IFNG and tuberculosis: The IFN-γ, CXCL10 and TNF-α in response to ESAT-6 and PPD did not differentiate between LTBI (S2) and active TB in our study while significantly differential levels of the cytokines in addition to sIL2ra and MDC were detected in sera between active TB patients and individuals with TST+[24], which indicates that multiplex analyses using many more cytokines in serum or culture supernatant would be of great benefit to more comprehensive biosignature for differential diagnosis of LTBI versus active TB.