Association Analysis Between Serum Inflammatory Factor IL-32, Hs-CRP, PCT And COPD Phenotypes

Objective:Chronic obstructive pulmonary disease(COPD) is a common and frequently encountered respiratory disease, whose morbidity and mortality are steadily rising in the world and is a challenge for human. The heterogeneity of pathogenesis and phenotypic identification play a significant role in individualized treatment. Inflammatory process is recognized as the main pathogenic mechanism, and no matter in the local or systemic inflammation, inflammatory cytokines are involved in and play an important role. Interleukin-32(IL-32), defined as a novel pro-inflammatory cytokine, participates in the progression of COPD, and its high level is closely related to COPD. Hypersensitive C-reactive protein(Hs-CRP) and procalcitonin(PCT) are clinical commonly used biomarkers that reflect systemic inflammatory conditions, which are used to evaluate condition and guide treatment. In the study, we respectively divide the patients into different courses(acute exacerbation, stable stage), different combined assessment groups(group A,B,C,D) and different HRCT based phenotypes(bronchitis type, emphysema type, mixed type), Through the detection of IL-32, Hs-CRP and PCT and the association analysis, providing a new insight into the heterogeneity and individualized treatment.Methods:1 SubjectsSelected outpatients diagnosed COPD and healthy volunteer for medical examination in the Second Hospital of Hebei Medical University from January, 2014 to January, 2015. The diagnosis of COPD accords to the COPD treatment guidelines of 2013 revised by the 2013 Chinese Medical Breathing Branch of COPD group. A total of 70 COPD patients(50 male,20 female, average age 65.11±9.54 years), and 12 healthy volunteers(5 male,7 female, average age 69.00±3.19 years) were included in the study. And there were no significant differences in their age and gender(P > 0.05). Patients with pneumonia,other parts of bacterial infections, asthma, bronchiectasis, serious pneumothorax, ctive tuberculosis, and combined cardiovascular disease, cerebrovascular disease, kidney, blood and autoimmune system diseases, or accepted anti-infection therapy more than 5 days in other hospitals were excluded from the study.On the day visiting the pulmonology outpatient services, the patients accepted a chest high-resolution computed tomography(HRCT) scan and Hs-CRP examination, and accepted pulmonary function tests if allowed(the severe patients accepted pulmonary function tests a few days later if condition improved). According to acute exacerbation and remission criteria of COPD which was raised by Anthonisen, the patients were divided into: ①COPD exacerbations: 29 male, 13 female, average age 67.36±9.62 years; ②Stable stage: 21 male, 7 female, average age 61.75±8.50 years. And according to the COPD treatment guidelines of 2013, patients were divided into: ①group A:low-risk, less symptoms: 11 male, 4 female, average age 63.53±6.44 years;②group B:low-risk, more symptoms: 9 male, 5 female, average age 65.14±8.89 years; ③group C:high-risk, less symptoms: 10 male, 4 female, average age 56.64±7.92 years; ④group D:high-risk, more symptoms: 20 male, 7 female, average age 70.37±8.92 years. And according to the HRCT patients were divided into: ①emphysema type: 20 male, 2 female, average age 64.91±9.31 years; ②bronchitis type:14 male, 12 female, average age 65.85±11.94 years; ③mixed type: 16 male, 6 female, average age 64.45±7.69 years.Select inpatients who diagnosed lung cancer and accepted surgical treatment in the chest surgery of Hebei Province General Hospital from January, 2014 to January, 2015, and there were 16 male, 2 female, average age 60.09±12.71 years, and all the patients accepted lung HRCT, pulmonary function tests, arterial blood gas measurement, and routine blood tests. And patients were divided into: ①health current smoker: with normal pulmonary function, smoke, 6 male, 0 female, average age 52.67±9.50 years; ②health non smoker: with normal pulmonary function, never smoke, 4 male, 2 female, average age 69.25±8.96 years; ③COPD current smoker: conform to the diagnostic criteria of COPD, FEV1%FVC<70%, smoke, 6 male, 0 female, average age56.50±14.6 years.2 Specimen collectionBlood was collected from cubital vein on fasting, then was injected into dry vacuum non-anticoagulant tube, centrifuged 5minutes by 4000r/min. Serum was collected into EP tubes, then saved in the-70 ℃refrigerator after signed, and waiting for detection