Figure 3. Significantly fewer tuberculin-reactive CD4 T-cells express CD27 in TB-patients than in controls.

Proportions of CD27-positive and negative cells were based on a minimum of 50 IFN-γ positive events. Vertical numbers indicate evaluated events (median and range). Controls included unexposed controls, professionally TB-exposed health care workers, and donors with latent infection. A threshold of 49% would effectively discriminate between patients and controls (dotted line). Controls with latent TB infection had higher values than individuals with no known exposure to TB.