Improvement of RBD-FC Immunogenicity by Using Alum-Sodium Alginate Adjuvant Against SARS-COV-2.

Area of Science:

• Vaccinology
• Immunology
• Biotechnology

Background:

• Adjuvants enhance vaccine immunogenicity by modulating immune responses.
• Antigen adsorption strength to adjuvants is crucial for improved immunopotentiation.

Purpose of the Study:

• To evaluate the efficacy of sodium alginate and aluminum hydroxide (alum) as adjuvants in a recombinant RBD-FC vaccine formulation.
• To assess the impact of these adjuvants, alone and in combination, on vaccine immunogenicity and antigen stability.

Main Methods:

• Recombinant RBD-FC was expressed and formulated with sodium alginate and alum.
• Mice were vaccinated with different adjuvant formulations.
• Immunogenicity was assessed using serological assays like ELISA and surrogate virus neutralization tests (sVNT).
• Cytokine levels (IL-10, INF-γ, IL-4) were measured.

Main Results:

• Sodium alginate significantly increased RBD-FC antigen immunogenicity and stability.
• The RBD-FC:AlSa (alginate and alum combined) formulation induced higher antibody titers and stability.
• High levels of IgG and neutralizing antibodies were observed in immunized mice.
• Specific cytokine profiles (IL-10, INF-γ, IL-4) were modulated by the adjuvant formulations.

Conclusions:

• The combination of alum and sodium alginate demonstrates superior compatibility with RBD-FC in vaccine formulations.
• This combined adjuvant approach shows promise for enhancing vaccine effectiveness.