IFNA1 and neuroblastoma: Consistently, we observed a similar reduction of the plaque initiation of the KOS-C65A mutant on human keratinocyte (HaCaT), retinal pigment epithelial (RPE-1), and neuroblastoma (SK-N-SH) cell lines (Fig. 2B), which were treated with an IFN-α dose that induced comparable inhibitory effects against wild type HSV-1 on the different cell lines.