NLRP3炎性小体在急性胰腺炎中的表达及临床意义

Expression and clinical significance of NLRP3 inflammasome in patients with acute pancreatitis

为探讨核苷酸结合寡聚化结构域样受体蛋白3(nucleotide-binding oligomerization domain-like receptors family pyrin domain containing 3,NLRP3)炎性小体在急性胰腺炎(acute pancreatitis,AP)中的表达及临床意义,以160例AP患者为研究对象,按AP病情严重程度分为轻症AP(mild AP,MAP)组(52例)、中度重症AP(moderately severe AP,MSAP)组(50例)和重症AP(severe AP,SAP)组(58例);根据患者临床结局,分为存活组(135例)和死亡组(25例)。采用RT-PCR、Western blotting检测各组PBMC中NLRP3、Caspase-1 mRNA及相关蛋白表达,ELISA检测相关细胞因子(IL-1β、IL-18)水平,分别比较各组指标的差异,评价NLRP3水平对AP患者病情严重程度的预测价值。结果显示,不同严重程度AP组间外周血NLRP3 mRNA及蛋白表达,Caspase-1 mRNA及Cleaved-Caspase-10、Cleaved-Caspase-20蛋白表达,外周血IL-1β、IL-18水平比较,差异具有统计学意义(P<0.05)。其中SAP组上述指标水平最高,MSAP组次之,MAP组最低。死亡组患者NLRP3、Caspase-1 mRNA表达水平及外周血IL-1β、IL-18水平明显高于存活组(P<0.05)。AP患者PBMC NLRP3 mRNA表达与Caspase-1 mRNA、外周血IL-1β和IL-18水平呈正相关(r=0.742,P=0.000;r=0.610,P=0.015;r=0.570,P=0.019),与AP病情严重程度评分[修正CT严重指数(modified CT severity index,MCTSI)评分、Ranson评分及急性生理与慢性健康评估(acute physiology and chronic health evaluation,APACHEⅡ)评分]呈正相关(r=0.705,P=0.004;r=0.690,P=0.006;r=0.638,P=0.012)。受试者工作特征(receiver operating characteristic,ROC)曲线分析显示,NLRP3 mRNA的AUC为0.851[95%可信区间(confidence interva,CI)0.778~0.923],其最佳工作点为2.25,此时预测AP患者病情严重程度的敏感性和特异性分别为76.00%和85.71%,均显著优于IL-1β和IL-18。NLRP3参与了AP患者的机体炎症反应,在对AP患者病情严重程度的预测方面具有一定的应用价值。

To study the expression and clinical significance of nucleotide-binding oligomerization domain-like receptors family pyrin domain containing 3(NLRP3)inflammasome in patients with acute pancreatitis(AP),160 patients with AP were divided into mild AP(MAP)group(52 cases),moderately severe AP(MSAP)group(50 cases)and severe AP(SAP)group(58 cases)according to the severity of AP,and survival group(135 cases)and death group(25 cases)according to the clinical outcome.The mRNA and protein levels of NLRP3 and Caspase-1 in PBMC were measured by RT-PCR and Western blotting.The levels of related cytokines(IL-1β,IL-18)were detected by ELISA.The differences of the above indicators among different groups were compared and the predictive value of NLRP3 regarding the severity of disease was evaluated.The results showed that the mRNA and protein levels of NLRP3,the mRNA levels of Caspase-1 and the protein levels of Cleaved-Caspase-10 and Cleaved-Caspase-20,and the levels of IL-1β,IL-18 in peripheral blood in different severity groups were significantly different(P<0.05).Among them,the levels of the above indicators in the SAP group were the highest,followed by the MASP group,and with the MAP group were the lowest.The levels of NLRP3,Caspase-1 mRNA and IL-1β,IL-18 in peripheral blood in the death group were significantly higher than those in the survival group(P<0.05).The expression of NLRP3 mRNA in PBMC of AP patients was significantly positively correlated with Caspase-1 mRNA,IL-1βand IL-18 in peripheral blood(r=0.742,P=0.000;r=0.610,P=0.015;r=0.570,P=0.019);meanwhile,there was a significant positive correlation with severity score of AP[modified CT severity index(MCTSI)score,Ranson score and acute physiology and chronic health evaluation(APACHEⅡ)score](r=0.705,P=0.004;r=0.690,P=0.006;r=0.638,P=0.012).Receiver operating characteristic(ROC)curves analysis showed that the AUC of NLRP3 was 0.851[95% confidence interva(CI)0.778-0.923],and the optimal operating point was 2.25,which had 76.00% sensitivity and 85.71% specificity in predicting the severity of AP patients,indicating ROC curves analysis was better than IL-1β and IL-18 level determination.Together,NLRP3 is involved in the inflammatory response in patients with AP and there is certain application value for predicting the severity of AP patients.