Improved sensitivity of diagnosis of tuberculosis in patients in Korea via a cocktail enzyme-linked immunosorbent assay containing the abundantly expressed antigens of the K strain of Mycobacterium tuberculosis

A. Rum Shin, Jae Shin Sung, Kil Soo Lee, Sun Ho Eom, Seung Sub Lee, Byung Soo Lee, Ji Sook Lee, Nae Cho Sang, Hwa Jung Kim

Research output: Contribution to journalArticle

36 Citations (Scopus)


Tuberculosis (TB) is the leading cause of death from a single infectious agent in Korea. In this study, we compared the proteins present in culture filtrates from Mycobacterium tuberculosis strain K, which is the dominant clinical isolate in Korea, with those present in culture filtrates from M. tuberculosis H37Rv. Several differences in expression were detected between the two strains for those proteins with a molecular mass of <20 kDa. ESAT-6, HSP-X, and CFP-10 were found to be abundantly expressed in the strain K culture filtrates by liquid chromatography-electrospray ionization-time of flight mass spectrometry. The serodiagnostic potentials of recombinant antigens rESAT-6, rHSP-X, and rCFP-10 and two native antigens (Ag85 and PstS1) were evaluated by Western blot analysis and enzyme-linked immunosorbent assay (ELISA) using sera collected from 46 TB patients with active disease and 46 healthy controls. As for our ELISA results, HSP-X was superior to the other antigens in terms of sensitivity when a single antigen was employed. The results of a receiver operator characteristic analysis revealed that a cocktail ELISA using all five antigens was significantly more sensitive (77.8%) than the use of a single antigen and offered equivalent specificity; moreover, it produced the largest area under the curve (0.91 versus 0.55 to 0.87). Therefore, a cocktail ELISA containing abundantly expressed antigens enhances the sensitivity of a single antigen and can be a useful diagnostic tool for the detection of active TB.

Original languageEnglish
Pages (from-to)1788-1795
Number of pages8
JournalClinical and Vaccine Immunology
Issue number12
Publication statusPublished - 2008 Dec 1


All Science Journal Classification (ASJC) codes

  • Immunology and Allergy
  • Immunology
  • Clinical Biochemistry
  • Microbiology (medical)

Cite this