慢性乙型肝炎患者外周血Th17细胞比例和IL-17表达水平的临床意义

目的分析临床不同疾病程度慢性乙型肝炎(CHB)患者和正常对照者外周血辅助性T细胞17(Th17)的比例和其效应分子白细胞介素17(IL-17)水平的变化与疾病严重程度、乙型肝炎病毒(HBV)DNA载量、肝脏损伤标志物等的关系,以进一步证实Th17细胞在CHB患者疾病进程中的作用。方法应用流式细胞术、实时荧光定量聚合酶链反应(PCR)和酶联免疫吸附试验(ELISA)等检测93例CHB患者(其中轻度21例、中度37例、重度35例)和28名正常对照者外周血Th17细胞比例、血清IL-17水平,纯化CD4+T细胞经功能性抗CD3、抗CD28抗体刺激后IL-17和维甲酸相关孤儿核受体C(RORC)mRNA表达水平,纯化CD4+T细胞刺激后培养液中IL-17水平。比较和分析上述检测数据在各组间的统计学差异及与HBV DNA载量、肝脏损伤标志物等的关系。结果与正常对照组相比,CHB组外周血Th17细胞比例明显升高,且随着疾病的加重,Th17细胞的比例也随之上升。CHB重度组Th17细胞比例、IL-17和RORC mRNA表达水平显著高于中度组、轻度组和正常对照组(P0.05),各组间血清IL-17水平差异无统计学意义(P0.05);CHB组纯化CD4+T细胞刺激后培养液中IL-17水平显著高于正常对照组(P0.05);CHB重度组培养液IL-17水平明显高于中度组和轻度组(P0.05)。CHB组外周血Th17细胞比例与血清丙氨酸氨基转移酶(ALT)水平呈明显正相关(P0.01),而与血清HBV DNA载量无相关性。结论 CHB患者体内增高的Th17细胞可能是造成肝脏炎症、肝细胞损伤的主要原因之一,并与CHB的重症化密切相关。

The proportion of Thl7 cells and IL-17 expression levels in peripheral blood of patients with chronic hepatitis B and their clinical significance

Objective To analyze T helper 17 （Thl7） cell proportion and interleukin 17 （IL-17） levels in peripheral blood of patients with chronic hepatitis B （CHB） and healthy controls, and to evaluate their correlations with disease severity, serum hepatitis B virus（HBV） DNA load and liver injury markers, in order to investigate Thl7 cells＇ role in the pathogenesis of CHB. Methods The Thl7 cell proportion and IL-17 levels in peripheral blood of 93 CHB patients （the mild, moderate and severe CHB patients had 21, 37 and 35 cases, respectively） and 28 healthy controls were determined by flow cytometry and enzyme-linked immunosorbent assay （ELISA）. The mRNA expression levels of IL-17 and RAR-related orphan nuclear receptor C （RORC） of purified CD4^＋ T cells after stimulating with anti-CD3 and anti-CD28 antibodies were analyzed by real-time fluorescence polymerase chain reaction（PCR）. The IL-17 levels in the supernatant of purified CD4^＋ T cells after stimulating with anti-CD3 and anti-CD28 antibodies were evaluated by ELISA. The data were analyzed statistically, and their relations with serum HBV DNA load, liver injury markers, and so on were analyzed. Results Compared with those of healthy control group, the proportion of Thl7 cells in peripheral blood of CHB group was significantly higher, and increased with disease severity. The Thl7 cell proportion, IL-17 levels and RORC mRNA levels in severe CHB group were significantly higher than those in moderate and mild CHB groups and healthy control group （P 〈 0.05 ）. There was no statistical significance in serum IL-17 levels among the groups （P 〉 0.05）. The IL-17 levels in the superuatant of purified CD4 ＋ T cells after stimulating with anti-CD3 and anti-CD28 antibodies from CHB group were significantly higher than those from healthy control group（P 〈 0.05 ）, and the IL-17 levels in the supernatant from severe CHB group were higher than those from moderate and mild groups（ P 〈 0.05 ）. The Thl7 cell proportion in peripheral blood of CHB group showed a positive correlation with serum alanine aminotransferase （ALT） level （P 〈 0.01 ）, and showed no correlation with serum HBV DNA load. Conclusions The increased Thl7 cell proportion in CHB patients may be the one of the factors for liver inflammatory response and liver injury and cause the progression of CHB.