TABLE 6.

IFN-γ or PBMC proliferation induced in response to M. tuberculosis-specific antigens^a

Subject condition	Mean assay result ± SEM (no. of subjects)
	Q-TB in-tube (IU/ml)	Q-TB(IU/ml)		Diluted whole blood with proteins (IU/ml)	Whole-blood intracellular staining (% IFN-γ-positive cells)		PBMC-cytokine with proteins (IU/ml)	PBMC-proliferation with proteins (SI)
		Peptides	Proteins		Proteins	Peptides
Active tuberculosis	108.8 ± 91b (17)	24.1 ± 16.3c (18)	2.3 ± 0.8d (17)	30.0 ± 24.1e (17)	0.1 ± 0.04f (17)	0.3 ± 0.1g (18)	10.8 ± 4.8h (11)	35.1 ± 12.3i (15)
BCG unvaccinated	0.1 ± 0.03 (13)	0.02 ± 0.01 (13)	0.08 ± 0.04 (10)	0.2 ± 0.1 (13)	0.01 ± 0.01 (13)	0.01 ± 0.01 (14)	0.02 ± 0.01 (11)	1.4 ± 0.21 (12)

^aThe proteins were ESAT-6 and CFP-10, and the peptides were ESAT-6 and CFP-10 overlapping peptides. IFN-γ was measured by ELISA and is expressed as IU/ml or was measured by intracellular staining and is expressed as the percentage of positive cells. Lymphocyte proliferation was measured by [³H]thymidine incorporation and is expressed as the SI. The differences between the two groups of subjects were assessed by the Mann-Whitney U test.

^bP = 0.009 compared with the results for the BCG-unvaccinated controls.

^cP = 0.001 compared with the results for the BCG-unvaccinated controls.

^dP < 0.001 compared with the results for the BCG-unvaccinated controls.

^eP = 0.007 compared with the results for the BCG-unvaccinated controls.

^fP = 0.004 compared with the results for the BCG-unvaccinated controls.

^gP < 0.001 compared with the results for the BCG-unvaccinated controls.

^hP = 0.006 compared with the results for the BCG-unvaccinated controls.

ⁱP < 0.001 compared with the results for the BCG-unvaccinated controls.