Serogroup quantitation of multivalent polysaccharide and polysaccharide-conjugate meningococcal vaccines from China

Method development and validation of unbound saccharide content (serogroup A, C, Y, W, X) in novel pentavalent meningococcal polysaccharide conjugate vaccine with two different carrier proteins

Exclusive DOC-HCl formulations were developed for free polysaccharide content estimation in Meningococcal serogroup A, C, Y, W and X from pentavalent meningococcal vaccine (A, C, Y, W, X). The DOC precipitation method reported herein stands as an alternative to the ultra-filtration method for free polysaccharide estimation. DOC content was optimized for all the serogroups at a single concentration, where as effective acid concentration was altered as per serogroup. Briefly, two DOC-HCl formulations were developed for intended purpose, one for TT conjugated serogroups Men A & Men X where as other for CRM conjugated serogroups Men C, Men Y and Men W with effective HCl concentration of 23 mM and 193 mM for precipitation of Protein-DOC complex respectively. Furthermore, an exclusive buffer/DOC-HCl formulation for estimation of Men X free polysaccharide in fill finished product was developed. Accuracy of the method was proven at 12.5 %, 25 %, 50 % and 100 % of test specification where recoveries were found in the range of 70-130 %. In case of repeatability, intra assay variation ranged from 2 % to 7 % whereas inter assay variation was noted to be 2-14 %. Specificity studied revealed no interference of assay components such as sample excipients, DOC, acids. Critical quality and stability-indicating characteristics were measured. Monovalent polysaccharide standards of Men A, C, Y, W and X were developed and assigned the unitage concentration 1.01, 1.10, 1.09, 1.08 and 1.00 mg/mL respectively. Linearity curve was optimized from 0.17 to 27 µg/mL for Men A and C whereas from 0.33 to 27 µg/mL for Men Y and W considering free polysaccharide content estimation. The study suggests that DOC-HCl method meets all the criteria for free polysaccharide estimation in multivalent vaccines with additional advantages of high throughput and sized independent separation hence can be used for quality control testing.

Vaccine Quality Ensured by High-Performance Anion-Exchange Chromatography with Pulsed Amperometric Detection

Many important vaccines use bacterial capsular polysaccharides, or shorter polysaccharides or oligosaccharides, derived from the capsular polysaccharides, conjugated to protein. It is imperative that manufacturers understand the carbohydrate composition of these vaccines and deliver a product with a consistent polysaccharide or polysaccharide conjugate composition and content. High-performance anion-exchange chromatography with pulsed amperometric detection (HPAE-PAD) is a major technique used to understand the carbohydrate composition of these vaccines and ensure product quality. HPAE-PAD separates and detects carbohydrates without analyte derivatization. This paper describes the basics of the HPAE-PAD technique and then reviews how it has been applied to Haemophilus influenzae type b, pneumococcal, meningococcal, group B streptococcal, and Salmonella polysaccharide and corresponding conjugate vaccines.

Monoclonal Antibodies Against the Capsular Polysaccharides A, C, Y, W, and X of Neisseria meningitidis: A Platform for the Quality Control of Meningococcal Vaccines

Vaccination has reduced morbidity and mortality of many diseases that previously caused devastating epidemics and deaths globally. Vaccines as a biological product may contain microorganisms or their derivatives. This aspect together with the fact that they are administered to healthy individuals (mainly children) means that approximately 70% of vaccines development time is dedicated to quality control. Monoclonal antibodies (MAbs) have become essential analytical tools for application in ELISAs, Western and Dot blotting, immunoprecipitation, and flow cytometric assays that ensure the quality control of vaccines. The aim of this work is to present a review of the methods used to obtain a platform of MAbs against Neisseria meningitidis polysaccharide antigens to use as an analytical tool for quality control of anti-meningococcal polysaccharide (Ps) vaccines. The MAbs obtained are used in five sandwich ELISAs developed for Ps quantification. The assays showed good reproducibility and repeatability, with quantitation and detection limits below 1 ng/mL. Dot Blot, as the Identity test of the Ps vaccine, was carried out to positively identify licensed and experimental vaccines. All assays described are suitable for the screening of multiple vaccine samples and could be useful for monitoring lot-to-lot consistency and stability.

A novel monoclonal antibody to Neisseria meningitidis serogroup X capsular polysaccharide and its potential use in quantitation of meningococcal vaccines

A novel murine hybridoma monoclonal antibody (MAb) was produced against the capsular polysaccharide (CP) of Neisseria meningitidis serogroup X (MenX) in order to develop a sandwich enzyme linked immunosorbent assay (ELISA) for the quantitation of the meningococcal polysaccharide. The MAb only reacted with the CP from MenX and did not react with CPs from N. meningitidis serogroups A, C, Y and W (MenA, MenC, MenY, MenW). The affinity constant (Ka) of the MAb measured by non-competitive ELISA was 7.25 × 10(7) M(-1). The application of this MAb in a sandwich ELISA was demonstrated by its ability to properly quantitate three lots of an experimental meningococcal CP-based vaccine. The MAb obtained in this work could be a valuable reagent for the detection and quantitation of future meningococcal vaccines containing MenX CP.