Novel heparan sulfate-binding peptides for blocking herpesvirus entry

Area of Science:

• Virology
• Molecular Biology
• Drug Discovery

Background:

• Human cytomegalovirus (HCMV) causes significant congenital disabilities and severe illness in immunocompromised individuals.
• Current treatments for HCMV, like nucleoside analogues, have limited efficacy and severe toxicities.
• Cell-surface heparan sulfate proteoglycans (HSPGs) are crucial for HCMV and other herpesvirus entry into host cells.

Purpose of the Study:

• To identify and characterize synthetic heparin-binding peptides with antiviral activity against CMV.
• To investigate the mechanism by which the peptide p5+14 inhibits CMV infection.
• To evaluate the broad-spectrum antiviral potential of p5+14 against other herpesviruses.

Main Methods:

• Screening of synthetic heparin-binding peptides for in vitro inhibition of murine CMV (MCMV) infection.
• Assessing the effect of peptide p5+14 on viral adsorption to cell surfaces.
• Testing the antiviral activity of p5+14 against HCMV, herpes simplex virus 1 (HSV-1), and HSV-2 in vitro.

Main Results:

• Peptide p5+14 demonstrated approximately 90% reduction in MCMV infection.
• Positively charged lysine residues in p5+14 were essential for binding to HSPGs and inhibiting infection.
• p5+14 blocked viral adsorption without directly neutralizing the virus.
• The peptide exhibited broad-spectrum activity, inhibiting HCMV, HSV-1, and HSV-2 in vitro.

Conclusions:

• Peptide p5+14 effectively inhibits CMV and other herpesvirus infections by preventing viral attachment to cell-surface HSPGs.
• The mechanism involves competition for HSPG binding sites, crucial for viral entry.
• p5+14 represents a potential adjunct therapy for herpesviral infections, offering a novel approach beyond current treatments.