title: Process development and immunogenicity studies on a serogroup 'X' Meningococcal polysaccharide conjugate vaccine.
abstract: Meningococcal group X (MenX) is responsible for recent outbreaks of meningitis reported in sub-Saharan region of Africa. Although protective vaccines are available for meningitis, they are not effective against MenX. An efficacious, monovalent conjugate vaccine was designed against MenX and a fed-batch fermentation process was developed. The MenX polysaccharide (PS) was purified and yield estimated to be 15-fold higher than the reported elsewhere. Structure of MenX polysaccharide was confirmed by (1)H, (13)C NMR spectroscopy analysis. Molecular weight of PS was found to be 310 kDa using HPLC-SEC coupled to refractive index (RI) detector. The MenX-Tetanus toxoid (TT) monovalent conjugate proved to be highly immunogenic in mice, and the bactericidal titers of MenX-TT conjugate were 10-fold higher than native PS. Increasing the dose of MenX-TT conjugate from 0.5 μg to 1.0 μg induced an 8-fold higher antibody titer as well as serum bactericidal titer. The current work suggests that the MenX-TT conjugate is a candidate vaccine against meningitis caused by Meningococcal group X strains.
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India. Electronic address: srinivaschreddy@gmail.com.
authors.forename: Srinivas Reddy
authors.initials: SR
authors.lastname: Chilukuri
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India.
authors.forename: Peddi
authors.initials: P
authors.lastname: Reddy
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Avalaskar
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India.
authors.forename: Asha
authors.initials: A
authors.lastname: Mallya
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India.
authors.forename: Sambhaji
authors.initials: S
authors.lastname: Pisal
authors.affiliation: Research and Development Department, Serum Institute of India Ltd, Serum Biopharma Park, 212/2, Hadapsar, Pune 411028, Maharashtra, India.
authors.forename: Rajeev M
authors.initials: RM
authors.lastname: Dhere
mesh_terms: D017954:Africa South of the Sahara; D000818:Animals; D066241:Carbon-13 Magnetic Resonance Spectroscopy; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D022401:Meningococcal Vaccines / Q000276:immunology*; D051379:Mice
chemical_list: D022401:Meningococcal Vaccines
keywords: Capsular polysaccharide; High performance liquid chromatography – size exclusion chromatography (HPLC-SEC); Lipopolysaccharide; Meningococcal group X; Serum bactericidal assay titer; Tetanus toxoid