Tobacco smoke suppresses T cells but not antigen-presenting cells in the lung-associated lymph nodes.

Chronic inhalation of cigarette smoke in mice preferentially inhibited the antigen-specific T-cell proliferative response of lung-associated lymph nodes compared to anatomically distant lymph nodes. Cell mixing experiments demonstrated that the defect in smoked mice resulted from an abnormality in T-lymphocyte function. In contrast, the activity of antigen-presenting cells was similar in smoked and sham-smoked control animals. These results suggest that T-cell function in lung-associated lymphoid tissue may be inhibited in smokers, leading to a localized predisposition to respiratory tract infections.