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bioRxiv · 10.1101/2023.05.12.540548

The chicken chorioallantoic membrane model for isolation of CRISPR/cas9-based HSV-1 mutant expressing tumor suppressor p53

Kelishadi, M.·Shahsavarani, H.·Tabarraei, A.·Shokrgozar, M. A.·Teimoori-Toolabi, L.·Azadmanesh, K.
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Abstract

Oncolytic viruses (OVs) have emerged as a novel cancer treatment modality, which selectively target and kill cancer cells while sparing normal ones. Among them, engineered Herpes Simplex Virus type 1 has been proposed to be employed as a potential treatment of cancer and was moved to phase III clinical trials. In this study, to improve oncoselectivity and oncotoxicity properties, the UL39 gene of the ICP34.5 deleted HSV-1 was manipulated with the insertion of the EGFP-p53 expression cassette utilizing CRISPR/ Cas9-mediated editing genome. The {Delta}UL39/{Delta}{gamma}34.5/HSV1-p53 mutant was isolated using the chorioallantoic membrane (CAM) of fertilized chicken eggs as a complementing membrane to support the growth of the viruses with gene deficiencies. Phenotypic characterization of {Delta}UL39/{Delta}{gamma}34.5/HSV1-p53-infected cells was compared with the parent {Delta}{gamma}34.5/HSV-1 in vitro. Our results indicate that the CAM model can be a promising strategy for isolating recombinant virus such as HSV-1-P53 that is unable to replicate in cell lines due to the death induced by exogenous p53 during virus replication.

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Kelishadi, M., Shahsavarani, H., Tabarraei, A., Shokrgozar, M. A., Teimoori-Toolabi, L., Azadmanesh, K.. 2023-05-12. The chicken chorioallantoic membrane model for isolation of CRISPR/cas9-based HSV-1 mutant expressing tumor suppressor p53. https://doi.org/10.1101/2023.05.12.540548

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