Meningococcal Detoxified Outer Membrane Vesicle Vaccines Enhance Gonococcal Clearance in a Murine Infection Model

Abstract Background Despite decades of research efforts, development of a gonorrhea vaccine has remained elusive. Epidemiological studies suggest that detoxified outer membrane vesicle (dOMV) vaccines from Neisseria meningitidis (Nm) may protect against infection with Neisseria gonorrhoeae (Ng). We recently reported that Nm dOMVs lacking the major outer membrane proteins (OMPs) PorA, PorB, and RmpM induced greater antibody cross-reactivity against heterologous Nm strains than wild-type (WT) dOMVs and may represent an improved vaccine against gonorrhea. Methods We prepared dOMV vaccines from meningococcal strains that were sufficient or deleted for PorA, PorB, and RmpM. Vaccines were tested in a murine genital tract infection model and antisera were used to identify vaccine targets. Results Immunization with Nm dOMVs significantly and reproducibly enhanced gonococcal clearance for mice immunized with OMP-deficient dOMVs; significant clearance for WT dOMV-immunized mice was observed in one of two experiments. Clearance was associated with serum and vaginal anti-Nm dOMV IgG antibodies that cross-reacted with Ng. Serum IgG was used to identify putative Ng vaccine targets, including PilQ, MtrE, NlpD, and GuaB. Conclusions Meningococcal dOMVs elicited a protective effect against experimental gonococcal infection. Recognition and identification of Ng vaccine targets by Nm dOMV-induced antibodies supports the development of a cross-protective Neisseria vaccine.

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The serogroup B meningococcal outer membrane vesicle-based vaccine 4CMenB induces cross-species protection against Neisseria gonorrhoeae

10.1101/2020.05.13.094177 ◽

2020 ◽

Author(s):

Isabelle Leduc ◽

Kristie L. Connolly ◽

Afrin Begum ◽

Knashka Underwood ◽

Nazia Rahman ◽

...

Keyword(s):

Mouse Model ◽

Neisseria Gonorrhoeae ◽

Neisseria Meningitidis ◽

Outer Membrane ◽

Membrane Vesicle ◽

Outer Membrane Proteins ◽

Infection Model ◽

Outer Membrane Vesicle ◽

Epidemiological Evidence ◽

Species Protection

AbstractThere is a pressing need for a gonorrhea vaccine due to the high disease burden associated with gonococcal infections globally and the rapid evolution of antibiotic resistance in Neisseria gonorrhoeae (Ng). Current gonorrhea vaccine research is in the stages of antigen discovery and the identification of protective immune responses, and no vaccine has been tested in clinical trials in over 30 years. Recently, however, it was reported in a retrospective case-control study that vaccination of humans with a serogroup B Neisseria meningitidis (Nm) outer membrane vesicle (OMV) vaccine (MeNZB) was associated with reduced rates of gonorrhea. Here we directly tested the hypothesis that Nm OMVs induce cross-protection against gonorrhea in a well-characterized female mouse model of Ng genital tract infection. We found that immunization with the licensed Nm OMV-based vaccine 4CMenB (Bexsero®) significantly accelerated clearance and reduced the Ng bacterial burden compared to administration of alum or PBS. High titers of serum IgG1 and IgG2a and vaginal IgG1 that cross-reacted with Ng OMVs were induced by vaccination via either the subcutaneous or intraperitoneal routes, and a 4-fold increase in the serum bactericidal50 titers was detected against the challenge strain. Antibodies from vaccinated mice recognized several surface proteins in a diverse collection of Ng strains, including PilQ, BamA, MtrE, PorB, and Opa, and 4CMenB-induced antibodies bound PilQ and MtrE in native form on the surface of viable bacteria. In contrast, the antibodies were only cross-reactive against lipooligosaccharide species from a few Ng strains. Our findings directly support epidemiological evidence that Nm OMVs confer cross-species protection against Ng and implicate several Ng surface antigens as potentially protective targets. This work also validates the murine infection model as a relevant experimental system for investigating mechanisms of vaccine-mediated protection against gonorrhea.Author summaryOver 78 million Neisseria gonorrhoeae (Ng) infections occur globally each year and control of gonorrhea through vaccination is challenged by a lack of strong evidence that immunity to gonorrhea is possible. This contention was recently challenged by epidemiological evidence suggesting that an outer membrane vesicle (OMV) vaccine from the related species Neisseria meningitidis (Nm) protected humans against gonorrhea. Here we provide experimental evidence in support of this hypothesis by demonstrating that a licensed, modified version of this Nm OMV-based vaccine accelerates clearance of Ng in a mouse infection model. These results confirm the possibility cross-species protection and are important in that they support the biological feasibility of vaccine-induced immunity against gonorrhea. We also showed that several Ng outer membrane proteins are recognized by antisera from vaccinated mice that may be protective targets of the vaccine. Additionally, our demonstration that a vaccine that may reduce the risk of gonorrhea in humans protects mice against Ng, a highly host-restricted pathogen, validates the mouse model as a potentially useful tool for examining mechanisms of protection, which could be exploited in the development of other candidate gonorrhea vaccines.

