Development of a New Solid-Phase Extraction Base Method for Free Saccharide Content Estimation of Meningococcal Conjugate Vaccines.

GlaxoSmithKline (GSK) is currently developing a fully liquid presentation to ease the administration of the licensed quadrivalent conjugate vaccine (Menveo) against meningococcal serogroup A, C, W, and Y (MenACWY) infections. Herein, we report a new method for determining the free saccharide (FS) content of CRM-MenACWY conjugated antigens, with the aim of improving accuracy and reproducibility. Mathematical models have been used to support technical knowledge in reducing the need for experimental development.

Clinically proven specification setting for a meningococcal serogroup a conjugate vaccine.

GSK is currently working to improve the commercial presentation of the licensed quadrivalent conjugate vaccine (Menveo) for use against meningococcal serogroup A, C, W, Y (MenACWY) infections. Menveo consists of a primary, lyophilized vial, containing the serogroup A antigen that is reconstituted with the content of a second, liquid, vial that contains the serogroup C, W, Y antigens, to give the final liquid MenACWY product. Since the MenA structure is prone to hydrolytic degradation in liquid formulations, we used mathematical models to rationally design a clinical Phase 2 development plan and provide end of shelf-life (EoSL) and release specification setting for the MenACWY liquid product.

Glycoconjugate content quantification to assess vaccine potency: A simplified approach.

Several glycoconjugate vaccines have been licensed or are currently in clinical development to prevent bacterial infections. Here we report the development of a single analytical assay to quantify the conjugated saccharide content, as alternative to two separated total and free (unconjugated) saccharide assays used so far, for a quadrivalent conjugate vaccine containing meningococcal serogroup A polysaccharide (α-1,6-linked N-acetylmannosamine phosphate repeating unit partly O-acetylated at position C or C) coupled with CRM protein. The results confirm a high linear correlation among the two approaches (conjugated saccharide content vs.

Structural organization of NadADelta(351-405), a recombinant MenB vaccine component, by its physico-chemical characterization at drug substance level.

The physico-chemical characterization of NadADelta(351-405), a recombinant protein discovered by reverse vaccinology, component of a candidate vaccine against Neisseria meningitidis serotype B is presented. Analytical methods like mass spectrometry, electrophoresis, optical spectroscopy and SEC-MALLS have been applied to unveil the structure of NadADelta(351-405), and to evaluate Product-Related Substances. Moreover, analysis of the protein after intentional denaturation has been applied in order to challenge the chosen methods and to determine their appropriateness and specificity.

Physicochemical characterisation of glycoconjugate vaccines for prevention of meningococcal diseases.

Bacterial capsular polysaccharides covalently linked to an appropriate carrier protein represent the best tool to induce a protective immune response against a wide range of bacterial diseases, such as meningococcal infections. We describe here the physico-chemical characterisation of glycoconjugate molecules designed to prepare a vaccine against Neisseria meningitidis serogroups A, C, W135 and Y. The use of a selective conjugation chemistry resulted in well characterised, reproducible and traceable glycoconjugate that can be consistently manufactured at large scale.

Size determination of bacterial capsular oligosaccharides used to prepare conjugate vaccines against Neisseria meningitidis groups Y and W135.

The glycoconjugate vaccines against Neisseria meningitidis groups Y and W135 consist of pools of selected oligosaccharides conjugated to the protein carrier (CRM197). Consistent production of these vaccines requires control and thus determination of the average degree of polymerisation of the oligosaccharides used for conjugation. Acid hydrolysis generates group Y and W135 oligosaccharides with N-acetylneuraminic acid at the reducing end.

Use of the RFLP-PCR diagnostic test for characterizing MACE and kdr insecticide resistance in the peach potato aphid Myzus persicae.

The peach-potato aphid Myzus persicae (Sulzer) has developed a number of insecticide resistance mechanisms owing to the high selective pressure produced by world-wide insecticide treatments. Knowledge of the geographical distribution and the temporal evolution of these resistant phenotypes helps to develop suitable pest-management programs. Current understanding of the major mechanisms of resistance at the molecular level makes it possible to diagnose the presence of modified acetylcholinesterase (MACE) or knockdown resistance (kdr).