Objective: To explore the significance of triggering receptor expressed on myeloid cells-2 (TREM-2) prognostic evaluation so as to provide novel biological markers in clinical practice for patients with hepatitis B virus-related acute-on-chronic liver failure ( HBV-ACLF). Methods: The research subjects of this study were divided into an experimental group and a control group. Fifty HBV-ACLF cases admitted to the Department of Infectious Diseases of the First Affiliated Hospital of Nanchang University from January 1, 2019 to December 31, 2019 were selected as the experimental group. Patients were divided into survival and death groups according to the actual prognosis at discharge (self-discharge and dead patients were considered death groups, and all enrolled patients were hospitalized for more than 28 days). Twenty-five healthy subjects were chosen as the control group. Peripheral venous blood was collected from the experimental group and the control group. Plasma and peripheral blood mononuclear cells (PBMC) were isolated. The concentrations of TREM-2, interleukin (IL)-6, and IL-8 were detected in the plasma. TREM-2 mRNA expression was detected in PBMC. A single blood sample was collected from the control group, whereas five blood samples were dynamically collected from the experimental group on the day of admittance and at 7, 14, 21, and 28 days after treatment commenced. Simultaneously, upon admission, the relevant clinical indicators of HBV-ACLF patients were monitored, including the liver function test: alanine aminotransferase, aspartate aminotransferase, total bilirubin, albumin, coagulation function test: international normalized ratio, prothrombin time, and other indicators. Measurement data were expressed as mean±standard deviation (x±s). Count data were compared and analyzed using the χ(2) test. The intra-group factor mean was compared using a repeated measures ANOVA. The means were analyzed by t-tests between the two groups. Bivariate correlation analysis was used to analyze the correlation between the two variables. The value of TREM-2 as a diagnostic marker was analyzed using the receiver operating characteristic (ROC) curve. Results: The mRNA expression of TREM-2 in the PBMC of HBV-ACLF patients showed a gradually increasing trend at various time points and was significantly higher in the survival group than that of the control group at 28 days (P < 0.01), while the death group showed a gradually weakening trend at various time points and was significantly lower than the control group at 28 days (P < 0.01). (1) The levels of TREM-2 in the plasma of HBV-ACLF patients generally showed a gradually increasing trend at various time points in the survival group. The levels on the day of admission and 7, 14, 21, and 28 days after the initiation of treatment were (1.49±0.85), (1.62±0.58), (1.95±0.69), (2.33±0.71), and (2.00±0.67) ng/ml, respectively. The expression of TREM-2 in the death group showed a gradually weakening trend at various time points. The levels on the day of admission and 7, 14, 21, and 28 days after initiation of treatment were (1.40±0.73), (1.59±0.79), (1.56±0.80), (1.05±0.49), and (0.81±0.21) ng/ml, respectively. The survival group's various detection time points were higher than those of the death group, and the difference was statistically significant. The plasma level of TREM-2 in the healthy control group was (1.25±0.35) ng/ml. (2) The concentrations of IL-6 and IL-8 in the plasma of HBV-ACLF patients showed a gradually decreasing trend at various time points in the survival group. The levels on the day of admission and 7, 14, 21, and 28 days after initiation of treatment were (46.70±26.31), (33.98±20.28), (19.07±10.24), (14.76±7.84), (9.12±7.65) and (108.29±47.07), (93.85±26.53), (79.27±34.63), (56.72 ±18.30), (37.81±13.88) pg/ml, respectively. However, its concentration in the death group fluctuated within a relatively high range. The levels on the day of admission and 7, 14, 21, and 28 days after the initiation of treatment were (41.94±24.19), (36.99±19.78), (34.30±20.62), (34.14±14.52), (36.64±23.61) and (104.65±50.16), (112.98±45.03), (118.43±45.00), (111.67±40.44), (109.55±27.54) pg/ml, respectively. (3) Bivariate correlation analysis results indicated that the plasma TREM-2 content was negatively correlated with the plasma levels of pro-inflammatory cytokines IL-6 and IL-8 (r = -0.224, P = 0.025; r = - 0.223, P = 0.026). ROC curve analysis showed that the mRNA levels of TREM-2 in PBMCs at various time points for prognostic evaluation of HBV-ACLF patients were 1d=0.667, 7d=0.757, 14d=0.979, 21d=0.986, and 28d= 0.993. The areas under the ROC curve of the TREM-2 content in the plasma at various time points were 1d=0.522, 7d=0.571, 14d=0.658, 21d=0.927, and 28d=0.994. Conclusion: TREM-2 mRNA expression in PBMC and TREM-2 content in plasma have a significant relationship to the prognosis of HBV-ACLF patients and may inhibit the liver inflammatory response by regulating the secretion of pro-inflammatory cytokines IL-6 and IL-8. Dynamic monitoring of TREM-2 expression in peripheral blood is favorable for evaluating the prognostic condition of HBV-ACLF patients.