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The Role of Virulence Proteins in Protection Conferred by Bordetella pertussis Outer Membrane Vesicle Vaccines

Vaccines ◽

10.3390/vaccines8030429 ◽

2020 ◽

Vol 8 (3) ◽

pp. 429

Author(s):

René H. M. Raeven ◽

Naomi van Vlies ◽

Merijn L. M. Salverda ◽

Larissa van der Maas ◽

Joost P. Uittenbogaard ◽

...

Keyword(s):

Outer Membrane ◽

Bordetella Pertussis ◽

Protective Immunity ◽

Membrane Vesicle ◽

Outer Membrane Proteins ◽

Outer Membrane Vesicle ◽

Protective Capacity ◽

T Helper 1 ◽

Virulence Proteins ◽

Humoral Responses

The limited protective immunity induced by acellular pertussis vaccines demands development of novel vaccines that induce broader and longer-lived immunity. In this study, we investigated the protective capacity of outer membrane vesicle pertussis vaccines (omvPV) with different antigenic composition in mice to gain insight into which antigens contribute to protection. We showed that total depletion of virulence factors (bvg(-) mode) in omvPV led to diminished protection despite the presence of high antibody levels. Antibody profiling revealed overlap in humoral responses induced by vaccines in bvg(-) and bvg(+) mode, but the potentially protective responses in the bvg(+) vaccine were mainly directed against virulence-associated outer membrane proteins (virOMPs) such as BrkA and Vag8. However, deletion of either BrkA or Vag8 in our outer membrane vesicle vaccines did not affect the level of protection. In addition, the vaccine-induced immunity profile, which encompasses broad antibody and mixed T-helper 1, 2 and 17 responses, was not changed. We conclude that the presence of multiple virOMPs in omvPV is crucial for protection against Bordetella pertussis. This protective immunity does not depend on individual proteins, as their absence or low abundance can be compensated for by other virOMPs.

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Contribution of factor H-Binding protein sequence to the cross-reactivity of meningococcal native outer membrane vesicle vaccines with over-expressed fHbp variant group 1

PLoS ONE ◽

10.1371/journal.pone.0181508 ◽

2017 ◽

Vol 12 (7) ◽

pp. e0181508 ◽

Cited By ~ 2

Author(s):

Arianna Marini ◽

Omar Rossi ◽

Maria Grazia Aruta ◽

Francesca Micoli ◽

Simona Rondini ◽

...

Keyword(s):

Outer Membrane ◽

Protein Sequence ◽

Binding Protein ◽

Membrane Vesicle ◽

Cross Reactivity ◽

Factor H ◽

Outer Membrane Vesicle ◽

The Cross ◽

Group 1

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Genetic Similarity of Gonococcal Homologs to Meningococcal Outer Membrane Proteins of Serogroup B Vaccine

mBio ◽

10.1128/mbio.01668-19 ◽

2019 ◽

Vol 10 (5) ◽

Cited By ~ 2

Author(s):

Henju Marjuki ◽

Nadav Topaz ◽

Sandeep J. Joseph ◽

Kim M. Gernert ◽

Ellen N. Kersh ◽

...

Keyword(s):

