On the evolution of Avian infectious bronchitis virus in VERO cells
Keywords:IBV, Spike, Evolution, In vitro
Avian infectious bronchitis virus (IBV) (Nidovirales: Coronaviridae) is a chicken Gammacoronavirus with the highestevolution rate in the genus and, despite the recently reported proofreading activity of its polymerase, intra and interhost diversity is a well-documented phenomenon. This study aimed to assess the genetic variation of serial passages of a variant genotype IBV strain in vitro. Strain CRG-BETA, propagated in chicken embryos, was inoculated in VERO cells monolayers up to the 4th passage and each passage was monitored with an RT-PCR targeted to the S1 gene (nt 705to 1094) and an RT-PCR to the protein 5a mRNA. All passages were positive to RT-PCRs to S1 and passages 1 to 3 to5a mRNA; S1 sequences showed no polymorphism. The finding of IBV mRNA in the cell cultures demonstrates that the CRG-BETA IBV strain is replicating in the VERO cells and regarding S1 sequence analysis, the lack of nucleotide mutations shows that CRG-BETA might have reached a fixed status. As a conclusion, different genotypes of IBV present different evolutionary patterns not only in vivo as previously known, but also in vitro, as described herein.
How to Cite
The journal content is authorized under the Creative Commons BY-NC-SA license (summary of the license: https://