In the literature, it has also been reported that higher numbers of alveolar macrophages can augment levels of HMGB1 in BAL fluid (BALF) from smokers with COPD, and these data are in accordance with Hou C. et al., who reported that macrophage numbers correlated positively with levels of HMGB1 in the sputum of patients with COPD [39,40]. The gene discussed is HMGB1; the disease is chronic obstructive pulmonary disease.