Treatment with Exogenous Trypsin Expands In Vitro Cellular Tropism of the Avian Coronavirus Infectious Bronchitis Virus.
Treatment with Exogenous Trypsin Expands In Vitro Cellular Tropism of the Avian Coronavirus Infectious Bronchitis Virus.
复制标题
DOI：
10.3390/v12101102
复制
发表时间：
2020-09-29
期刊：
影响因子：
--
通讯作者：
Bickerton E
中科院分区：
文献类型：
--
作者：
Stevenson-Leggett P;Keep S;Bickerton E
伽玛冠状病毒传染性支气管炎病毒（IBV）在家禽中引起高度传染性和经济上重要的呼吸道疾病。在实验室中，大多数IBV菌株仅限于在离体器官培养物或卵中复制，而不能在细胞培养物中复制，这使得对其基本病毒学的研究变得困难。IBV进入细胞是由病毒粒子表面的大糖蛋白（刺突蛋白）促进的，刺突蛋白由S1和S2亚基组成。先前的研究表明，S2 '裂解位点是IBV Beaudette菌株扩展向性的原因。本研究旨在探讨蛋白酶处理是否可以延长其他IBV菌株的嗜性。在这里，我们证明了在IBV细胞培养繁殖过程中添加外源性胰蛋白酶可显著提高病毒滴度。利用一组表现出不同倾向的IBV菌株，通过在胰蛋白酶存在下的连续传代细胞培养来评估刺突切割对进入和复制的影响。复制可以在连续传代中保持，这表明外源蛋白酶的添加足以克服感染障碍。在细胞培养中连续传代后，在S1和S2亚基中都发现了突变。这项工作证明了外源性蛋白酶可以消除IBV在非允许细胞中复制的障碍，为进一步研究难以捉摸的野株和实现体外可持续的疫苗生产提供了平台。
The Gammacoronavirus infectious bronchitis virus (IBV) causes a highly contagious and economically important respiratory disease in poultry. In the laboratory, most IBV strains are restricted to replication in ex vivo organ cultures or in ovo and do not replicate in cell culture, making the study of their basic virology difficult. Entry of IBV into cells is facilitated by the large glycoprotein on the surface of the virion, the spike (S) protein, comprised of S1 and S2 subunits. Previous research showed that the S2′ cleavage site is responsible for the extended tropism of the IBV Beaudette strain. This study aims to investigate whether protease treatment can extend the tropism of other IBV strains. Here we demonstrate that the addition of exogenous trypsin during IBV propagation in cell culture results in significantly increased viral titres. Using a panel of IBV strains, exhibiting varied tropisms, the effects of spike cleavage on entry and replication were assessed by serial passage cell culture in the presence of trypsin. Replication could be maintained over serial passages, indicating that the addition of exogenous protease is sufficient to overcome the barrier to infection. Mutations were identified in both S1 and S2 subunits following serial passage in cell culture. This work provides a proof of concept that exogenous proteases can remove the barrier to IBV replication in otherwise non-permissive cells, providing a platform for further study of elusive field strains and enabling sustainable vaccine production in vitro.
登录
查看更多内容
影响因子：
4.1
作者：
Bande F;Arshad SS;Bejo MH;Moeini H;Omar AR
通讯作者：
Omar AR
影响因子：
3.7
作者：
Armesto M;Cavanagh D;Britton P
通讯作者：
Britton P
影响因子：
5.4
作者：
Bickerton E;Maier HJ;Stevenson-Leggett P;Armesto M;Britton P
通讯作者：
Britton P
影响因子：
5
作者：
Cavanagh D;Davis PJ;Pappin DJ;Binns MM;Boursnell ME;Brown TD
通讯作者：
Brown TD
影响因子：
5.4
作者：
Hodgson, T;Casais, R;Cavanagh, D
通讯作者：
Cavanagh, D