for the levels of IL-32 and PCT.Blood was collected from cubital vein on fasting, then was injected into EDTA anticoagulant tube, immediately examined the levels of Hs-CRP by immunochromatographic method.Normal lung tissue at least 2cm far away from the canceration was collected when undergoing surgery, then collected the supernatant after homogenated. The serum of those patients was also collected, the method was the same as described above, then stored the supernatant and serum at-70 ℃refrigerator for subsequent analyses.3 Quantification of IL-32, PCT and Hs-CRPIL-32 levels in serum and supernatant, and PCT levels in serum were quantified by ELISA according to the manufacturer’s instructions. Hs-CRP levels in whole blood were quantified by immunochromatographic method according to the manufacturer’s instructions.The minimum detectable concentration of IL-32 is less than 15pg/ml.The normal reference value of Hs-CRP is less than 5 mg/L, greater than 5 mg/L is abnormal; and the normal reference value of PCT is less than 0.05 mg/ml, greater than 0.05 mg/ml is abnormal, 0.05-0.5ng/ml reminders local infection, 0.5-2ng/ml reminders the increased incidence of serious bacterial infection or sepsis.Results:1 The level of IL-32 in serum and supernatant in COPD were higher than that in healthy control group which included health current smoker and health non smoker(P<0.05); The level of IL-32 in serum and supernatant in health current smoker were higher than that in health non smoker(P<0.05); The level of IL-32 in supernatant in COPD and health current smoker were higher than that in serum(P<0.05).2 The level of serum IL-32 in AECOPD and stable patients were higher than that in healthy control group(P<0.05); The level of serum IL-32 in AECOPD were higher than that in stable group(P<0.05).3 The level of serum IL-32 in group A, group B, group C and group D were higher than that in healthy control group(P<0.05); group D was higher than those in group A, group B and group C(P<0.05); but there were no significant differences among the other groups(P>0.05).4 The level of serum IL-32 in emphysema type and mixed type were higher than that in bronchitis type(P<0.05); but there was no significant difference between emphysema type and mixed type(P>0.05).5 The level of Hs-CRP and PCT in AECOPD were higher than that in stable patients and healthy control group(P < 0.05); but there was no significant difference between stable patients and healthy control group(P>0.05).6 The level of Hs-CRP in group A,B,C and D were higher than that in control(P<0.05), group D was higher than those in group A, group B and group C(P<0.05), but there were no significant differences among the other groups(P>0.05); the level of PCT in group D was higher than those in group B and control(P<0.05), there were no significant differences among the other groups(P>0.05).7 The level of Hs-CRP in mixed type, bronchitis type and emphysema type were higher than that in health control group(P<0.05), the mixed type was higher than that in bronchitis type and emphysema type(P<0.05), and the bronchitis type was higher than that in emphysema type(P<0.05); the level of PCT in bronchitis type and mixed type were higher than that in emphysema type and health control group(P < 0.05), but there was no significant difference between bronchitis type and mixed type(P>0.05), and there was no significant difference between emphysema type and health control group(P>0.05).8 The level of serum IL-32 in COPD was negatively correlated with FEV1%pre(r=-0.414, P<0.05); The level of serum IL-32 in COPD was positively correlated with RV%TLC(r=0.311, P < 0.05); There were no correlation between serum IL-32 and Hs-CRP、PCT(P>0.05); There were no correlation between serum Hs-CRP, PCT and FEV1%pre(P>0.05).Conclusions:IL-32 participates in the occurance and progression of COPD, which is positively correlates with the degree of airflow obstruction and emphysema. The up-regulation and high-expression of pro-inflammatory cytokines has a close relationship with COPD, and IL-32 with its signaling mechanism maybe become the heterogeneity and potential target of individualized treatment. Hs-CRP and PCT, as non-specific inflammatory index, may indicate the acute exacerbation and guide antibiotic therapy in the acute exacerbation to some extent; but there is no correlation between their high-expression and airflow obstruction, and their sensitivity or specificity neither response the heterogeneity nor used for guiding individualized treatment.