Partial deletion of the HSV gene results in superior packaging capacity of >30 kb foreign DNA with low toxicity as an expression vector. Multiple modified purified oncolytic herpes simplex virus (oHSV) products can avoid evading the host immune response and reduce toxicity by gene knock-out, such as ICP0, ICP4, ICP22, ICP27 or ICP47.https://www.creative-biolabs.com/oncolytic-virus/category-pre-made-oncolytic-herpes-simplex-virus-290.htm