Immune responses to HIV-1 polytope vaccine candidate formulated in aqueous and alcoholic extracts of Propolis: Comparable immune responses to Alum and Freund adjuvants

• Published in: Microbial pathogenesis 2020-03, Vol.140, p.103932-103932, Article 103932
• Main Authors: Mojarab, Sanaz, Shahbazzadeh, Delavar, Moghbeli, Majid, Eshraghi, Yasaman, Bagheri, Kamran Pooshang, Rahimi, Roghieh, Savoji, Mohammad Ali, Mahdavi, Mehdi
• Format: Article
• Language: English
• Subjects: Adjuvant; Alcoholic extracts; Aqueous extract; Multi-epitope HIV-1 vaccine; Propolis
• ISSN: 0882-4010; 1096-1208
• DOI: 10.1016/j.micpath.2019.103932

Today's, vaccination is the most cost-effective approaches for preventing infectious diseases. In this strategy, adjuvants play an important role. Propolis from honey bee can stimulate the immune system and several studies have shown the modulating effects of Propolis on the immune responses. Here, the adjuvant effects of aqueous and alcoholic extracts of Propolis were studied on the multi-epitope vaccines against HIV-1. A recombinant vaccine against HIV-1 was prepared and BALB/c mice were immunized. subcutaneously on day 0 with 100 μl of candidate vaccine (10 μg) formulated in an alcoholic extract of Propolis. The second group of mice was immunized with the vaccine (10 μg) formulated in aqueous extract of Propolis. Also, candidate vaccine was formulated in Freund's and Alum adjuvants in the third and fourth groups. Experimental mice were immunized three times with two week intervals under the same conditions and suitable control groups. After final injection, lymphocyte proliferation was measured by BrdU method, IL-4 and IFN-γ cytokines, specific total IgG antibodies, IgG1 and IgG2a isotypes were evaluated using ELISA. The results show that the aqueous and alcoholic extracts were able to enhance lymphocyte proliferation, IL-4 and IFN-γ cytokines and antibody responses with dominant IgG1 pattern and comparable to Freund's and Alum adjuvants. It seems that aqueous and alcoholic extracts of Propolis show adjuvant activity and may be useful for vaccine formulation. •Aqueous and alcoholic extracts of Propolis induced lymphocyte proliferation like to Alum and Freund adjuvanted vaccines.•Propolis extracts induced IFN-γ and IL-4 cytokines, comparable to vaccine formulated in Alum and Freund adjuvants.•Alcoholic extract induced humoral immune response comparable to Alum and Freund adjuvanted vaccines.•Biomolecules from aqueous and alcoholic extracts of Propolis may be useful as a part of complex adjuvants.