Small interfering RNA targeting for infected-cell polypeptide 4 inhibits herpes simplex virus type 1 replication in retinal pigment epithelial cells

Background: This study sought to inhibit herpes simplex virus type 1 replication using small interfering RNA which targeting infected-cell polypeptide 4 genes to mediate transcription of early and late viral genes in herpes simplex virus type 1 lytic (productive) infection in retina epithelial cells.

Methods: After pre- or post-infecting with herpes simplex virus type 1, small interfering RNAs were transfected into retina epithelial cells. The antiviral effects of small interfering RNA were evaluated by Western blot, plaque assays, indirect immunofluorescence and reverse transcription polymerase chain reaction. The viral titre was detected by the 50% tissue culture infective dose method.

Results: Small interfering RNA decreased infected-cell polypeptide 4 expression in retina epithelial cells that were infected with herpes simplex virus type 1 before or after small interfering RNA transfection. Compared with herpes simplex virus type 1 infection alone or transfection with negative control small interfering RNA, the viral titre and the retina epithelial cell cytopathic effect were significantly decreased in retina epithelial cells transfected with infected-cell polypeptide 4-targeting small interfering RNA (50 and 100nM) (P<0.05). The small interfering RNA effectively silenced herpes simplex virus type 1 infected-cell polypeptide 4 expression on both mRNA and the protein levels (P<0.05). The inhibition of infected-cell polypeptide 4-targeting small interfering RNA on infected-cell polypeptide 4 protein expression was also verified by Western blot in herpes simplex virus type 1 infected human cornea epithelial cell, human trabecular meshwork cells and Vero cells.

Conclusions: Infected-cell polypeptide 4-targeting small interfering RNA can inhibit herpes simplex virus type 1 replication in retina epithelial cells, providing a foundation for development of RNA interference as an antiviral therapy.