Studies on preparation and immunogenicity of Streptococcus pneumoniae type 2 polysaccharide-tetanus toxoid conjugate vaccine

Objective To prepare Streptococcus pneumoniae type 2 polysaccharide(SPNPS2)-tetanus toxoid(TT)conjugate vaccine(SPNPS2-TT)and study its immunogenicity.Methods The SPNPS2 was activated by cyanogen bromide.With adipic acid dihydrazide as linking agent,the SPNPS2-TT was prepared by carbodiimide-mediated coupling of SPNPS2 with TT.The Balb/c mice were immunized with SPNPS2-TT or pure SPN PS2,and the anti-SPNPS2 antibodies were detected by ELISA.Results All the qua-lity indexes of SPNPS2-TT met the standards of quality control.The levels of specific IgG antibody elicited in the mice immunized with SPNPS2-TT were significantly higher than those in the mice immunized with pure SPNPS2,and only SPNPS2-TT induced immune memory.Conclusion The SPNPS2-TT is successfully prepared with this technology. Key words: Streptococcus pneumoniae; Vaccine,conjugate; Polysaccharides,bacterial; Tetanus toxoid