Re-evaluation of the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population aged 5 to 59
10.3760/cma.j.issn.0254-5101.2014.03.015
- VernacularTitle:A群C群脑膜炎球菌多糖疫苗对5～59岁健康人群的免疫原性再评价
- Author:
Zhiqiang ZHAO
;
Ruijie QIAO
;
Xinru WANG
;
Hao WANG
;
Jin YANG
;
Yi QUAN
;
Xiaoling SHI
;
Jia LIU
;
Jisheng LIN
;
Guilin XIE
- Publication Type:Journal Article
- Keywords:
Meningococcal serogroups A and C polysaccharide vaccine;
Immuogenicity;
Enzyme-linked immunosorbent assay (ELISA);
Serum bactericidal assay ( SBA)
- From:
Chinese Journal of Microbiology and Immunology
2014;(3):228-234
- CountryChina
- Language:Chinese
-
Abstract:
Objective To re-evaluate the immunogenicity of meningococcal serogroups A and C polysaccharide vaccine among a healthy population of age 5 to 59.Methods Pre and post-vaccination ser-um samples were collected from the subjects involved in a randomized , controlled clinical trial conducted in 2005 at Hechi, Guangxi, China.Enzyme-linked immunosorbent assay (ELISA) was performed for the quan-titative detection of specific anti-capsule IgG antibody against meningococcal serogroups A and C in serum samples.Serum bactericidal assay ( SBA) was used to measure the bactericidal antibody activity against se-rougroups A and C bacterial strains .Results Geometric mean concentrations (GMCs) of specific anti-cap-sule IgG antibody were 23.66 μg/ml and 78.83 μg/ml for serogroup A (P<0.05), and 1.23 μg/ml and 51.25 μg/ml for serogroup C (P<0.05) in serum samples of pre and post-vaccination, respectively.Be-fore immunization , 99% of serum samples ( 97/98 ) showed serogroup A-specific IgG concentration ≥2μg/ml, which reached up to 100%(98/98) after vaccination (P>0.05).The percentage of serum sam-ples with serogroup C-specific IgG concentration ≥2 μg/ml rose from 20%to 99% after vaccination ( P<0.05).The ratio of positive serum samples with at least four times of increases in concentration of specific IgG against serogroup A and serogroup C after vaccine immunization were 34% and 100%, respectively . The rSBA geometric mean titers ( GMTs) for serogroups A and C in serum sample of post-vaccination were respectively elevated from 1164 to 5530 (P<0.05), and from 4 to 6225 (P<0.05).The percentage of se-rum samples with rSBA GMTs≥128 increased from 91% to 99% for serogroup A (P>0.05), and from 14%to 96%for serogroup C (P<0.05) after vaccination.The rSBA GMTs with at least four times of in-creases after vaccination were detected respectively in 53% and 100% of serogroups A and C vaccinated subjects.Pearson correlation coefficient between IgG concentration and rSBA GMTs was r=0.15 (pre) and r=0.23 (post) for serogroup A, and r=-0.14 (pre) and r=0.58 (post) for serogroup C (P<0.05). Conclusion This study has demonstrated an efficient and sustained immunogenicity with meningococcal sero -groups A and C polysaccharide vaccine as evidenced by the data from standardized assays of ELISA and SBA .
