Schlicht H J, Kuhn C, Guhr B, Mattaliano R J, Schaller H
J Virol. 1987 Jul;61(7):2280-5. doi: 10.1128/JVI.61.7.2280-2285.1987.
To examine the envelope proteins of duck hepatitis B virus (DHBV), which are encoded by the pre-S/S open reading frame of the viral genome, an antiserum was raised in rabbits against a fusion protein comprising most of the pre-S coding segment. By using this antiserum, viral particles could be precipitated from serum, and two pre-S proteins with molecular sizes of approximately 35 and 37 kilodaltons were detected in the sera and livers of DHBV-infected ducks after Western blotting and after biosynthetic labeling of a primary duck liver cell culture. In serum, the pre-S proteins were shown to exist predominantly in DHBV-DNA-free particles associated with a 17-kilodalton protein which, by N-terminal amino acid sequence analysis, was shown to represent the viral S protein which is encoded by the 3' proximal segment of the DHBV pre-S/S open reading frame. To compare the immunogenic potential of the S and pre-S proteins, serum particles and gel-purified S protein were used to immunize rabbits. In neither case was a significant immune response against the DHBV S protein observed. However, a good antibody titer against DHBV pre-S was obtained even after immunization with small amounts of the pre-S antigen.
为了研究鸭乙型肝炎病毒（DHBV）的包膜蛋白（由病毒基因组的前S/S开放阅读框编码），制备了一种兔抗血清，该抗血清针对包含大部分前S编码片段的融合蛋白。使用这种抗血清，可以从血清中沉淀出病毒颗粒，并且在对原代鸭肝细胞培养物进行生物合成标记后以及Western印迹分析后，在感染DHBV的鸭的血清和肝脏中检测到两种分子大小约为35和37千道尔顿的前S蛋白。在血清中，前S蛋白主要存在于与一种17千道尔顿蛋白相关的无DHBV-DNA颗粒中，通过N端氨基酸序列分析表明，该蛋白代表由DHBV前S/S开放阅读框3'近端片段编码的病毒S蛋白。为了比较S蛋白和前S蛋白的免疫原性潜力，使用血清颗粒和凝胶纯化的S蛋白免疫兔子。在这两种情况下，均未观察到针对DHBV S蛋白的显著免疫反应。然而，即使在用少量前S抗原免疫后，也获得了针对DHBV前S的良好抗体滴度。
