Thomas H I
Department of Virology, Preston Public Health Laboratory, Royal Preston Hospital, United Kingdom.
J Med Virol. 1997 Mar;51(3):189-97. doi: 10.1002/(sici)1096-9071(199703)51:3<189::aid-jmv8>3.0.co;2-2.
While resolution of hepatitis B virus (HBV) infection occurs in most cases, a carrier state can exist in which the HBV surface antigen (HBsAg) persists. Some carriers are also positive for the HBV "e" antigen (HBeAg), indicative of high viral replication. Others are HBV "e" antibody (anti-HBe)-positive carriers in whom there appears to be a fall in the level of viral replication with the appearance of antibodies against the "e" antigen. The former group of carrier is considered to be at a higher risk of transmitting HBV infection than the latter. In order that a carrier state may occur, some degree of tolerance to the infectious agent must exist. A study of the rate of increase of specific antibody avidity following infection provides a means of assessing the maturity of the immune response to an infectious agent. Since antibodies specific for the HBV core antigen (HBcAg) are produced in almost all cases of HBV infection and the HBeAg and HBcAg share a large number of amino acids and some B- and T-cell epitopes, the increase in the avidity of antibodies against the HBV core antigen (anti-HBc) in cases of acute, resolving HBV infection and in HBV carriers has, therefore, been studied. An increase in the avidity of specific antibody, similar to that seen in other viral infections, was observed following acute, resolving infection. However, low avidity antibody persisted longer in carriers who remained positive for HBeAg, whereas in cases where there were antibodies specific for HBeAg, the anti-HBc antibody was of high avidity. Analysis of sequential sera from carriers who seroconverted from HBeAg-positive to anti-HBe-positive showed that an increase in anti-core avidity could predate seroconversion from HBeAg-positive to anti-HBe-positive status. Thus, anti-HBc avidity studies may be of diagnostic and prognostic significance.
虽然大多数情况下乙型肝炎病毒（HBV）感染会得到解决，但也可能存在携带者状态，即HBV表面抗原（HBsAg）持续存在。一些携带者的HBV “e”抗原（HBeAg）也呈阳性，这表明病毒复制活跃。其他则是HBV “e”抗体（抗-HBe）阳性携带者，这类携带者中随着抗“e”抗原抗体的出现，病毒复制水平似乎有所下降。前一组携带者被认为比后一组携带者传播HBV感染的风险更高。为了出现携带者状态，机体必须对感染因子存在一定程度的耐受性。研究感染后特异性抗体亲和力的增加速率提供了一种评估对感染因子免疫反应成熟度的方法。由于几乎所有HBV感染病例都会产生针对HBV核心抗原（HBcAg）的特异性抗体，且HBeAg和HBcAg共享大量氨基酸以及一些B细胞和T细胞表位，因此，已经对急性、正在恢复的HBV感染病例和HBV携带者中抗HBV核心抗原（抗-HBc）抗体亲和力的增加情况进行了研究。在急性、正在恢复的感染后观察到特异性抗体亲和力增加，这与在其他病毒感染中观察到的情况类似。然而，HBeAg仍呈阳性的携带者中低亲和力抗体持续时间更长，而在存在抗HBeAg特异性抗体的病例中，抗-HBc抗体具有高亲和力。对从HBeAg阳性血清转化为抗-HBe阳性的携带者的连续血清分析表明，抗核心抗体亲和力的增加可能早于从HBeAg阳性血清转化为抗-HBe阳性状态。因此，抗-HBc亲和力研究可能具有诊断和预后意义。
