Ex vivo characterization of early secretory antigenic target 6-specific T cells at sites of active disease in pleural tuberculosis.
Wilkinson KA., Wilkinson RJ., Pathan A., Ewer K., Prakash M., Klenerman P., Maskell N., Davies R., Pasvol G., Lalvani A.
Presence of early secretory antigenic target-6 (ESAT-6)-specific, interferon- gamma -secreting T cells in blood accurately marks tuberculosis infection. In tuberculous pleural effusions from 10 patients with tuberculosis, these cells were concentrated a mean of 15-fold (standard deviation, +/-6-fold), relative to their level in peripheral blood (P=.014), and displayed rapid effector function. Such cells were absent in 8 control patients with nontuberculous pleural disease. The recruitment of ESAT-6-specific T cells to inflamed tuberculous tissue demonstrates their function in vivo and suggests a novel way to diagnose tuberculous pleuritis.