Comparative characteristics of TRP channels expression levels on the macrophages of patients with chronic obstructive pulmonary disease

Introduction. Macrophages are one of the key cells in the pathogenesis of chronic obstructive pulmonary disease (COPD), mediating the primary immune response and coordinating the further reaction of the immune system upon contact with cigarette smoke and air pollutants. It is known that some TRP channels expressed on macrophages are receptors for dust particles and cigarette smoke components.Aim. To study the features of TRPV1, TRPV4, TRPA1 and TRPM8 channels expression on monocyte-derived macrophages and alveolar macrophages of COPD patients and smokers without bronchial obstruction.Materials and methods. Expression of TRP channels at the mRNA level was studied in monocyte-derived macrophages obtained from 8 COPD patients and 6 healthy smokers by quantitative reverse transcription PCR. Expression of TRP channels at the protein level was studied on alveolar macrophages of 39 COPD patients and 8 healthy smokers by indirect flow cytometry.Results. It was found that under in vitro conditions, monocyte-derive macrophages of COPD patients were distinguished by a significant 4.8-fold increase in the number of TRPV1 transcripts (p=0.009). At the same time, the expression of the TRPV1 protein on the alveolar macrophages of COPD patients was also significantly higher when compared to the cells of smokers from the control group (14.1 [6.4‒21.2]% vs. 6.1 [2.1‒9.8]%, p=0.006). In addition, we found that TRPV4 expression was increased among active smokers with COPD, and the expression of TRPA1 and TRPM8 channels correlated with some lung function parameters.Conclusion. The obtained results suggest that the increased expression of TRPV1 on macrophages may be a marker of the disease and contribute to its development, while the expression of TRPV4, TRPA1 and TRPM8 may influence the clinical course of COPD.