Inhibition of Herpes Simplex Virus Type 1 Infection by Cationic β-Peptides

Abstract

ABSTRACT Previously, it was shown that cationic α-peptides derived from the human immunodeficiency virus TAT protein transduction domain blocked herpes simplex virus type 1 (HSV-1) entry. We now show that cationic oligomers of β-amino acids (“β-peptides”) inhibit HSV-1 infection. Among three cationic β-peptides tested, the most effective inhibition was observed for the one with a strong propensity to adopt a helical conformation in which cationic and hydrophobic residues are segregated from one another (“globally amphiphilic helix”). The antiviral effect was not cell type specific. Inhibition of virus infection by the β-peptides occurred at the postattachment penetration step, with a 50% effective concentration of 3 μM for the most-effective β-peptide. The β-peptides did not inactivate virions in solution, nor did they induce resistance to infection when cells were pretreated with the β-peptides. The β-peptides showed little if any toxicity toward Vero cells. These results raise the possibility that cationic β-peptides may be useful antiviral agents for HSV-1 and demonstrate the potential of β-peptides as novel antiviral drugs.