Evaluation of effect of CpG adjuvant on the immunogenicity of acellular pertussis vaccine
10.13200/j.cnki.cjb.004696
- VernacularTitle:CpG佐剂对无细胞百日咳疫苗免疫原性影响的评价
- Author:
Yun ZENG
- Publication Type:Journal Article
- Keywords:
CpG;
Novel adjuvant;
Pertussis vaccine;
Humoral immunity;
Cellular immunity
- From:
Chinese Journal of Biologicals
2026;39(05):534-539
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo investigate the effect of the novel adjuvant CpG on the immune response to a component acellular pertussis vaccine(aPV) in mice.MethodsVaccine formulations were prepared with either aluminum hydroxide adjuvant alone or a composite adjuvant containing CpG plus aluminum hydroxide, each adsorbed with high and low doses of pertussis toxoid(PTd), filamentous hemagglutinin(FHA) and pertactin(PRN) antigens. For immunogenicity assessment, five female CD1 mice were immunized intraperitoneally on day 0. Serum was collected on day 28 to measure antigen-specific antibody levels against PTd, FHA and PRN. In a separate experiment to assess antibody isotypes, five female CD1 mice were immunized intraperitoneally on day 0 and given a booster on day 14. Serum was collected on day 28 to measure IgG1 and IgG2a antibody titers. Twenty NIH mice were immunized by intraperitoneal injection, half male and half female. Vaccine efficacy was assessed using the mice challenged intracerebrally with Bordetella pertussis(8 × 10~4/0. 03 mL) 21 days postimmunization. The survival of mice was recorded over a 14-day observation period, and the qualitative reaction parallel line method were used to calculate the vaccine titers.ResultsIn the low-dose composite adjuvant group, the serum levels of antiPTd, anti-FHA, and anti-PRN specific antibodies in mice were all elevated compared to the single adjuvant group(P =0. 038 9, 0. 002 1 and 0. 008 9, respectively), while in the high-dose composite adjuvant group, only the anti-PRN specific antibody level increased(P = 0. 017 9). The PTd-, FHA-, and PRN-specific antibody IgG1/IgG2a ratios in both the low-and high-dose composite adjuvant groups were significantly lower than those in the single adjuvant group(P = 0. 036 9 and0. 003 0, 0. 012 5 and 0. 003 6, 0. 017 5 and 0. 032 5, respectively), suggesting a shift in the immune response from a Th2-biased to a Th1-biased cellular immune response. The composite adjuvant formulation could enhance the potency of the component aPV.ConclusionThe CpG adjuvant can enhance the humoral immune response and induce a cellular immune response to the component pertussis vaccine, thereby improving its protective potency, which suggests its potential application in booster vaccines for adolescents and adults, such as DTaP.
