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Objective To compare the adjuvant activity of oil-in-water emulsion MF59 and aluminum hydroxide on immune responses to HIV-1 multi-epitope protein MEP1 in BALB/c mice. Methods HIV-1 multi-epitope protein MEP1 with MF59 or aluminum was prepared to intramuscularly vaccinate female BALB/c mice for three times. Serum and splenocytes were isolated from the mice 10 d after the first and last vaccination. Specific anti-MEP1 antibodies and the subclasses in serum were detected by ELISA. The num-bers of splenic lymphocytes secreting IFN-γ and IL-4 were measured by ELISPOT. Differences in humoral and cellular immune responses induced by the two different adjuvants were compared. Results After a sin-gle-dose immunization, aluminum adjuvant promoted early humoral and cellular immune responses to MEP1 compared with MF59. After the three-dose immunization, both aluminum adjuvant and MF59 promoted MEP1 to induce Th2-biased humoral immune response, while MF59 also enhanced a balanced Th1/Th2 cel-lular immune response. Conclusions Aluminum adjuvant was a more suitable adjuvant than MF59 for HIV-1 multi-epitope protein MEP1.
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Objective To evaluate the immunostimulatory effects of polysaccharides, including Lycium barbarum polysaccharides ( LBP) , Angelica polysaccharides ( AP) , Licorice polysaccharides ( LP) and Inulin polysaccharides ( IP) , used alone or in combination with aluminum adjuvant on the recombinant protein of varicella-zoster virus (VZV) glycoprotein (gE) as an immunogen in mice. Methods BALB/c mice were randomly divided into 11 groups with five in each group. Intramuscular injection was given at Days 0 and 14. Serum samples were collected at weeks 0, 2, 3, 4 and detected for total anti-gE IgG titers and an-tibody subtypes by indirect ELISA. The mice were sacrificed at week 4 to collect spleen lymphocytes aseptic-ally. CCK-8 method was used to evaluate the proliferation of spleen lymphocytes. The levels of IFN-γ and IL-4 were measured by ELISA. The percentages of CD3+CD4+ and CD3+CD8+ T cell subsets were deter-mined by flow cytometry. Results The four plant-derived polysaccharides in combination with aluminum adjuvant showed good adjuvant activities. LP combined with aluminum adjuvant effectively increased the titer of IgG2, promote the proliferation of splenocytes and enhanced the secretion of IFN-γ and IL-4. Further-more, it also induced CD3+CD4+ and CD3+CD8+ T cell proliferation in vivo. Conclusions The four plant-derived polysaccharides in combination with aluminum adjuvant could all enhance antibody production. LP combined with aluminum adjuvant could induce cell-mediated immune responses, suggesting that it might be a promising adjuvant for varicella-zoster subunit vaccines.
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Objective To evaluate the immunopotentiating effect of cyclic guanosine monophos-phate-adenosine monophosphate (cGAMP) as an adjuvant on norovirus (GⅡ. 4) virus like particles (VLPs) in the development of norovirus vaccine. Methods BALB/c mice were intramuscularly immunized with norovirus (GⅡ.4) VLPs composed of capsid protein VP1 in combination with cGAMP or Al(OH)3. Norovirus VLPs-specific antibodies in serum were detected by ELISA. A synthetic histo-blood group antigen (HBGA)-VLPs blocking assay was used to analyze neutralizing antibodies against norovirus VLPs in serum samples. Results Immunization with norovirus VLPs in the presence of cGAMP induced a strong humoral immune response in BALB/c mice. Levels of specific IgG antibodies in serum induced by using cGAMP as the adjuvant were significantly higher than those induced by using Al(OH)3adjuvant when immunization of BALB/c mice with the same dosage of VLPs. The antibody level induced by 1 μg of VLPs in combination with cGAMP was equivalent to that elicited by 10 μg of VLPs combined with Al(OH)3adjuvant. Results of the synthetic HBGA-VLPs blocking assay showed that the blocking rate in cGAMP+VLPs immunization group were significantly higher than that in Al(OH)3+VLPs immunization group when using the same dosage of VLPs. No significant difference in blocking rate was observed between cGAMP+VLPs(1 μg) and Al(OH)3+VLPs (10 μg) immunization groups. Conclusion cGAMP significantly enhanced the specific humoral immune response induced by norovirus (GⅡ.4) VLPs in mice as compared with Al(OH)3adjuvant. It might be used as a novel adjuvant to replace the traditional aluminum adjuvant in the development of norovir-us vaccine.
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Objective:To prepare Streptococcus pneumonia type 3 capsular polysaccharide conjugate vaccine.Methods:Strep-tococcus pneumonia type 3 capsular polysaccharide was covalently linked to protein CRM197 and its immunogenicity was evaluated in infant mice.Results:Through the preliminary research, we found that the polysaccharide was treated with 0.2 mol/L acetic acid at 85℃ for 1 h,activation grade reached to 10.0,and the radio of polysaccharide and protein was 20∶10,could induce infant mice to produce the high titers of antibodies.Conclusion:This result shows that conjugate vaccine prepared under this condition retained intact antigenicity.It is applicable to prepare Streptococcus pneumonia type 3 capsular polysaccharide conjugate vaccine by the process condi-tions.