Choi Eun-hye, Song Min-Suk, Park Su-Jin, Pascua Philippe Noriel Q, Baek Yun Hee, Kwon Hyeok-il, Kim Eun-Ha, Kim Semi, Jang Hyung-Kwan, Poo Haryoung, Kim Chul-Joong, Choi Young Ki
Department of Microbiology, College of Medicine and Medical Research Institute, Chungbuk National University, 12 Gaeshin-Dong Heungduk-Ku, Cheongju, 361-763, Republic of Korea.
Arch Virol. 2015 Jul;160(7):1729-40. doi: 10.1007/s00705-015-2442-y. Epub 2015 May 12.
An increasing number of outbreaks of avian influenza H5N1 and H9N2 viruses in poultry have caused serious economic losses and raised concerns for human health due to the risk of zoonotic transmission. However, licensed H5N1 and H9N2 vaccines for animals and humans have not been developed. Thus, to develop a dual H5N1 and H9N2 live-attenuated influenza vaccine (LAIV), the HA and NA genes from a virulent mouse-adapted avian H5N2 (A/WB/Korea/ma81/06) virus and a recently isolated chicken H9N2 (A/CK/Korea/116/06) virus, respectively, were introduced into the A/Puerto Rico/8/34 backbone expressing truncated NS1 proteins (NS1-73, NS1-86, NS1-101, NS1-122) but still possessing a full-length NS gene. Two H5N2/NS1-LAIV viruses (H5N2/NS1-86 and H5N2/NS1-101) were highly attenuated compared with the full-length and remaining H5N2/NS-LAIV viruses in a mouse model. Furthermore, viruses containing NS1 modifications were found to induce more IFN-β activation than viruses with full-length NS1 proteins and were correspondingly attenuated in mice. Intranasal vaccination with a single dose (10(4.0) PFU/ml) of these viruses completely protected mice from a lethal challenge with the homologous A/WB/Korea/ma81/06 (H5N2), heterologous highly pathogenic A/EM/Korea/W149/06 (H5N1), and heterosubtypic highly virulent mouse-adapted H9N2 viruses. This study clearly demonstrates that the modified H5N2/NS1-LAIV viruses attenuated through the introduction of mutations in the NS1 coding region display characteristics that are desirable for live attenuated vaccines and hold potential as vaccine candidates for mammalian hosts.
家禽中H5N1和H9N2禽流感病毒爆发次数不断增加，造成了严重经济损失，并因存在人畜共患病传播风险而引发了对人类健康的担忧。然而，尚未研发出用于动物和人类的H5N1和H9N2许可疫苗。因此，为研发一种H5N1和H9N2双价减毒活流感疫苗（LAIV），分别将来自一株强毒力的适应小鼠的禽H5N2（A/WB/韩国/ma81/06）病毒和一株近期分离的鸡H9N2（A/CK/韩国/116/06）病毒的HA和NA基因，导入表达截短型NS1蛋白（NS1-73、NS1-86、NS1-101、NS1-122）但仍拥有全长NS基因的A/波多黎各/8/34骨架中。与全长和其余H5N2/NS-LAIV病毒相比，两种H5N2/NS1-LAIV病毒（H5N2/NS1-86和H5N2/NS1-101）在小鼠模型中高度减毒。此外，发现含有NS1修饰的病毒比具有全长NS1蛋白的病毒诱导更多的IFN-β激活，并且在小鼠中相应地减毒。用单剂量（10(4.0) PFU/ml）的这些病毒进行鼻内接种，可完全保护小鼠免受同源A/WB/韩国/ma81/06（H5N2）、异源高致病性A/EM/韩国/W149/06（H5N1）以及异亚型高毒力适应小鼠的H9N2病毒的致死性攻击。这项研究清楚地表明，通过在NS1编码区引入突变而减毒的修饰H5N2/NS1-LAIV病毒表现出减毒活疫苗所需的特性，并有望成为哺乳动物宿主的候选疫苗。
