Impaired systemic cell-mediated immunity and increased susceptibility to acute respiratory tract infections in patients with COPD

SummaryAlthough it has been reported that chronic obstructive pulmonary disease (COPD) is frequently associated with systemic immune disturbances, negative impact of these disturbances on the increased prevalence of acute respiratory tract infections (aRTIs) has remained unclear. We evaluated circulating levels of interferon-γ (IFN-γ), soluble interleukin-2 receptor (sIL-2R), neopterin, and soluble intercellular adhesion molecule-1 (sICAM-1) in 35 clinically stable patients with COPD and in 22 age-matched healthy controls, since these molecules are considered to reflect the in vivo status of systemic cell-mediated immunity (CMI). We found that circulating levels of sIL-2R (1.52±1.25 vs. 0.97±0.48ng/ml; P<0.05), neopterin (7.23±4.24 vs. 4.95±1.52nmol/l; P<0.05), and sICAM-1 (665±302 vs. 328±164ng/ml; P