Norwalk virus-like particles as vaccines

Area of Science:

• Virology
• Vaccinology
• Biotechnology

Background:

• Noroviruses (NoV) are a leading cause of epidemic nonbacterial gastroenteritis in humans.
• Recombinant expression of norovirus capsid proteins yields virus-like particles (VLPs) that mimic authentic virions.
• Norwalk virus-like particles (NVLPs) are acid- and heat-stable, and immunogenic.

Purpose of the Study:

• To evaluate the potential of norovirus VLPs as vaccine-delivery vehicles.
• To investigate the immunogenicity of NVLPs via oral and nasal delivery.
• To explore the feasibility of using NVLPs for delivering heterologous peptide antigens.

Main Methods:

• Expression of norovirus capsid proteins in insect and plant cells to produce VLPs.
• Oral and intranasal administration of NVLPs in mice and humans.
• Analysis of systemic and mucosal antibody responses.
• Identification of potential sites for foreign peptide insertion on VLP surface structures.

Main Results:

• NVLPs produced in insect cells and plants are immunogenic in mice and humans upon oral delivery.
• Intranasal delivery of NVLPs elicits high antibody levels at lower doses compared to oral delivery.
• Oral and nasal NVLP delivery stimulate antibodies at distal mucosal sites.
• Surface structure analysis identified suitable sites for foreign peptide insertion without compromising VLP assembly or receptor binding.

Conclusions:

• Norovirus VLPs, particularly NVLPs, are promising vaccine candidates due to their immunogenicity and stability.
• NVLPs can be effectively delivered orally and intranasally, inducing robust mucosal immunity.
• Norovirus VLPs have significant potential as versatile vaccine-delivery platforms for heterologous antigens.