慢性乙型肝炎患者抗前S1蛋白C末端IgG与干扰素早期应答的相关性

目的 检测B基因型HBV感染慢性乙型肝炎患者血清中抗前S1蛋白C末端(94～117 aa)IgG抗体(简称抗S1),探讨其与干扰素治疗早期应答的关系.方法 采用型特异性引物PCR方法进行基因型测定.对69例使用干扰素治疗的B基因型慢性乙型肝炎患者进行前瞻性研究,其中使用普通干扰素(α-1b、α-2b)42例,聚乙二醇干扰素α-2a 27例,按照HBV B基因型序列合成前S1蛋白C末端(94～117 aa)多肽,用酶联免疫吸附法检测其相应抗体的存在情况.干扰素早期应答以随访12周时的病毒载量下降幅度、转氨酶和HBV血清学标志物的变化为指标进行评价.根据抗S1的反应性将69例B基因型HBV感染的慢性乙型肝炎患者分为抗S1阳性组和抗S1阴性组,评判两组干扰素疗效的差别.数据分析采用SPSS13.0统计软件,两组间计量数据应用t检验或Mann-Whitney U检验,计数数据采用χ~2检验、Fisher's确切概率法或Mann-Whitney U检验,P<0.05为差异有统计学意义.结果 抗S1阳性组21例,阴性组48例,抗S1阳性和阴性组间干扰素种类差异无统计学意义.治疗12周时,抗S1阳性组和阴性组HBV DNA下降水平平均分别为3.37log_(10)拷贝/ml和0.33log_(10)拷贝/ml,Z=-3.658,P=0.000;ALT下降水平平均分别为92 U/L和30.5U/L,Z=-2.132,P=0.033,差异均有统计学意义.治疗12周时,抗Sl阳性组和阴性组HBeAg阴转率分别为41.2%(7/17)和5.9%(1/17);血清学转换率分别为12.8%(5/39)和0(0/39),Z=-5.11,P=0.000;病毒学应答率分别为71.4%(15/21)和16.7%(8/48),χ~2=19.710,P=0.000;完全应答率分别为23.8%(5/21)和6.2%(3/48),部分应答率分别为52.4%(11/21)和18.8%(9/48),Z=-4.840,P=0.000,差异均有统计学意义.抗S1在预测干扰素的早期应答中阳性预测值为71.4%,阴性预测值则为83.3%.结论 通过对治疗前血清中抗S1的检测,可以筛选出合适的慢性乙型肝炎患者,进行个体化治疗,提高干扰素治疗的应答率.

Association between IgG antibody against the C-terminal region of the preS1 protein of hepatitis B virus and the early response to interferon therapy in chronic hepatitis B

Objective To determine the relationship between IgG antibody against the C-terminal region of the preS1 protein of hepatitis B virus and the early response to interferon therapy in chronic hepatitis B. Methods 69 patients with chronic hepatitis B virus (genotype B) infection were recruited in this study. 42 patients were treated with interferon- α -1b or α-2b, and 27 patients were treated with PEG interferon (α -2a). Peptide mimicking the C-terminal region of the preS1 protein (94-117aa) of genotype B HBV were synthesised, and the IgG antibody against this peptide was measured by ELISA, and the early response to IFN-alpha therapy was judged by the effect on the viral kinetics, transaminase and the status of HBeAg at 12th week after the treatment. Results 21 patients were positive for anti-preS1 antibody, and 48 patients were negative for anti-preS1 antibody. After 12 weeks of the treatment, the average decrease in viral levels was 3.37 log_(10) copies/ml and 0.33 log_(10) copies/ml in anti-PreS1 positive patients and anti-preS1 negative patients, respectively, the difference between the two groups was significant (Z = -3.658, P = 0.000); the average decrease in ALT levels was 92 U/L and 30.5 U/L in these two groups, respectively (Z= -2.132, P = 0.033). The rate of hepatitis B e antigen (HBeAg) loss was 41.2% (7/17) and the rate of anti-Hbe seroconversion was 5.9% (1/17) in anti-PreS 1 positive group, however, the rate of hepatitis B e antigen loss was only 12.8% (5/39), and none of the patients in anti-PreS1 negative group showed anti-Hbe seroconversion, the difference between the two groups was significant (Z = -5.110, P = 0.000). The rates of response were 71.4% (15121) and 16.7% (8/48), respectively, in anti-PreS1 positive group and anti-PreSl negative group. The rates of complete response were 23.8% (5/21) and 6.25% (3/48), respectively, in these two groups. The positive predictive value (PPV) of anti-C-terminal region of preS1 (94-117aa) antibody in predicting early response was 71.6% and the negative predictive value (NPV) was 83.3%. Conclusions Detection of anti-C-terminal region of preS1 (94-117aa) antibody may help to improve the efficacy of INF-alpha therapy for chronic hepatitis B (CHB).