The amphibian antimicrobial peptide temporin B inhibitsin vitroherpes simplex virus type 1 infection

The herpes simplex virus type 1 (HSV-1) is widespread in the population and in most cases its infection is asymptomatic. The currently available anti-HSV-1 drugs are acyclovir and its derivatives, although long-term therapy with these agents can lead to drug resistance. Thus, the discovery of novel anti-herpetic compounds deserves additional effort. Naturally occurring antimicrobial peptides (AMPs) represent an interesting class of molecules with potential antiviral properties. To the best of our knowledge this work is the first demonstration of thein vitroanti-HSV-1 activity of Temporin B (TB), a short membrane-active amphibian AMP. In particular, when HSV-1 was pre-incubated with 20 μg/ml TB, significant antiviral activity (5 log reduction of viral titer) was observed. Such an effect was due to the disruption of the viral envelope, as demonstrated by transmission electron microscopy. Moreover, TB partially affected different stages of HSV-1 life cycle, including the attachment, the entry of the virus into the host cell as well as the following post infection phase. Furthermore, its efficacy was confirmed on human epithelial cells, thus suggesting TB as a novel approach for the prevention and/or treatment of HSV-1 infections.