Expression Of Serum Cytokines Of Coal Workers, Pneumoconiosis (CWP) And The Prediction Role In CWP In Early Period

Objectives To explore sensitive and specific index for early recognition and diagnosespneumoconiosis, ROC curves of cytokines, including tumor necrosis factor-α(TNF-α),connective tissue growth factor(CTGF), platelet-derived growth factor(PDGF), monocytechemokin protein-1(MCP-1) and interleukin-8(IL-8) were constructed. Values of thecytokines were screened on the basis of different serum levels of pneumoconiosis at stageΙ, suspected silicosis patients, healthy silica dust-exposure workers and healthy controls,so as to provide new method for early detection of coal workers’pneumoconiosis.Methods90cases of pneumoconiosis at stage Ι,180suspected silicosis patients withsmall shadow,180healthy silica dust-exposure workers with completely normal chestradiograph matched the suspected silicosis patients by age and161healthy controls notengaged in dust-exposed chosen from Occupational Disease Prevention Hospital ofQianjiaying were diagnosed by the qualified doctor on the basis of the diagnostic criteriaof Pneumoconiosis (GBZ70-2009). Laboratory studies, in the context of informedconsent5ml median cubital vein blood were drawn from subjects on an empty stomach.After1~2h stewing, the blood were centrifuged at2000r/min for10min. The serum werestored at-80℃and discarded hemolysis. In strict accordance with the manual operationof MCP-1, IL-8, TNF-α, CTGF and PDGF Elisa kit to detect the expression levels ofcytokines with BioTek microplate reader. Data were input by Microsoft Excel2007andanalyzed by SPSS13.0software. The quantitative data from a normal distribution, such asage, dust exposure, level of cytokine expression use analysis of covariance and stratifiedanalysis and two categories of qualitative data such as smoking rate analysis use thechi-square test. Evaluate the advantages and disadvantages of screening by ROC curveson the basis of the gold standard of X-ray.Results1Average age of control group was (27.4±5.0) years old, age of silica dustworkers, suspected silicosis patients, stage Ι pneumoconiosis patient were (43.4±10.7),(48.2±6.2) and (64.7±7.0) years old respectively. The duration of dust exposure was(19.5±11.5),(22.4±9.9) and (28.3±7.2) years respectively. The difference of smokingrates and jobs were not statistically significant (P>0.05). Age and dust exposure length ofservice were statistically significant (P<0.05).2Expression of five cytokine levels in fourgroups and the influence on the expression of cytokine levels with length of serviceshowed that whether it is smoking or non-smoking, the expression level of five cytokines in stage Ι pneumoconiosis patients were significantly higher than those in suspectedsilicosis patients, the exposed group and the healthy control group (P<0.05); Whether it issmoking or non-smoking the expression level of five cytokines in suspected silicosispatients significantly higher than the healthy control group (P<0.05) and the expressionlevel of IL-8in suspected silicosis patients significantly higher than those in the exposedgroup (P<0.05); The expression level of five cytokines in the exposed group whosmoking significantly higher than the healthy control group (P<0.05); The expressionlevel of L-8, MCP-1, TNF-α, PDGF in the exposed group who non-smoking significantlyhigher than the healthy control group (P<0.05). The expression level of MCP-1, IL-8,TNF-α, CTGF and PDGF gradually increased from healthy controllers to stage Ιpneumoconiosis patients, the same trend also showed with age goes by(P<0.05).3Thevalue of different cytokine expression levels screening CWP. With their ROC curveabove the reference line, there was statistical significant in area under the curve (AUC) ofIL-8, MCP-1, TNF-α, CTGF, PDGF between two groups; The best critical value of5cytokines were1870.38pg/ml,988.22pg/ml,38.77ng/ml,1730.82pg/ml and178.06ng/mlrespectively. With their cut off points, TNF-α was the highest sensitivity (92.2%), thelowest missed rate (7.8%), the lowest negative likelihood ratio (0.08) and the highestnegative predictive value (98.0%); MCP-1was the highest specificity (97.8%), thehighest Youden index (87.8%), the lowest rate of misdiagnosis (2.2%), the highestpositive likelihood ratio (40.91), the highest consistency rate (96.2%), the highestpositive predictive value (91.0%); The Kappa value of these indexes was between0.41and0.88and MCP-1was the highest Kappa value0.88.Conclusions1The expression level of MCP-1, IL-8, TNF-α, CTGF and PDGFgradually increased from healthy controllers to stage Ι pneumoconiosis patients, the sametrend also showed with age goes by.2Results of ROC curve analysis and screeningevaluation showed that IL-8, MCP-1and TNF-α can be used as CWP screening earlyindicators, and the best critical value was1870.38pg/ml,988.22pg/ml and38.77ng/mlrespectively.