Fig. 2

Assessment of eight candidate diagnostic antigens. a A total of 54 serum samples including 25 random latently TB-infected serum samples, 15 active infection samples and 14 healthy controls were used for detection. Red, blue and green dots represent serum samples in the LTBI, active TB and healthy control groups recognized by antigens, respectively. b The sensitivities and specificities of variable combinations of proteins (range 2–6 proteins) were calculated using the caret package in R statistical software. Each dot represents one combination (combinations with identical sensitivities and specificities are overlapping). Combinations with higher sensitivities and specificities (>0.7 and >0.8, respectively) to distinguish LTBI from healthy controls are marked with red dots. RLU = relative light units