IRF7-deficient MDBK cell based on CRISPR/Cas9 technology for enhancing IBRV replication.

Area of Science:

• Veterinary Virology
• Cell Biology
• Immunology

Background:

• Infectious bovine rhinotracheitis (IBR), caused by bovine alphaherpesvirus-1 (BoAHV-1), is a significant cattle disease managed by vaccination.
• Madin-Darby bovine kidney (MDBK) cells are crucial for IBR vaccine production but are subject to innate immune gene inhibition of viral replication.

Purpose of the Study:

• To develop IRF7-deleted MDBK cells to enhance bovine alphaherpesvirus-1 (BoAHV-1) replication.
• To facilitate the production of high-titer infectious bovine rhinotracheitis (IBR) vaccines.

Main Methods:

• CRISPR/Cas9 technology was employed to knockout the IRF7 gene in MDBK cells.
• Virus growth curves, CCK-8 assays, cell scratch assays, and qPCR were used to assess viral replication and gene expression.

Main Results:

• IRF7 knockout in MDBK cells significantly increased IBRV replication capacity.
• A notable reduction in type I interferons (IFN-α and IFN-β) expression was observed in IRF7 knockout cells.
• The IRF7-/- MDBK cell lines demonstrated enhanced production of high-titer IBRV.

Conclusions:

• IRF7 knockout MDBK cell lines are effective for high-titer IBRV production.
• This advancement supports the development of more effective inactivated or attenuated IBR vaccines.