Frontiers in immunology
Neisseria meningitidis serogroup X polysaccharide as a qualified antigen for multivalent meningococcal conjugate vaccines
By Fu D, Li K, Shi X and 11 others.
Abstract
Background
Meningococcal meningitis remains a severe global health threat to infants, with multivalent vaccination serving as the most effective preventive measure. In 2021, World Health Organization (WHO) released Defeating Meningitis by 2030: A Global Roadmap, highlighting an urgent demand for conjugate vaccines covering an expanded spectrum of meningococcal serogroups. Accordingly, the development of affordable and globally accessible diagnostic and preventive strategies, including protection against Neisseria meningitidis serogroup X (MenX), has become a key public health priority.
Methods
A comprehensive multi-analytical strategy was implemented, incorporating whole-genome sequencing (WGS), electron microscopy, nuclear magnetic resonance (NMR), Fourier-transform infrared spectroscopy (FTIR), Congo red staining assay, size-exclusion chromatography coupled with multi-angle laser light scattering (SEC-MALLS), thermogravimetric analysis/derivative thermogravimetry (TGA/DTG), differential scanning calorimetry (DSC), immunodiffusion assays, enzyme-linked immunosorbent assay (ELISA), and serum bactericidal assay, to systematically evaluate the genetic stability of the MenX production strain, alongside the molecular structure, physicochemical properties, antigenicity, and immunogenicity of MenX polysaccharide (MenX PS).