Membrane Proteins ◽

Outer Membrane ◽

Vaccine Development ◽

Membrane Vesicle ◽

Outer Membrane Proteins ◽

The United States ◽

Cross Protection ◽

Outer Membrane Vesicle ◽

Content Type ◽

Sequence Identity

ABSTRACT The human pathogens Neisseria gonorrhoeae and Neisseria meningitidis share high genome identity. Retrospective analysis of surveillance data from New Zealand indicates the potential cross-protective effect of outer membrane vesicle (OMV) meningococcal serogroup B vaccine (MeNZB) against N. gonorrhoeae. A licensed OMV-based MenB vaccine, MenB-4C, consists of a recombinant FHbp, NhbA, NadA, and the MeNZB OMV. Previous work has identified several abundantly expressed outer membrane proteins (OMPs) as major components of the MenB-4C OMV with high sequence similarity between N. gonorrhoeae and N. meningitidis, suggesting a mechanism for cross-protection. To build off these findings, we performed comparative genomic analysis on 970 recent N. gonorrhoeae isolates collected through a U.S surveillance system against N. meningitidis serogroup B (NmB) reference sequences. We identified 1,525 proteins that were common to both Neisseria species, of which 57 proteins were predicted to be OMPs using in silico methods. Among the MenB-4C antigens, NhbA showed moderate sequence identity (73%) to the respective gonococcal homolog, was highly conserved within N. gonorrhoeae, and was predicted to be surface expressed. In contrast, the gonococcal FHbp was predicted not to be surface expressed, while NadA was absent in all N. gonorrhoeae isolates. Our work confirmed recent observations (E. A. Semchenko, A. Tan, R. Borrow, and K. L. Seib, Clin Infect Dis, 2018, https://doi.org/10.1093/cid/ciy1061) and describes homologous OMPs from a large panel of epidemiologically relevant N. gonorrhoeae strains in the United States against NmB reference strains. Based on our results, we report a set of OMPs that may contribute to the previously observed cross-protection and provide potential antigen targets to guide the next steps in gonorrhea vaccine development. IMPORTANCE Gonorrhea, a sexually transmitted disease, causes substantial global morbidity and economic burden. New prevention and control measures for this disease are urgently needed, as strains resistant to almost all classes of antibiotics available for treatment have emerged. Previous reports demonstrate that cross-protection from gonococcal infections may be conferred by meningococcal serogroup B (MenB) outer membrane vesicle (OMV)-based vaccines. Among 1,525 common proteins shared across the genomes of both N. gonorrhoeae and N. meningitidis, 57 proteins were predicted to be surface expressed (outer membrane proteins [OMPs]) and thus preferred targets for vaccine development. The majority of these OMPs showed high sequence identity between the 2 bacterial species. Our results provide valuable insight into the meningococcal antigens present in the current OMV-containing MenB-4C vaccine that may contribute to cross-protection against gonorrhea and may inform next steps in gonorrhea vaccine development.

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The serogroup B meningococcal outer membrane vesicle-based vaccine 4CMenB induces cross-species protection against Neisseria gonorrhoeae

PLoS Pathogens ◽

10.1371/journal.ppat.1008602 ◽

2020 ◽

Vol 16 (12) ◽

pp. e1008602

Author(s):

Isabelle Leduc ◽

Kristie L. Connolly ◽

Afrin Begum ◽

Knashka Underwood ◽

Stephen Darnell ◽

...

Keyword(s):

Neisseria Gonorrhoeae ◽

Outer Membrane ◽

Vaccine Development ◽

Membrane Vesicle ◽

Surface Proteins ◽

Mouse Serum ◽

Infection Model ◽

Outer Membrane Vesicle ◽

Species Protection ◽

Significant Difference

There is a pressing need for a gonorrhea vaccine due to the high disease burden associated with gonococcal infections globally and the rapid evolution of antibiotic resistance in Neisseria gonorrhoeae (Ng). Current gonorrhea vaccine research is in the stages of antigen discovery and the identification of protective immune responses, and no vaccine has been tested in clinical trials in over 30 years. Recently, however, it was reported in a retrospective case-control study that vaccination of humans with a serogroup B Neisseria meningitidis (Nm) outer membrane vesicle (OMV) vaccine (MeNZB) was associated with reduced rates of gonorrhea. Here we directly tested the hypothesis that Nm OMVs induce cross-protection against gonorrhea in a well-characterized female mouse model of Ng genital tract infection. We found that immunization with the licensed Nm OMV-based vaccine 4CMenB (Bexsero) significantly accelerated clearance and reduced the Ng bacterial burden compared to administration of alum or PBS. Serum IgG and vaginal IgA and IgG that cross-reacted with Ng OMVs were induced by 4CMenB vaccination by either the subcutaneous or intraperitoneal routes. Antibodies from vaccinated mice recognized several Ng surface proteins, including PilQ, BamA, MtrE, NHBA (known to be recognized by humans), PorB, and Opa. Immune sera from both mice and humans recognized Ng PilQ and several proteins of similar apparent molecular weight, but MtrE was only recognized by mouse serum. Pooled sera from 4CMenB-immunized mice showed a 4-fold increase in serum bactericidal50 titers against the challenge strain; in contrast, no significant difference in bactericidal activity was detected when sera from 4CMenB-immunized and unimmunized subjects were compared. Our findings directly support epidemiological evidence that Nm OMVs confer cross-species protection against gonorrhea, and implicate several Ng surface antigens as potentially protective targets. Additionally, this study further defines the usefulness of murine infection model as a relevant experimental system for gonorrhea vaccine development.

