CD274 and neoplasm: To assess the risk, we injected E0771 tumor-bearing mice intratumorally with 1E06 PFU CF33-hNIS-anti-PD-L1 and then housed them with other mice, with or without tumors, that were not injected with virus, as shown in Figure 6A. The dose of virus used in this study was chosen at 10-fold higher than the highest dose used in the toxicology study, to rule out the possibility of virus transmission from injected to non-injected mice.