目的： 探讨髓样细胞触发受体2（TREM-2）在HBV相关慢加急性肝衰竭（HBV-ACLF）疾病预后判断中的意义，以期为临床上HBV-ACLF患者的预后判断提供新的生物学标志物。 方法： 将研究对象分为实验组及对照组，实验组：选取2019年1月1日至2019年12月31日于南昌大学第一附属医院感染科收治的HBV-ACLF患者50例，依据患者出院时的实际预后情况将其分为生存组及死亡组（自动出院及死亡患者均视为死亡组，所有入组患者住院时间均超过28d）。对照组：健康人25名。采集实验组及对照组外周静脉血，分离出血浆及外周血单个核细胞（PBMC），检测其血浆中的TREM-2、白细胞介素（IL）-6、IL-8的浓度，检测PBMC中TREM-2的mRNA的表达。对照组只采集1次血液样本，而实验组则动态采取5次血液样本，时间分别为入院当天，开始治疗后7、14、21、28 d。同时监测HBV-ACLF患者入院时的相关临床指标，包括肝功能丙氨酸转氨酶、天冬氨酸转氨酶、总胆红素、白蛋白及凝血功能国际标准化比值、凝血酶原时间等指标。计量资料以均数±标准差（x±s）表示。计数资料应用χ(2)检验进行比较分析；组内均数的比较采用重复测量因素的方差分析；用t检验对两组间的均数进行分析；两个变量间的相关性分析采用双变量相关分析；用受试者操作特征（ROC)曲线对TREM-2作为诊断标志物的价值进行分析。 结果： HBV-ACLF患者PBMC中TREM-2的mRNA表达在生存组的各个时间点呈现出逐渐增加的趋势，且28 d时显著高于对照组（P < 0.01）。而在死亡组的各个时间点呈现出逐渐减弱的趋势，于28 d时显著低于对照组（P < 0.01）。（1）HBV-ACLF患者血浆中的TREM - 2的含量在生存组的各个时间点总体上呈现出逐渐增加的趋势，入院当天、开始治疗后7、14、21、28 d的水平分别为（1.49±0.85）、（1.62±0.58）、（1.95±0.69）、（2.33±0.71）、（2.00±0.67） ng/ml。而死亡组TREM-2的表达在各个时间点呈现出逐渐减弱的趋势，入院当天、开始治疗后7、14、21、28 d的水平分别为(1.40±0.73)、(1.59±0.79)、(1.56±0.80)、(1.05±0.49)、(0.81±0.21) ng/ml。生存组在各检测时间点均高于死亡组，差异有统计学意义。健康对照组血浆中的TREM-2的水平为（1.25±0.35）ng/ml。（2）HBV-ACLF患者血浆中的IL-6、IL-8的浓度在生存组的各个时间点呈现出逐渐降低的趋势，入院当天、开始治疗后7、14、21、28d的水平分别为（46.70±26.31）、（33.98±20.28）、（19.07±10.24）、（14.76±7.84）、(9.12±7.65)pg/ml及(108.29±47.07)、(93.85±26.53)、(79.27±34.63)、(56.72±18.30)、(37.81±13.88) pg/ml。而其在死亡组的浓度则在较高范围内波动，入院当天、开始治疗后7、14、21、28d的水平分别为(41.94±24.19)、(36.99±19.78)、(34.30±20.62)、(34.14±14.52)、(36.64±23.61)pg/ml及(104.65±50.16)、(112.98±45.03)、(118.43±45.00)、(111.67±40.44)、(109.55±27.54) pg/ml。（3）双变量相关性分析结果提示血浆中TREM-2的含量与血浆中促炎细胞因子IL-6、IL-8的水平均呈负相关(r = -0.224，P = 0.025；r = -0.223，P = 0.026)。ROC曲线分析，各个时间点的PBMC中TREM-2的mRNA的水平对HBV-ACLF患者预后判断的ROC的曲线下面积分别为1d=0.667，7d=0.757，14d=0.979，21d=0.986，28d=0.993。而其血浆中TREM-2的含量在各个时间点的ROC的曲线下面积分别为1d=0.522，7d=0.571，14d=0.658，21d=0.927，28d=0.994。 结论： PBMC中TREM-2的mRNA表达及血浆中TREM-2的含量与HBV-ACLF患者的预后存在明显的相关性，其可能通过调节促炎细胞因子IL-6、IL-8的分泌抑制肝脏炎症反应，动态监测TREM-2在外周血的表达有利于判断HBV-ACLF患者的预后情况。.
Keywords: HBV-related acute-on-chronic liver failure; IL-6; IL-8; TREM-2.