Lega L, Resti M, Rossi M E, Azzari C, Botarelli P, Vierucci A
Clinica Pediatrica III, Ospedale A. Meyer, Firenze, Italia.
Pediatr Med Chir. 1993 Jan-Feb;15(1):5-10.
Hepatitis B virus (HBV) is one of the most important causes of chronic liver disease. HBV is a DNA virus with an external glycoprotein surface and an internal nucleocapsid which contains the viral genome. HBV infection is revealed by the appearance of specific markers. Some of these markers are well known and their presence in serum is important to understand the behaviour of the disease. Among them HBsAg, HBeAg, anti-HBs and anti-HBe are found in serum, so as anti-Core; the HBcAg may be found in hepatic tissue and marks infectivity and virus replication. In the few last years some new antigens and antibodies have been studied and their importance in diagnosis and follow-up of hepatitis has been recognized. HBxAg, Pre-S and DNA-Polymerase (Pol) seem to be specific and early signals of viral replication. More studies showed the trans-activating properties of HBxAg; actually the X protein seems to be involved in replicative cycle of HBV. Many Authors also demonstrated a relationship between the presence of X in serum and/or liver and the progression of disease to cirrhosis and hepatocellular carcinoma. The Pol antigen and its antibody seem to be very common markers of HBV infection in serum of patients with hepatitis. Moreover their presence is the only signal of viral infection in some patients which have no other marker of HBV. More studies are of course needed to exactly establish the significance of these new markers and their importance for diagnosis and prognosis of HBV infection.
乙型肝炎病毒（HBV）是慢性肝病最重要的病因之一。HBV是一种DNA病毒，具有外部糖蛋白表面和内部核衣壳，核衣壳中含有病毒基因组。HBV感染通过特定标志物的出现得以揭示。其中一些标志物广为人知，它们在血清中的存在对于理解疾病的表现很重要。血清中可检测到HBsAg、HBeAg、抗-HBs和抗-HBe，抗-HBc也如此；HBcAg可在肝组织中发现，标志着传染性和病毒复制。在过去几年中，一些新的抗原和抗体得到了研究，它们在肝炎诊断和随访中的重要性已得到认可。HBxAg、前S抗原和DNA聚合酶（Pol）似乎是病毒复制的特异性早期信号。更多研究表明了HBxAg的反式激活特性；实际上，X蛋白似乎参与了HBV的复制周期。许多作者还证明了血清和/或肝脏中X的存在与疾病进展为肝硬化和肝细胞癌之间的关系。Pol抗原及其抗体似乎是肝炎患者血清中HBV感染非常常见的标志物。此外，在一些没有其他HBV标志物的患者中，它们的存在是病毒感染的唯一信号。当然，还需要更多研究来确切确定这些新标志物的意义及其对HBV感染诊断和预后的重要性。
