摘要：
Objective To explore the correlation between serum hepatitis B virus (HBV) X antigen/antibody (HBxAg-wild/HBxAb-wild,and HBxAg-mutant/HBxAb-mutant) and the disease progression in patients with chronic HBV infection.Methods A direct enzyme immunosorbent asssay (ELISA) was performed to detect HBxAb using recombinant antigen,and a double antibody sandwich ELISA assay to detect HBxAg using monoclonal antibody and specific rabbit polyclonal antibody.HBxAg-wild/HBxAb-wild and HBxAg-mutant/HBxAb-mutant were tested in sera from cases at different stages of chronic HBV infection.A chi-square test was employed to examine statistical significance.Results The positive rates of HBxAg-wild and HBxAg-mutant in the chronic asymptomatic HBV carriers,chronic hepatitis,hepatitis B-related cirrhosis and liver cancer were 6.2％ (2/32),10.7％ (3/28),28.6％ (6/21),43.6％ (17/39) and 3.1％ (1/32),10.7％ (3/28),33.3％ (7/21),48.7％ (19/39),respectively.The positive rates of HBxAb-wild and HBxAb-mutant in the above mentioned groups were 6.2％ (2/32),21.4％ (6/28),38.1％ (8/21),53.8％ (21/39)and 6.2％ (2/32),25.0％ (7/28),42.9％ (9/21),61.5％ (24/39) respectively.The positive rates of HBxAg-wild and HBxAg-mutant were not significantly different among the above groups (χ2 =0.871,0.780,0.565 and 0.317,respectively; all P＞0.05) ; The positive rates of HBxAb-wild and HBxAb-mutant were also similar among all the groups (χ2 =0.780,0.709,0.580 and 0.210,respectively; all P＞0.05).The positive rates of HBxAg-wild,HBxAb-wild,HBxAg-mutant,HBxAb-mutant in patients with low viral loads (HBV DNA＜1 × 104 copy/mL) were 36.5％ (23/63),44.4％ (28/63),42.9％ (27/63) and 54.0％ (34/63),respectively,those in patients with high viral loads (HBVDNA≥1×104 copy/mL) were 8.8％ (5/57),15.8％ (9/57),5.3％ (3/57) and 14.0％ (8/57),respectively.The positive rates of HBxAg and HBxAb were significantly higher in cases with low viral loads than those with high viral loads (χ2 =12.869,11.522,22.556 and 20.976,respectively; all P＜0.05).The positive rates of HBxAg-wild,HBxAb-wild,HBxAg-mutant,HBxAb-mutant in the HBeAg positive group were 21.7％ (18/83),30.1％ (25/83),22.9％ (19/83) and 32.5％ (27/83),respectively,while those in the HBeAg negative group were 27.0％ (10/37),32.4％ (12/37),29.7％ (11/37) and 40.5％ (15/37),respectively.No significant difference of HBxAg/HBxAb positive rates between HBeAg positive group and HBeAg negative group was noticed (χ2 =0.408,0.064,0.638 and 0.722,respectively; all P＞0.05).Conclusions The antigenicity and specificity of HBV X protein remains similar after the occurrence of A1762T/G1764A double mutant in X gene.It is also found that the positive rates of HBxAg and HBxAb increase with disease progression.HBxAg/HBxAb might be promoting factors for tumorigenesis in chronic HBV infection.HBxAg and HBxAb might have negative influence on HBV replication.%目的 探讨HBV慢性感染者血清中野生型及A1762T/G1764A双突变型HBV X抗原/抗体(HBxAg-w、HBxAb-w和HBxAg-m、HBxAb m)与HBV慢性感染者疾病进展的相关性.方法 应用重组抗原创建检测HBxAb的直接ELISA法,应用单克隆抗体和特异性兔多克隆抗体创建检测HBxAg的双抗体夹心ELISA法；对不同临床分期HBV慢性感染者血清中的X抗原/抗体进行检测和比较.数据比较采用∥检验.结果 HBxAg-w和HBxAg-m在慢性无症状HBV携带者、慢性乙型肝炎、乙型肝炎相关性肝硬化和肝细胞癌组血清中的阳性率分别为6.2％(2/32)、10.7％(3/28)、28.6％(6/21)、43.6％(17/39)和3.1％(1/32)、10.7％(3/28)、33.3％(7/21)、48.7％(19/39),HBxAb w和HBxAb-m在慢性无症状HBV携带者、慢性乙型肝炎、乙型肝炎相关性肝硬化和肝细胞癌组血清中的阳性率分别为6.2％(2/32)、21.4％(6/28)、38.1％(8/21)、53.8％(21/39)和6.2％(2/32)、25.0％(7/28)、42.9％(9/21)、61.5％(24/39),每组患者HBxAg w与HBxAg m阳性率的差异(x2值分别为0.871、0.780、0.565、0.317)以及HBxAb-w与HBxAb-m阳性率的差异(x2值分别为0.780、0.709、0.580、0.210)均无统计学意义(均P＞0.05).低病毒载量组(HBVDNA＜1×101拷贝/mL)HBxAgw、HBxAbw、HBxAg-m、HBxAb-m阳性率分别为36.5％(23/63)、44.4％(28/63)、12.9％ (27/63)、54.0％ (34/63),高病毒载量组(HBV DNA≥1×104拷贝/mL)HBxAg w、HBxAb w、HBxAg-m、HBxAb-m阳性率分别为8.8％(5/57)、15.8％ (9/57)、5.3％(3/57)、14.0％(8/57),低病毒载量组HBxAg w、HBxAb-w、HBxAg-m、HBxAb-m阳性率显著高于高病毒载量组(x2值分别为12.869、11.522、22.556、20.976,均P＜0.05)；HBeAg阳性组HBxAgw、HBxAb-w、HBxAg m、HBxAb-m阳性率分别为21.7％(18/83)、30.1％(25/83)、22.9％(19/83)、32.5％(27/83),HBeAg阴性组HBxAg w、HBxAb-w、HBxAg-m、HBxAb-m阳性率分别为27.0％(10/37)、32.4％(12/37)、29.7％(11/37)、40.5％ (15/37),HBeAg阳性组与阴性组HBxAg w、HBxAb-w、HBxAg-m、HBxAb-m阳性率的差异均无统计学意义(x2值分别为0.408、0.064、0.638、0.722,均P＞0.05).结论 HBV X基因A1762T/G1764A双突变对HBxAg的抗原性和特异性无明显影响；血清HBxAg和HBxAb随疾病的进展而升高,可能与疾病的发展和乙型肝炎相关性肝细胞癌的形成有关；HBxAg/HBxAb可能具有抑制HBV复制的功能.
