Abstract
Objective—To assess the effect of interferon (IFN)-α on viability of feline corneal epithelial cells, replication of feline herpesvirus (FHV)-1, and virus-induced cytopathic changes.
Sample Population—Healthy eyes from 10 recently euthanatized cats.
Procedure—4 replicate primary cultures of feline corneal epithelial cells were grown after the addition of 102 to 106 IU of IFN-α/mL. Cultures were examined every 24 hours for evidence of cytotoxic changes. Viable cell counts and percentage of viable cells were determined 48 hours after initiation of culture. In a separate experiment, cultures of corneal cells were inoculated with FHV-1 and cultured for 72 hours with or without 105 IU of IFN-α/mL. The FHV-1–infected cultures were evaluated for viral-induced cytopathic effects, and viral titers were determined in samples of culture supernatant.
Results—Interferon-α did not have cytotoxic effects on corneal epithelial cells at concentrations ranging from 102 to 106 IU of IFN-α/mL. Interferon-α at a concentration of 105 IU/mL significantly reduced the cytopathic changes and FHV-1 titers.
Conclusions and Clinical Relevance—Lack of in vitro cytotoxic effects and efficacy against FHV-1 infection in primary cultures of feline corneal cells suggests that the in vivo therapeutic effect of IFN-α should be assessed in controlled clinical trials. (Am J Vet Res 2005;66:210–216)