Beijing Luzhu Biopharmaceutical Co., Ltd.

Objective To observe the immunogenicity and immune persistence of groups A&C meningococcal polysaccharide conjugate vaccine in infants at various ages.Methods A total of 1 190 infants in Long'an County, Nanning City, Guangxi Zhuang Autonomous Region, China were divided into three age groups, i.e. 3-8 mo (220 in trial and 133 in control groups), 1-2 years (202 in trial and 212 in control groups) and 3-4 years (218 in trial and 205 in control groups).The infants in trial groups were injected i.m. with groups A&C meningococcal polysaccharide conjugate vaccine, while those in control groups with groups A&C meningococcal polysaccharide vaccine.The infants at ages of 3-8 mo were immunized for 3 times, while those at ages of 1-2 years for 2 times, each at an interval of one month, and those at ages of 3-4 years with a single dose.The dosage of vaccine was 0.5 mL.Serum samples were collected before immunization, 4 wk after the second dose, 4 wk after the third dose and 3 years after the last dose in the infants at ages of 3-8 mo, before immunization, 4 wk after the second dose and 3 years after the last dose in those at ages of 1-2 years, and before and 4 wk and 3 years after immunization in those at ages of 3-4 years, determined for antibody level by bactericidal test and ELISA, and observed for immune effect and change of antibody level as time went on.Results The antibody levels of infants at various ages increased significantly after immunization with groups A&C meningococcal polysaccharide conjugate vaccine, and were persistent 3 years after immunization.Conclusion Groups A&C meningococcal polysaccharide conjugate vaccine induced and maintained antibodies at immune protection levels in infants at various ages.

A review.Due to the excellent safety and efficacy data, conjugate vaccine has become a direction for bacterial vaccine development, but different conjugate technologies from different independent research groups also brought some confusion.After reviewing the research history of some representative team, conjugate methods, carrier protein, vaccine formulation and other hot topics were discussed.

Objective To investigate the application of NMR (NMR) spectrum in preparation of bivalent Shigella conjugate vaccine.Methods Using Agilent 600 MHz NMR spectrometer, the repeating structural units of S. flexneri 2a polysaccharide and S. sonnei polysaccharide were analyzed by ¹H NMR and ¹³C NMR, while those of polysaccharides, derivatives and conjugates in production procedure were analyzed by ¹H NMR.Results The ¹H NMR and ¹³C NMR data and spectrums of Shigella polysaccharides were highly consistent with those in documents.The anal. of polysaccharides in production procedure by ¹H NMR proved the reaction mechanism of the procedure.Conclusion In the development of bivalent Shigella conjugate vaccine, NMR spectrum may be used for the direct determination of chem. structure of polysaccharide as well as the quality control of structure and modification level of polysaccharide as a raw material during derivation.