ASPETTI IMMUNOLOGICI DELLA BRONCOPNEUMOPATIA CRONICA OSTRUTTIVA E CORRELAZIONI CON IL FENOTIPO CLINICO DI MALATTIA

Chronic Obstructive Pulmonary Disease (COPD) is a chronic inflammatory lung disease that, slowly and progressively, lead to obstruction of the airways, thus increasing resistance to the air flow. Both innate and adaptive immunity contribute to the chronic inflammatory process, with the bronchial walls of the small airways being the most involved site. This study aims to identify changes in innate immunity in healthy smokers and COPD patients to better understand its role in the onset and progression of the disease. Previous data from several studies showed that the immune response is altered in subjects chronically exposed to cigarette smoke, promoting chronic inflammation. NK cells are cytotoxic lymphocyte critical to the innate immune system. Through immunohistochemical analysis, we investigated for the first time NKp46+ cells expression in lung tissue biopsies obtained from patients with COPD, unobstructed smokers and unobstructed non-smokers. With the same method, we evaluated the expression of the transcription factor IRF3 and the cytoplasmic receptor MDA-5, which play a crucial role for an effective antimicrobial response as two major component of the interferons pathway. Our results shows an increased expression of NKp46+ cells and higher levels of IRF3 and MDA-5 in the group of subjects with COPD.