Role Of IFN-? And IL-4 In Chronic Obstructive Pulmonary Disease

Background Chronic obstructive pulmonary disease?COPD?is an inflammatory disease characterized by airflow limitation that is not fully reversible.Because of the complexity of COPD,investigating thepathogenesisof COPD may provide new approaches for individualized diagnosis and therapies.Previousresearchinanimals and clinical research fund that the Th1/Th2unbalance played an important role in the pathogenesis of COPD.What's more,there was a predominanceof Th1 in stable COPD.Th1 cells typically produce cytokines such as interferon-??IFN-??,interleukin-1?IL-1?,and interleukin-2?IL-2?,which are involved in cellular defence mechanisms in response to infection.Studies advocate that Th2 cells are characterized by their expression of IL-4,IL-6,and IL-13,which mediate allergic inflammation.In physiological conditions,there is a dynamic balance between immune responses of Th1 and Th2 cells,and when this balance is disturbed,we call it Th1 superiority or Th2 superiority.It has been found that COPD is a hyperfunctional subgroup of Th1 type cells.Objective To compare lung respiratory function index,blood gas index,the level of IFN-?and IL-4 in venous blood in different groups of subjects,to analyze the correlation between lung ventilation index and the level of IFN-?and IL-4 in the venous blood,and explore the effects of IFN-?and IL-4 on the respiratory function of COPD.Methods This study includes two aspects of clinical research and animal experiments.The clinical study of COPD patients?COPD group?and Healthy People?control group?as the study subjects.In animal experiments,COPD rats?COPD Group?and Healthy Rats?control group?were studied.The COPD rats were treated with passive smoking combined with lipopolysaccharide in the trachea.That is to say,rats were placed in a 50 cm×30 cm×50 cm smoking exposure box for 30 min twice daily for 90consecutive days(each lighted 8 cigarettes in each box,On the 3th day and 60th day LPS was substituted for passive smoking and instilled intratracheally at a dose of 250ug·kg-1.Rats in the control group did not smoke,At the same time,the lipopolysaccharide was replaced with the same dose of physiological saline.The following operations were performed in both clinicalresearch and animal experiment:1.Detecting arterial partial pressure of oxygen?PaO₂?,arterial blood carbon dioxide partial pressure?PaCO2?,and arterial bloodoxygen saturation?SaO2?.2.Measuring lung function:the forced expiratory volume in one second?FEV1?,forced vital capacity?FVC?,FEV1/FVC.3.The levels of IFN-?and IL-4 in peripheral blood were measured by a double-antigen sandwich ELISA.4.Comparing the relationship:FEV1 and FEV1/FVC with IFN-?,FEV1 and FEV1/FVC with IL-4.Using T-Test to compare the above results in group,the correlation between FEV1 and FVC with IFN-?,and the correlation between FEV1 and FVC with IL4 were used by the rank correlation analysis.Results The results have a very visible degree of uniformity between clinical research and animal experiment.The results are asfollows:1.PaO₂ and SaO₂ in COPD group were lower than that in control group,but PaCO₂ in COPD group was higher than that in control group.2.Measuring pulmonary ventilation function:FEV1 and FEV1/FVC in COPD group were less than those in control group.3.The level of IFN-?in peripheral blood in COPD group were significantly higher than that in control group,the level of Il-4 in peripheral blood in COPD group were significantly lower than that in control group.4.The FEV1 and FEV1/FVC in COPD group were negatively correlated with the levels of IFN-?,and positively correlated with the levels of IL-4.Conclusion 1.The negtive correlation between FEV1,FEV1/FVC and IFN-?in COPD group,the higher the level of interferon gamma,the worse the respiratory function.2.The positive correlation between FEV1,FEV1/FVC/FVC and IL-4 in COPD group,the higher the level of IFN-?,the worse the respiratory function.