Replication-defective HSV-1 effectively targets trigeminal ganglion and inhibits viral pathopoiesis by mediating interferon gamma expression in SH-SY5Y cells.

It has been widely believed that recurrence of herpes simplex keratitis (HSK) is due to the reactivation of herpes simplex virus type 1 (HSV-1) from latent sites in trigeminal ganglion (TG). However, there are also not effective vectors which could target TG for therapy. Replication-defective HSV-1 vector (rdHSV-IFNγ) was established by calcium phosphate co-transfection of complementing cells. We firstly infected rdHSV-IFNγ to SH-SY5Y, and detected IFNγ expression by western blot, evaluated 50 % cellular cytotoxicity (CC(50)) by ELISA. Antiviral activity of rdHSV-IFNγ was examined by immunofluorescence and antiviral concentration of 50 % effectiveness (EC(50)) assay. The rdHSV-IFNγ vector was immunized to Wistar rats to observe targeting function to TG. Kaplan-Meier survival analysis was utilized to assess security of rdHSV-IFNγ. RT-PCR and immunohistochemistry assay were employed to detect rdHSV-IFNγ localization in TG. Western blot was employed to detect IFNγ expression. rdHSV-IFNγ was successfully established, and performed an effective antiviral activity and higher security in SH-SY5Y. There were no significant differences of survival and corneal infection rate of rdHSV-IFNγ immunized rats among groups (P > 0.05). RT-PCR and immunohistochemistry indicated that expression of glycoprotein D (gD) in TG could target TG and decreased following with times post immunization. Furthermore, IFNγ was expressed effectively in TG tissues. Our findings indicated that established rdHSV-IFNγ vector effectively transported therapeutic gene into TG tissues. The administration of replication-defective vector carrying therapeutic genes may become a promising tool in inhibition or reoccurrence of HSK in clinical.