Characterization and mutagenesis of Chinese hamster ovary cells endogenous retroviruses to inactivate viral particle release.

ABSTRACT: The Chinese hamster ovary (CHO) cells used to produce biopharmaceutical proteins are known to contain type-C endogenous retrovirus (ERV) sequences in their genome and to release retroviral-like particles. Although evidence for their infectivity is missing, this has raised safety concerns. As the genomic origin of these particles remained unclear, we characterized type-C ERV elements at the genome, transcriptome, and viral particle RNA levels. We identified 173 type-C ERV sequences clustering into three functionally conserved groups. Transcripts from one type-C ERV group were full-length, with intact open reading frames, and cognate viral genome RNA was loaded into retroviral-like particles, suggesting that this ERV group may produce functional viruses. CRISPR-Cas9 genome editing was used t

SUBMITTER: Duroy PO 

PROVIDER: S-EPMC7003738 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature