potential Biomarkers for the Diagnosis of Active Tuberculosis and Latent Tuberculosis Infection.
abstract: BACKGROUND
  The detection of Mycobacterium tuberculosis (Mtb) specific human antibodies has been an important diagnostic aid in the diagnosis of tuberculosis (TB) cases with smear-negative sputum samples, especially for the screening of high-risk population. This study focused on the analysis and comparison of the four potential Mtb-secreted proteins (ESAT6, CFP10, Ag85B, Hsp16.3) and the fusion protein Ag85B-Hsp16.3 as new markers in the serodiagnosis between active TB and latent TB infection (LTBI).
  
  
  METHODS
  These five recombinant proteins were produced and used in optimized ELISA to detect IgG serum antibodies against the four secreted proteins. The capacity of identifying infection was evaluated either in active TB patients or LTBI individuals, which was compared with the control groups consisting of hospitalized non-TB individuals.
  
  
  RESULTS
  The results showed that Ag85B-Hsp16.3/ESAT6 and Hsp16.3/ESAT6 were the best-associated antigens for serology diagnosis of the active TB and LTBI individuals because of their specificity, sensitivity, YI values, and positive rates, respectively. ELISA test demonstrated that 41.67% (25/60) of blood donors respond to Ag85B-Hsp16.3/ESAT6. The consistency of this positive respond with clinical diagnosis almost reached 84% (21/25).
  
  
  CONCLUSIONS
  Thus, a combined test of multiple Mtb-secreted proteins Ag85B, Hsp16.3, and ESAT6 may be the ascendant preliminary screening antigens for active TB or LTBI patients.
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Caiqin
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Song
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Hai
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Shanmin
authors.initials: S
authors.lastname: Zhao
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Fengfeng
authors.initials: F
authors.lastname: Mao
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Bai
authors.affiliation: Department of Radiology, First Affiliated Hospital, Chengdu Medical College, Chengdu, P.R. China.
authors.forename: Shaoping
authors.initials: S
authors.lastname: Wu
authors.affiliation: Division of Infection and Immunology, Laboratory Animal Center, Fourth Military Medical University, Xi'an, P.R. China.
authors.forename: Changhong
authors.initials: C
authors.lastname: Shi
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood* / Q000276:immunology; D000942:Antigens, Bacterial / Q000276:immunology*; D001426:Bacterial Proteins / Q000276:immunology; D015415:Biomarkers / Q000097:blood*; D015331:Cohort Studies; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D055985:Latent Tuberculosis / Q000175:diagnosis; D009169:Mycobacterium tuberculosis / Q000737:chemistry / Q000276:immunology* / Q000302:isolation & purification; D012372:ROC Curve; D014376:Tuberculosis / Q000175:diagnosis*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D015415:Biomarkers; D007074:Immunoglobulin G
keywords: Ag85B; CFP10; ESAT6; Hsp16.3; M. tuberculosis (Mtb); diagnosis; tuberculosis (TB)