Snyder D B, Vakharia V N, Mengel-Whereat S A, Edwards G H, Savage P K, Lütticken D, Goodwin M A
Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park 20742.
Avian Dis. 1994 Oct-Dec;38(4):701-7.
The VP2 structural gene encoded in the large genomic segment A of the variant GLS strain of infectious bursal disease virus (IBDV) was modified to encode a neutralization epitope (B69), found only on classic strains of IBDV. A chimeric cDNA clone of the large segment A, encoding VP3, VP4, and the modified variant IBDV VP2 structural proteins, was expressed in a recombinant baculovirus. The chimeric protein expressed was assessed with a panel of neutralizing monoclonal antibodies (MAbs), and it contained not only all previously MAb-defined GLS variant strain epitopes but also the B69 neutralization epitope found on classic IBDV strains. Complete active protection was afforded to specific-pathogen-free chickens by a subunit chimeric vaccine against virulent challenge with the classic IM and STC strains, as well as against the variant E/Del and GLS IBDV strains. Compared with a previously tested recombinant subunit vaccine, which incorporated unmodified baculovirus-expressed large-segment A GLS proteins, the recombinant chimeric subunit vaccine resulted in markedly improved active cross-protection against classic IBDV challenge.
传染性法氏囊病病毒（IBDV）变异GLS株的大基因组片段A中编码的VP2结构基因被修饰，以编码仅在IBDV经典株上发现的中和表位（B69）。编码VP3、VP4和修饰的变异IBDV VP2结构蛋白的大片段A的嵌合cDNA克隆在重组杆状病毒中表达。用一组中和单克隆抗体（MAb）对表达的嵌合蛋白进行评估，它不仅包含所有先前由MAb定义的GLS变异株表位，还包含在经典IBDV株上发现的B69中和表位。一种亚单位嵌合疫苗为无特定病原体的鸡提供了完全的主动保护，使其免受经典IM和STC株的强毒攻击，以及变异E/Del和GLS IBDV株的攻击。与先前测试的重组亚单位疫苗相比，后者包含未修饰的杆状病毒表达的大片段A GLS蛋白，重组嵌合亚单位疫苗在针对经典IBDV攻击的主动交叉保护方面有显著改善。
