Related Experiment Video
Updated: Dec 30, 2025
An Improved and High Throughput Respiratory Syncytial Virus RSV Micro-neutralization Assay
Published on: January 26, 2019
Structure-Guided Improvement of a Dual HPIV3/RSV Fusion Inhibitor
Victor K Outlaw1, Jennifer T Lemke1, Yun Zhu2,3
1Department of Chemistry , University of Wisconsin , Madison , Wisconsin 53706 , United States.
Abstract:
Human parainfluenza virus 3 (HPIV3) and respiratory syncytial virus (RSV) are leading causes of lower respiratory tract infections. There are currently no vaccines or antiviral therapeutics to treat HPIV3 or RSV infections. We recently reported a peptide (VIQKI), derived from the C-terminal heptad repeat (HRC) domain of the HPIV3 fusion (F) glycoprotein that inhibits infection by both HPIV3 and RSV. The dual inhibitory activity of VIQKI is due to its unique ability to bind to the N-terminal heptad repeat (HRN) domains of both HPIV3 and RSV F, thereby preventing the native HRN-HRC interactions required for viral entry. Here we describe the structure-guided design of dual inhibitors of HPIV3 and RSV fusion with improved efficacy. We show that VIQKI derivatives possessing one (I456F) or two (I454F/I456F) phenylalanine substitutions near the N-terminus exhibit more stable assemblies with the RSV-HRN domain and enhanced antiviral efficacy against both HPIV3 and RSV infection. Cocrystal structures of the new Phe-substituted inhibitors coassembled with HPIV3 or RSV-HRN domains reveal that the I456F substitution makes intimate hydrophobic contact with the core trimers of both HPIV3 and RSV F.
Insights
New peptide derivatives show enhanced efficacy against human parainfluenza virus 3 (HPIV3) and respiratory syncytial virus (RSV) infections. These dual inhibitors target the fusion glycoproteins, offering a promising strategy for treating these common respiratory illnesses.
Area of Science:
- Virology
- Structural Biology
- Drug Discovery
Background:
- Human parainfluenza virus 3 (HPIV3) and respiratory syncytial virus (RSV) are major causes of severe respiratory infections.
- Current treatments for HPIV3 and RSV are limited, with no existing vaccines or antiviral therapies.
Purpose of the Study:
- To design and develop novel peptide inhibitors targeting both HPIV3 and RSV fusion glycoproteins.
- To improve the efficacy and stability of previously identified dual inhibitors.
Main Methods:
- Structure-guided design of peptide inhibitors based on the HPIV3 fusion glycoprotein.
- Introduction of phenylalanine substitutions into the VIQKI peptide sequence.
- Crystallographic analysis of inhibitor-fusion protein domain complexes.
- Antiviral assays to evaluate efficacy against HPIV3 and RSV infection.
Main Results:
- VIQKI peptide derivatives with phenylalanine substitutions demonstrated enhanced antiviral activity against HPIV3 and RSV.
- The I456F and I454F/I456F substitutions led to more stable interactions with the viral fusion protein domains.
- Cocrystal structures revealed specific hydrophobic interactions contributing to the enhanced binding and inhibition.
Conclusions:
- Structure-guided modifications of the VIQKI peptide significantly improve its dual inhibitory potential against HPIV3 and RSV.
- The developed phenylalanine-substituted inhibitors represent a promising therapeutic strategy for combating HPIV3 and RSV infections.
Related Concept Videos
01:22Healthcare Associated Infections II: Preventive Measures
The best practices for preventing healthcare-associated infections include hand hygiene, patient risk...
01:18Endocarditis III: Medical Management
01:29Endocarditis IV: Nursing Management
01:23Treatment for Pulmonary Arterial Hypertension: Prostacyclin Receptor Agonists
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...
01:28Pneumonia IV: Management
Bacterial Pneumonia Treatment
For bacterial pneumonia, antibiotics serve as the cornerstone of therapy. Initial treatment often begins with empirical antibiotics, tailored to the anticipated causative organism and adjusted based on culture results. Key antibiotic choices include:
01:24Drug Accumulation During Multiple Dosing: Intermittent IV Infusions