Development and characterisation of outer membrane vesicle vaccines against serogroup A Neisseria meningitidis

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

“…In the same blot, the band closest to the position of OpC in the meningococcal immunoprobed lane is actually migrating ahead of OpC. The major immunoreactive band at ~85 kDa was identified tentatively as Omp85, 25 but could equally well have been NMA1558 or NMB0280 or some minor protein not definitively identified in this study. The picture is further complicated by the presence of a protein identified as HpuB migrating at ~85 kDa in N. lactamica OMVs, as the hpuAB locus is absent from the sequenced serogroup B genome.…”

Functional and Specific Antibody Responses in Adult Volunteers in New Zealand Who Were Given One of Two Different Meningococcal Serogroup B Outer Membrane Vesicle Vaccines

“…NspA is a conserved surface-exposed meningococcal protein that gives rise to bactericidal and protective antibodies in mice (32) but not in humans (21 (40), so a species difference in the immune response to this antigen seems possible. Both vaccines induced increased IgG antibody binding on blots to the Omp85, PorA, FbpA, RmpM, OpcA, and LPS antigens in the homologous and heterologous OMVs.…”

“…Specific IgG antibodies to NspA protein were measured in microtiter plates (Maxisorp; Nunc, Roskilde, Denmark) coated with OMVs prepared from Escherichia coli cells that did or did not express recombinant NspA (rNspA), as described previously (38,40). The difference in IgG antibody binding between rNspA-positive and rNspA-negative OMVs was taken to represent the binding of NspA-specific antibodies.…”

Persistence of the immune response after MenACWY-CRM vaccination and response to a booster dose, in adolescents, children and infants

“…47,48 Another recent study on MenAfriVac Ò use in the African population has indicated a 94% reduction in the crude incidence rate of meningococcal serogroup A disease with a 98% decrease in the prevalence of MenA carriage. 49 Interestingly, antibodies against serogroup A at 1 y after vaccination with MenAfriVac Ò declined sharply when assessed using hSBA but remained high when assessed using rSBA, 50 indicating that hSBA antibody levels in these vaccinated populations may not correlate directly with the observed efficacy of the vaccine and protection against invasive disease. Based on these observations, one might speculate that hSBA may not be the ideal assay for assessing persistence against serogroup A, and that hSBA titers may underestimate actual protection against disease.…”