Here, we studied human pulmonary T-cell responses induced by the <i>M. tuberculosis</i>-specific antigen Rv3615c, a protein with a similar size and sequence homology to ESAT-6 and CFP-10, which induced dominant CD4<sup>+</sup> T-cell responses in human tuberculosis (TB) models.
Our results demonstrated that significantly higher levels of polyfunctional CD4(+) T cells for the epitopes of ESAT-6 or CFP-10 in PFCs may play an important role in the local control of tuberculosis (TB) infection.
Replacing Trp(55) (W55) or Gly(57) (G57) residues in the putative W-X-G motif of EspA with arginines impaired ESAT-6 and CFP-10 secretion in vitro and attenuated M. tuberculosis.
Thus, as for IGRA assays such as Quantiferon and T-Spot TB tests, ESAT-6 and CFP-10 are unable to distinguish LTBI from active TB when IL-2 is measured.
Highest diagnostic accuracies for active TB (AUC ≥ 0.91) were achieved for: (i) CD27 within IFN-γ<sup>+</sup>TNF-α<sup>+</sup>CD4<sup>+</sup> T-cells in response to ESAT-6/CFP-10, (ii) CD27 and CCR4 markers together within IFN-γ<sup>+</sup>CD4<sup>+</sup> T-cells in response to PPD, and (iii) CD27 MFI ratio performed on IFN-γ<sup>+</sup>TNF-α<sup>+</sup>CD4<sup>+</sup> T-cells after ESAT-6/CFP-10 stimulation.
The use of genetically detoxified Bordetella pertussis adenylate cyclase toxin (CyaA) as a delivery system for two immunodominant proteins of M. tuberculosis that are of greater specificity than PPD, early-secreted antigenic target 6-kDa protein (ESAT-6) and culture filtrate protein 10 (CFP-10), was therefore investigated.
Taken together, ESAT-6/CFP-10 cytokine tests together with detecting IgG antibodies specific to ESAT-6 and CFP-10 may be the useful TB disease biomarkers in monitoring treatment success.
However,the interferon-gamma release assay (IGRA) of the ascites was positive after specific stimulation with mycobacterial antigens(ESAT-6/CFP-10/TB7.7[p4]), indicating an infection with MTB.The diagnosis of tuberculosis was later confirmed by histology, MTB culture, and PCR analysis of MTB-complex DNA in tissue samples taken during laparoscopy.
For patients who received combination therapy with medium/high doses of corticosteroids, the T-SPOT.TB positive rate (p = 0.046) and CFP-10 spot number (p = 0.041) were increased after treatment, with no significant changes in the total number of spots or ESAT-6 spots.
This method exhibits great application potential in the field of nanomedical science for highly reliable point-of-care detection of CFP-10 antigen in real samples to early diagnosis of tuberculosis.
In contrast, responses to latency antigens were observed in individuals with suspected exposure to TB (as indicated by positive gamma interferon responses to TB-specific antigens ESAT-6 and CFP-10) and in mice vaccinated with plasmid DNA encoding selected latency antigens.
An electrochemical aptamer-based assay is described for the determination of CFP-10 which is an early secretary biomarker of Mycobacterium tuberculosis.
This study confirms the high conservation for ESAT-6, CFP-10 and EspC in local M. bovis field isolates and reinforce the use of these three antigens in the diagnosis of bovine tuberculosis.
Also, in this research, we proposed the incorporation of protein biomarker, Mycobacterium tuberculosis ESAT-6-like protein esxB (CFP-10), as a means of TB detection using plasmonic ELISA.
At the cellular level, only 2 of 45 mouse T-cell hybridomas raised against either M. leprae or M. tuberculosisCFP-10 displayed a cross-reactive response against the N-terminal heterologous CFP-10 peptide, the region that exhibits the highest level of identity in the two proteins; however, the majority of peptide epitopes recognized by mouse T-cell hybridomas specific for each protein did not cross-react with heterologous peptides.
Our results demonstrated for the first time that ESAT-6- and CFP-10-specific Th1, Th22 and Th17 cells existed in the patients with TBP and might play an essential role against M. tuberculosis infection.
The sensitivity of the IgG test ranged from 69.4% (ESAT-6) to 77.6% (ESAT-6/14KD/38KD) in the active TB patients; the specificity of assays varied from 78.4% (CFP-10) to 90.2% (14KD+38KD) in the healthy control groups.
CTL immunogenicity of Rv3615c antigen and diagnostic performances of an ESAT-6/CFP-10/Rv3615c antigen cocktail for Mycobacterium tuberculosis infection.
These results suggest that serum CFP-10 quantitation holds great promise for the rapid diagnosis of suspected TB cases in patients who are HIV-infected.
Although BfrB is not as immunodominant as ESAT-6/CFP-10 during acute M.tb infection, comparable BfrB-specific cellular immune responses are observed in LTBI population with the potential to increase the sensitivity for LTBI screening.