Characterization of the key antigenic components and pre-clinical immune responses to a meningococcal disease vaccine based onNeisseria lactamicaouter membrane vesicles

Phase I Safety and Immunogenicity Study of a Candidate Meningococcal Disease Vaccine Based on Neisseria lactamica Outer Membrane Vesicles

“…N. lactamica does not possess a capsule or PorA, so any protection provided by carriage of this organism would not be serogroup or serosubtype specific. We have demonstrated that vaccines prepared from N. lactamica protect mice from lethal challenge in a mouse model of meningococcal septicemia (17,26) in the absence of an SBA response (11). This is in contrast to SBA responses observed in children following colonization with this organism (15).…”

“…Fourfold or greater rises in SBA were detected in 52% of children older than 4 years, while efficacy was shown to be greater that 70% in this age group (8,23). Also, protection in the absence of SBA has been demonstrated for the N. lactamica OMV vaccine (11,26) in an adult mouse disease model and in infant rats by using sera against a number of meningococcal antigens raised in laboratory animals (38,39) and in human recipients of polysaccharide vaccines (37). We have assessed the safety and immunogenicity of an N. lactamica OMV vaccine in adult volunteers.…”

“…The N. lactamica OMV vaccine was produced at the Health Protection Agency Centre for Emergency Preparedness and Response. N. lactamica strain Y92-1009 (sequence type 3493/clonal complex 613) was cultured as described previously (11). OMV bulk preparations in 0.2 M glycine, pH 8.0, with 3.0% sucrose were stored at Ϫ80°C before being thawed, pooled, and then filtered using two 0.2-m filters.…”

Carriage of Neisseria lactamica in 1- to 29-Year-Old People in Burkina Faso: Epidemiology and Molecular Characterization

“…Early studies have shown that N. lactamica carriage is frequent in age groups with low prevalence of N. meningitidis asymptomatic carriage and vice versa (15,32). It is believed that carriage of N. lactamica can protect against meningococcal infection by crossreactive immunity (11), and meningococcal vaccines based on N. lactamica have been considered (14,16).…”

Post-genomics ofNeisseria meningitidis: an update

“…An alternative approach to a vaccine for serogroup B meningococcal disease has been applied by Finney and colleagues in the development of an OMV vaccine based on the commensal N. lactamica, a close taxonomic relative of N. meningitidis [55]. Immunological and epidemiological evidence suggests that carriage of N. lactamica contributes to the age-related development of natural immunity against meningococcal disease, most probably due to the development of antibodies against many surface structures shared with N. meningitidis [56,57].…”