Mannosylated niosomes as carrier adjuvant system for topical immunization

Area of Science:

• Nanotechnology
• Immunology
• Vaccine Delivery

Background:

• Developing effective topical vaccine delivery systems is crucial for enhancing immune responses.
• Niosomes offer a promising platform for drug and vaccine delivery.
• Targeting antigen-presenting cells, like Langerhan's cells, can improve vaccine efficacy.

Purpose of the Study:

• To develop mannosylated niosomes as a topical vaccine carrier and adjuvant.
• To evaluate the ability of these niosomes to induce humoral and cellular immunity.
• To assess the potential of OPM-coated niosomes for clinical applications.

Main Methods:

• Niosomes were prepared using the reverse-phase evaporation method with specific lipids.
• Niosomes were coated with O-palmitoyl mannan (OPM) for targeted delivery.
• In-vitro characterization and in-vivo immune response studies (serum IgG titre) were performed in rats.

Main Results:

• Mannosylated niosomes showed significantly higher serum IgG titres compared to topical alum-adsorbed BSA.
• Topical application of mannosylated niosomes induced significantly higher IgG levels than plain niosomes.
• Formulations demonstrated a combined IgG2a/IgG1 response, indicating both humoral and cellular immunity induction.

Conclusions:

• OPM-coated niosomes are effective topical vaccine delivery carriers and adjuvants.
• The proposed system is simple, stable, cost-effective, and potentially clinically acceptable.
• Mannosylated niosomes enhance both humoral and cellular immune responses upon topical application.