The role of the microbiota components in modification of the immune response in some cases of chronic obstructive pulmonary disease

Abstract

Background. According to the World Health Organization, chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality in the world. COPD with frequent exacerbations is a most challenging variant of the disease. Currently it is not clear how respiratory microbiota can modify the immune response in this disease. Aim. To establish the role of bacterial oligonucleotides in modification of the immune response in patients with COPD. Materials and м ethods. In accordance with the protocol of the study, 10 patients with stable COPD with frequent exacerbations and 10 patients without frequent exacerbations were included. Immature dendritic cells were obtained by culturing the monocyte fraction of the peripheral blood of patients with COPD. The cells were stimulated by addition of bacterial lipopolysaccharide and small oligodeoxynucleotides (CpG-ODN) of A or B classes. Then the immunophenotypical profile of the obtained cells was determined by flow-cytometry with the use of monoclonal antibodies to antigens CD40, CD83, CD86. To determine the antigen-presenting properties, these dendritic cells were cultivated with CD4+, and then the phenotypic profile of the obtained T-lymphocytes was evaluated by using antibodies to CD4, CD25, CD127, and CD45RO. Results. Cultivation of stimulated dendritic cells by СpG-ODN of A class with T-cells in COPD patients without exacerbations leads to an increase of the amount of lymphocytes of CD25+CD45RO phenotype (15% increase after stimulation), in contrast to the group of patients with frequent exacerbations of COPD (p = 0,018). It may indicate inadequate control of persistent inflammation, mediated by CD25+CD45RO pool of cells in the group of COPD patients with frequent exacerbations. Conclusion. This study demonstrated the presence of discoordination of the immune response of a bidirectional nature in patients with COPD with frequent and infrequent exacerbations.