Anti-adenoviral effect of interferon-β and interferon-γ in serotypes that cause acute keratoconjunctivitis.

BACKGROUND

Interferons are currently used for hepatitis B and C virus infection; the effect of interferons against adenovirus has not been elucidated. It has been reported that interferon-β and interferon-γ were effective against adenovirus serotype 3. We investigated the anti-adenoviral effect of interferon-β and interferon-γ in serotypes that cause acute keratoconjunctivitis, using quantitative polymerase chain reaction in vitro.

DESIGN

Experimental study carried out in a university.

SAMPLES

Five strains of different serotypes of adenovirus, types 3 (AdV3; species B), 4 (species E), 8, 19a and 37 (species D) and interferon-β and interferon-γ for in vitro assay.

METHODS

After pretreatment of A549 with serial dilution of interferons for 24 h, adenovirus was cultivated for 7 days, and adenoviral DNA was quantitatively measured by real-time polymerase chain reaction.

MAIN OUTCOME MEASURES

Number of virus copies after treatment and the 50% effective concentration (EC(50) ).

RESULTS

Interferon-β showed a dose-dependent inhibitory effect on all serotypes. EC(50) of interferon-β ranged between 211 and 843 IU/mL. A similar tendency was observed with interferon-γ. EC(50) of interferon-γ ranged between 133 and 9130 IU/mL. Among the serotypes, interferon-γ exhibited the greatest inhibitory effect on AdV37. In contrast, AdV4 showed the lowest sensitivity to interferon-γ. Statistically significant dose dependency for both interferon-β and interferon-γ was observed in several serotypes.

CONCLUSIONS

These results suggest that both interferon-β and interferon-γ have anti-adenoviral activity in vitro. Interferons have the potential to be used for local treatment of adenoviral keratoconjunctivitis, although further evaluation in animal models and clinical trials is necessary.