Table 3.

Immunological activities of the purified CFPs in M. tuberculosis-infected mice and guinea pigs

ProteinIFN-γ release (ng/ml)aDTH reaction diam (mm)b
Controlc <0.10 ± 0.0<3 ± 0.3
PPD/ST-CFd 20.96 ± 1.111.7 ± 0.5
CFP179.25 ± 0.112.9 ± 1.0
CFP202.39 ± 1.812.3 ± 0.8
CFP2110.73 ± 0.0410.4 ± 0.5
CFP22/255.34 ± 0.34.2 ± 0.2
rCFP22<0.10 ± 0.0<3 ± 0.2
rCFP259.87 ± 0.110.3 ± 0.6
CFP282.82 ± 0.25.8 ± 0.8
  • a IFN-γ release from memory effector cells was measured in spleen cell cultures isolated from three memory-immune C57BL/10 mice 4 days after rechallenge with 106 CFU of M. tuberculosis. The proteins were used at 2 μg/ml. Results are means ± standard errors.

  • b Skin testing was done 4 weeks after infection with 5 × 104 CFU of M. tuberculosis. Values shown are means ± standard errors; for eight readings. The proteins were tested at 1 μg/ml.

  • c Stimulation without antigen.

  • d PPD (10 tuberculin units) was used in the skin test experiment, while ST-CF (5 μg/ml) was used in the lymphocyte cultures.