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Immunogenicity studies with a genetically engineered hexavalent PorA and a wild-type meningococcal group B outer membrane vesicle vaccine in infant cynomolgus monkeys

Vaccine ◽

10.1016/s0264-410x(99)00402-8 ◽

2000 ◽

Vol 18 (14) ◽

pp. 1334-1343 ◽

Cited By ~ 16

Author(s):

Eileene Rouppe van der Voort ◽

Margje Schuller ◽

Johan Holst ◽

Petra de Vries ◽

Peter van der Ley ◽

...

Keyword(s):

Outer Membrane ◽

Membrane Vesicle ◽

Genetically Engineered ◽

Outer Membrane Vesicle ◽

Wild Type ◽

Cynomolgus Monkeys ◽

Meningococcal Group ◽

Group B

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Regulation of outer-membrane proteins (OMPs) A and F, during hlyF-induced outer-membrane vesicle (OMV) biosynthesis

Heliyon ◽

10.1016/j.heliyon.2019.e02014 ◽

2019 ◽

Vol 5 (7) ◽

pp. e02014 ◽

Cited By ~ 2

Author(s):

Wouter André van der Westhuizen ◽

Chrispian William Theron ◽

Charlotte Enastacia Boucher ◽

Robert Richard Bragg

Keyword(s):

Membrane Proteins ◽

Outer Membrane ◽

Membrane Vesicle ◽

Outer Membrane Proteins ◽

Outer Membrane Vesicle

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Cross-Reactivity of Antibodies against PorA after Vaccination with a Meningococcal B Outer Membrane Vesicle Vaccine

Infection and Immunity ◽

10.1128/iai.71.4.1650-1655.2003 ◽

2003 ◽

Vol 71 (4) ◽

pp. 1650-1655 ◽

Cited By ~ 32

Author(s):

C. L. Vermont ◽

H. H. van Dijken ◽

A. J. Kuipers ◽

C. J. P. van Limpt ◽

W. C. M. Keijzers ◽

...

Keyword(s):

Outer Membrane ◽

Vaccine Strain ◽

Vaccine Coverage ◽

Membrane Vesicle ◽

Geometric Mean ◽

Cross Reactivity ◽

Outer Membrane Vesicle ◽

Specific Antibodies ◽

Fourfold Increase ◽

The Cross

ABSTRACT The cross-reactivity of PorA-specific antibodies induced by a monovalent P1.7-2,4 (MonoMen) and/or a hexavalent (HexaMen) meningococcal B outer membrane vesicle vaccine (OMV) in toddlers and school children was studied by serum bactericidal assays (SBA). First, isogenic vaccine strains and PorA-identical patient isolates were compared as a target in SBA, to ensure that the vaccine strains are representative for patient isolates. Geometric mean titers (GMTs) in SBA against patient isolates with subtypes P1.5-2,10 and P1.5-1,2-2 after vaccination with HexaMen were generally lower than those against vaccine strains with the same subtype, although the percentage of vaccine responders (≥4-fold increase in SBA after vaccination) was not affected. Using various P1.7-2,4 patient isolates, GMTs as well as the number of vaccine responders were higher than for the P1.7-2,4 vaccine strain, indicating that the use of the P1.7-2,4 vaccine strain may have underestimated the immunogenicity of this subtype in HexaMen. Secondly, the cross-reactivity of antibodies induced by MonoMen and HexaMen was studied using several patient isolates that differed from the vaccine subtypes by having minor antigenic variants of one variable region (VR), by having a completely different VR or by having a different combination of VRs. MonoMen induced P1.4-specific antibodies that were cross-reactive with P1.4 variants P1.4-1 and P1.4-3. HexaMen induced a broader cross-reactive antibody response against various patient isolates with one VR identical to a vaccine subtype or a combination of VRs included in HexaMen. Cross-reactivity, measured by a fourfold increase in SBA after vaccination, against these strains ranged from 23 to 92% depending on the subtype of the tested strain and was directed against both VR1 and VR2. The extended cross-reactivity of vaccinee sera induced by HexaMen against antigenic variants has important favorable implications for meningococcal B OMV vaccine coverage.

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