Efficient oral vaccination by bioengineering virus-like particles with protozoan surface proteins

Area of Science:

• Parasitology
• Immunology
• Vaccinology

Background:

• Protozoa like Giardia lamblia use variant-specific surface proteins (VSPs) for protection.
• VSPs exhibit resistance to harsh conditions and modulate host immune responses via TLR-4.
• These VSP properties present an opportunity for developing oral vaccine adjuvants and delivery systems.

Purpose of the Study:

• To investigate the potential of VSPs as protective and adjuvant components for oral vaccines.
• To develop and evaluate chimeric virus-like particles (VLPs) decorated with VSPs for antigen delivery.
• To assess the immunogenicity and protective efficacy of VSP-pseudotyped VLPs against influenza and tumors.

Main Methods:

• Constructed chimeric VLPs displaying VSPs and model antigens (influenza HA and NA).
• Assessed VLP stability against degradation and their ability to activate antigen-presenting cells in vitro.
• Administered VSP-pseudotyped VLPs orally to mice and evaluated immune responses and protection against influenza infection and tumors.

Main Results:

• VSP-decorated VLPs demonstrated resistance to degradation and activated antigen-presenting cells.
• Oral administration of VSP-pseudotyped VLPs induced robust immune responses in mice.
• Mice vaccinated with VSP-VLPs were protected from influenza infection and showed reduced growth of HA-expressing tumors.

Conclusions:

• VSPs can be leveraged to create stable and immunogenic oral vaccine platforms.
• VSP-pseudotyped VLPs represent a promising strategy for developing safe and effective oral vaccines.
• This versatile platform demonstrates potential for combating infectious diseases and cancer.