Following anti-TB therapy, CD27<sup>low</sup>IFN-γ<sup>+</sup> cells decline parallel to reduction/repair of lung destruction.

<p>A, Percentages of CD27<sup>low</sup>IFN-γ<sup>+</sup> cells were determined at the start of treatment and two months later. Depending on the results of “IFN-γ/CD27” assay, patients were divided into three groups: in “CD27<sup>low</sup>- high” group, initially elevated percentages of CD27<sup>low</sup>IFN-γ<sup>+</sup> cells did not decline following 2-mo therapy; in “CD27<sup>low</sup> – reduced” group, percentages of CD27<sup>low</sup>IFN-γ<sup>+</sup> cells declined to become below the 47% threshold, but remained above 35.1% threshold (upper limit of norm); in “CD27<sup>low</sup> - normalized” group, percentages of CD27<sup>low</sup>IFN-γ<sup>+</sup> cells declined to become below the 35.1% threshold. Dotted lines show 35.1 and 47% thresholds. B–D, diagrams showing changes in lung destruction (B), sputum <i>Mtb</i>-positivity (C) and clinical TB severity (D) for each group of patients following 2-mo therapy. Closed segments, no improvement; squared segments, reduction of lung destruction, clinical symptoms or numbers of <i>Mtb</i> in the sputum; open segments, normalization (repair of lung destruction, conversion of sputum assay, disappearance of intoxication symptoms), striped segments – no abnormalities at the start of the treatment.</p>