慢性乙型肝炎患者外周血细胞因子IL-17A、IL-2、IL-21、IL-4表达水平及意义

目的 探索初治慢性乙型肝炎（CHB）患者外周血中细胞因子表达水平及其与病毒载量和肝脏炎症程度的关系，以期为临床动态评估病情和预后方面提供新思路。方法 选择2018年10月至2019年11月就诊于海军军医大学第一附属医院感染科的初治慢性乙型肝炎病毒（HBV）感染者68例，健康对照者12名，通过ELISA检测外周血中细胞因子IL-17A、IL-2、IL-21和IL-4表达水平，同时检测HBV DNA及转氨酶水平。统计学处理采用Mann-Whitney U检验、Kruskal-Wallis H检验及Spearman相关性分析。结果 相较于健康对照者，初治CHB患者外周血IL-17A高 [17.50（11.99，25.36）vs14.14（9.01,23.68）pg/ml，Z=-2.001，P=0.045]，IL-2低[57.19（31.10，79.92）vs73.06（62.41，105.84）pg/ml，Z=-2.509，P=0.012]，IL-21高[37.12（23.85，77.66）vs（20.95±5.72）pg/ml，Z=-3.485，P<0.01]，IL-4表达水平无差异。不同免疫状态的IL-17A表达有明显差异（H=8.870，P=0.031）。炎症活动状态CHB患者的IL-17A和IL-21更低、IL-2更高（P＜0.05），IL-4无差异（P＞0.05）。HBeAg阳性CHB患者、HBeAg阴性CHB患者与健康对照者外周血细胞因子IL-17A、IL-2、IL-21比较，差异有统计学意义（IL-17A：H=10.061，P=0.007；IL-2：H=6.576，P=0.037；IL-21：H=12.444，P=0.002）。初治CHB患者外周血IL-17A、IL-21、IL-4与HBV DNA无相关性（r=0.02、0.23、0.07，均P>0.05），IL-2与HBV DNA存在弱相关（r=0.32，P=0.01）。初治HBV患者外周血IL-17A、IL-21与ALT存在相关性（IL-17A：r=0.59，P<0.01；IL-21：r=0.49，P<0.01），与AST存在相关性（IL-17A：r=0.47，P<0.01；IL-21：r=0.36，P<0.01），而IL-2、IL-4与ALT和AST均无明显相关。ALT≥300U/L的初治CHB组、ALT＜300U/L的初治CHB组与健康对照者外周血细胞因子IL-17A、IL-2、IL-21比较，差异有统计学意义（IL-17A：H=27.557，P<0.01；IL-2：H=8.581，P=0.014；IL-21：H=21.438，P<0.01）。ROC曲线分析结果显示，IL-17A判断肝脏炎症程度的AUC值为0.8933（95%CI：0.7930-0.9936），IL-21判断肝脏炎症程度的AUC值为0.7600（95%CI：0.6227-0.8973）。结论 IL-17A、IL-2和IL-21参与慢性HBV感染进程：初治CHB患者无论HBeAg阳性与否或炎症程度高低，外周血IL-17A和IL-21升高，IL-2下降；IL-2与HBV DNA有一定相关性；IL-17A和IL-21与ALT及AST均存在正相关；检测IL-17A和IL-2有助于病情评估与预后判断。

Expression and significance of cytokines IL-17A, IL-2, IL-21 and IL-4 from peripheral blood of patients with chronic hepatitis B

Objective: To explore the level of cytokine in peripheral blood of chronic hepatitis B (CHB) patients and its relationship with viral load and degree of liver inflammation, in order to provide new ideas for clinical dynamic assessment of disease and prognosis. Methods: A total of 68 treatment-na?ve CHB patients admitted to the Department of Infection, The First Hospital Affiliated to Naval Medical University from October 2018 to November 2019 and 12 healthy controls were enrolled. The expression levels of cytokines IL-17A, IL-2, IL-21 and IL-4 in peripheral blood were tested by ELISA. HBV DNA and transaminase were detected meanwhile. Mann-Whitney U test, Kruskal-Wallis H test and Spearman correlation analysis were used for statistical analysis. Results: Compared with healthy controls, peripheral blood IL-17A in treatment-na?ve CHB patients was higher [17.50 (11.99, 25.36) vs14.14 (9.01,23.68) pg/ml, Z=-2.001, P=0.045], IL-2 was lower [57.19 (31.10, 79.92) vs73.06 (62.41, 105.84) pg/ml, Z=-2.509, P=0.012], and IL-21 was higher [37.12 (23.85, 77.66) vs (20.95±5.72) pg/ml, Z=-3.485, P<0.01], there was no difference in IL-4 expression. The expression of IL-17A in different immune states was significantly different (H=8.870, P=0.031). In CHB patients with inflammatory activity, IL-17A and IL-21 were lower, IL-2 was higher（P＜0.05）, and IL-4 was not different（P＞0.05）. There were statistically significant differences in peripheral blood cytokines IL-17A, IL-2 and IL-21 between HBeAg-positive CHB patients and HBeAg-negative CHB patients and healthy controls (IL-17A: H=10.061, P=0.007; IL-2: H=6.576, P=0.037; IL-21: H=12.444, P=0.002). There was no correlation between IL-17A, IL-21, IL-4 and HBV DNA in peripheral blood of treatment-na?ve CHB patients (r=0.02, 0.23, 0.07, P>0.05), IL-2 was weakly correlated with HBV DNA (r=0.32, P=0.01). There was a correlation between IL-17A, IL-21 and ALT in peripheral blood of treatment-na?ve HBV patients (IL-17A: r=0.59, P<0.01; IL-21: r=0.49, P<0.01), and with AST (IL-17A: r=0.47, P<0.01; IL-21: r=0.36, P<0.01), while IL-2 and IL-4 had no significant correlation with ALT and AST. The serum cytokines IL-17A, IL-2 and IL-21 in the CHB group with ALT≥300U/L and in the CHB group with ALT < 300U/L were significantly different from those in healthy control group (IL-17A: H=27.557, P<0.01; IL-2: H=8.581, P=0.014; IL-21: H=21.438, P<0.01). ROC curve analysis results showed that the AUC value of IL-17A to judge the degree of liver inflammation was 0.8933 (95%CI: 0.7930-0.9936), and the AUC value of IL-21 to judge the degree of liver inflammation was 0.7600 (95%CI: 0.6227-0.8973). Conclusion: IL-17A, IL-2 and IL-21 are involved in the progression of chronic HBV infection: regardless of whether HBeAg was positive or not or the degree of inflammation, IL-17A and IL-21 in peripheral blood of CHB patients were increased, while IL-2 was decreased. IL-2 has a certain correlation with HBV DNA. IL-17A and IL-21 were positively correlated with ALT and AST. Detection of IL-17A and IL-2 is helpful for disease assessment and prognosis.