Th17细胞在慢性乙型肝炎及其重症化中的变化

The changes of Th17 cells in the pathogenesis and aggravation of chronic hepatitis B

目的探讨Th17细胞在慢性乙型肝炎（CHB）及其重症化中的变化。方法收集CHB患者32例（CHB组）、HBV相关慢加急性肝功能衰竭（ACLF）患者44例（ACLF组）及健康对照者zO名（健康对照组）。应用流式细胞术检测外周血Th17细胞频率，实时荧光定量PCR检测外周血单个核细胞（PBMC）中IL-17mRNA表达，免疫组织化学检测肝组织内IL-17细胞表达，ELISA检测血清IL-17水平，并动态观察不同预后ACLF患者血清IL-17水平变化趋势。正态分布数据采用方差分析，非正态数据采用Kruskal-WallisH检验或U检验。结果CHB、ACLF和健康对照组外周血PBMC中Th17细胞频率分别为（1．47±0．60）％、（3．20±1．08）％和（0．86±0．43）％；IL-17mRNA分别为4．32±1．77、18．32±8．21和1．00；肝组织内IL-17细胞分别为（10．6±4．8）、（21．1±6．6）和（0．5±0．2）／高倍视野；血清IL-17分别为（15．884-6．51）、（35．03±11．54）和（10．04±4．06）ng／L（均P〈0．05）。中晚期ACLF患者外周血Th17细胞频率和血清IL-17水平均高于早期ACLF患者（均P〈0．01）。ACLF患者外周血Th17细胞频率与国际标准化比值（r=0．44，P〈0．01）和终末期肝病模型评分（r=0．44，P〈0．01）均呈正相关，而CHB患者外周血Th17细胞频率与ALT水平呈正相关（r=0．51，P〈0．01）。另外，ACLF存活患者血清IL-17基线水平低于死亡患者，且经内科治疗后逐渐下降，而死亡患者逐渐升高。结论Th17细胞与其分泌的细胞因子IL一17可能促进了CHB肝脏损伤及其HBV相关ACLF的发生和发展，并且其水平越高可能预示患者短期预后越差。

Objective To explore the changes of Thl7 cells in the pathogenesis and aggravation of chronic hepatitis B （CHB）. Methods Thirty-two CHB patients, 44 hepatitis B virus （HBV）- related acute-on-chronic liver failure （ACLF） patients and 20 healthy controls （HC） were involved in our research. The frequencies of circulating Thl7 cells were detected by flow cytometry. The interleukin 17 （IL-17） mRNA expressions in the peripheral blood mononuclear cells （PBMC） were detected by quantitative real-time polymerase chain reaction （PCR）. Immunohistochemical staining was performed to determine the expressions of IL-17＋ cells in the liver tissues. The serum IL-17 concentrations were detected by enzyme-linked immunosorbent assay （ELISA）, and the dynamic changes in ACLF patients with different prognosis were also observed. Normal distribution data were used by analysis of variance and non-normal distribution data were used by Kruskal-Wallis H test or Mann-Whitney U test. Results In CHB, ACLF and healthy control groups, Thl7 cells frequencies inPBMCwere （1.47±0.60）%, （3. 20＋1.08）% and （0 were 4.32±1. 77, 18.32±8.21 and 1.00, respectively; 4.8）, （21.1±6.6） and （0.5 ±0.2）/high power field; 6.51）, （35.03±11. 54） and （10. 04±4. 06） ng/L, r =86±0.43）%, respectively; IL-17 mRNA IL-17＋ cells in the liver tissues were （10.6=1= the level of IL-17 in serum were （15.88% espectively （all P〈0. 05）. Moreover, the frequencies of circulating Thl7 cells and the levels of serum IL-17 in medium-stage and end-stage ACLF patients were higher than that in early-stage ACLF patients （both P（ 0. 01）. In ACLF patients, the circulating Th17 cells frequencies were positively correlated with international normalized ratio （INR, r=0.44, P〈0.01） and model of end-stage liver disease （MELD） score （r=0.44, P（ 0.01）. And the frequencies o{ circulating Th17 cells were positively associated with the serum alanine ransaminase （ALT） levels in CHB patients （r=0.51, P（0. 01）. Moreover, the survival ACLF patients had an initially lower serum IL-17 level compared with the non-survivors, and the serum IL-17 level showed a gradually decreasing trend during the course of medical treatment In contrast the non- survival group exhibited a gradually increasing trend Conclusions Th17 cell and its eytokine IL-17 may contribute to liver injury in the pathogenesis of CHB and promote the occurrence and the development of HBV-related ACLF. Moreover, the elevated levels of Th17 cells and IL-17 may indicate poor short-term prognosis in ACLF patients~