Yogisharadhya Revanaiah, Kumar Amit, Ramappa Raghavendra, Venkatesan Gnanavel, Bhanuprakash Veerakyathappa, Shivachandra Sathish Bhadravati
ICAR-National Institute of Veterinary Epidemiology and Disease Informatics (NIVEDI), Bengaluru, 560 064, Karnataka, India.
Pox Virus Laboratory, Division of Virology, ICAR-Indian Veterinary Research Institute (IVRI), Nainital (District), Mukteswar, 263 138, Uttarakhand, India.
Arch Virol. 2017 Apr;162(4):953-962. doi: 10.1007/s00705-016-3178-z. Epub 2016 Dec 19.
Orf, or contagious ecthyma, a highly contagious transboundary disease of sheep and goats, is caused by a double-stranded DNA virus (ORFV) belonging to the genus Parapoxvirus of the family Poxviridae. The ORFV genome encodes the major envelope proteins B2L and F1L, which have been found to be highly immunogenic and have multiple functional characteristics. In order to investigate the functional properties of the B2L protein, in this study, the B2L gene of ORFV strain 59/05, encoding recombinant mature B2L (aa M-D), was produced as a fusion protein in Escherichia coli. The functional characteristics of purified rB2L fusion protein (~60 kDa) were evaluated in vivo and in vitro, showing that this protein had lipase and immunomodulatory activities. Immunization trials involving laboratory animals (mice, rabbits and guinea pigs) using either constant or graded doses of rB2L fusion protein with or without adjuvants (FCA, alum) as well as co-administration with candidate rErns-Ag protein of classical swine fever virus (CSFV) indicated that the rB2L protein is immunogenic and has immunomodulatory properties. This study shows the potential utility of the rB2L protein as a safe and novel adjuvant in veterinary vaccine formulations.
羊口疮，即传染性脓疱性皮炎，是绵羊和山羊的一种高度传染性跨界疾病，由痘病毒科副痘病毒属的双链DNA病毒（羊口疮病毒，ORFV）引起。ORFV基因组编码主要包膜蛋白B2L和F1L，已发现它们具有高度免疫原性且具有多种功能特性。为了研究B2L蛋白的功能特性，在本研究中，ORFV 59/05株的B2L基因编码重组成熟B2L（氨基酸M-D），在大肠杆菌中作为融合蛋白产生。对纯化的rB2L融合蛋白（约60 kDa）的功能特性进行了体内和体外评估，结果表明该蛋白具有脂肪酶和免疫调节活性。使用恒定或分级剂量的rB2L融合蛋白，添加或不添加佐剂（弗氏完全佐剂、明矾）以及与经典猪瘟病毒（CSFV）的候选rErns-Ag蛋白共同给药，对实验动物（小鼠、兔子和豚鼠）进行免疫试验，结果表明rB2L蛋白具有免疫原性和免疫调节特性。本研究表明rB2L蛋白作为兽用疫苗制剂中一种安全、新型佐剂的潜在用途。
