Associations between Indicators of Nitrosative Stress and Levels of soluble HLA-I, CD95 Molecules in Patients with COPD

At the present stage of study of chronic obstructive pulmonary disease (COPD) one of the problem is the definition of new criteria for the topical and systemic chronic inflammation of this disease. The aim of the research was to study the concentration of nitric oxide metabolites, the level of soluble human leukocyte antigens class I (sHLA-I) and of soluble CD95 molecules (sCD95) in the serum of blood and exhaled breath condensate (EBC) in patients with exacerbation of COPD. We investigated 49 moderate-to-severe COPD patients with exacerbation, and 21 healthy nonsmokers. The concentration of sHLA-I and sCD95 molecules was studied in serum and in EBC using the ELISA method. The nitrosative stress was evaluated by the measurement of NO2-levels in the serum and the concentration of Sigma NO2-/NO3_- in the EBC. Exacerbation of COPD is associated with increasing concentrations of NO2- in the serum and of the levels of Sigma NO2-/NO3- in the EBC, together with the changing concentration of sHLA-I and sCD95 molecules in the both biological liquid. An association was discovered between the exacerbation of COPD and the indicators of nitrosative stress, the parameters of lung function and the concentration of sHLA-I, sCD95 molecules. The findings suggest a pathogenetic role of nitrosative stress and of soluble molecules of HLA-I and CD95 in the progression of COPD. The studied markers can be used as predictors of unfavourable prognoses of COPD and as quantitative criteria in the diagnosis of exacerbation of moderate-to-severe COPD.