Mutant Native Outer Membrane Vesicles Combined with a Serogroup A Polysaccharide Conjugate Vaccine for Prevention of Meningococcal Epidemics in Africa

Pajón, Rolando; Fergus, Andrew M.; Granoff, Dan M.

doi:10.1371/journal.pone.0066536

Cited by 17 publications

(30 citation statements)

References 93 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, in the present study we transformed E. coli strain BL21(DE3) competent cells (Life Technologies) with a pUC19-based plasmid construct (pEHNspA; see Fig. S1 in the supplemental material) containing an NspA gene cloned from serogroup W strain Sudan 1/06 (Su 1/06) (16), an upstream EH promoter described previously (16), and an ampicillin resistance marker. The NspA gene, which was identical to that from group B strain LNP21362 described previously (17), including its natural signal peptide-coding segment, was cloned for surface expression in E. coli.…”

Section: Methodsmentioning

confidence: 99%

“…To determine whether the human FH transgenic mice had impaired serum antibody responses to antigens that did not bind human FH, we prepared a control meningococcal native outer membrane vesicle (NOMV) vaccine, which was derived from a previously described mutant of N. meningitidis strain Su 1/06 (W:P1.5,2: sequence type 11 [ST-11; clonal complex 11 {CC11}]) (16). The mutant vaccine strain had a genetically attenuated endotoxin (lpxL1 knockout), its capsular expression was deleted, and it overexpressed mutant subfamily B FHbp (peptide identification number [ID] 9) containing one amino acid substitution (R41S) that decreased the binding of FH Ͼ50-fold compared to the level of FH binding by the respective wild-type FHbp (11).…”

Section: Methodsmentioning

confidence: 99%

“…The mutant vaccine strain had a genetically attenuated endotoxin (lpxL1 knockout), its capsular expression was deleted, and it overexpressed mutant subfamily B FHbp (peptide identification number [ID] 9) containing one amino acid substitution (R41S) that decreased the binding of FH Ͼ50-fold compared to the level of FH binding by the respective wild-type FHbp (11). By Western blotting, expression of the mutant subfamily B FHbp in the vaccine strain was 10-fold higher than that in the parent strain (16). For the present study, we inserted an additional copy of a mutant subfamily A FHbp (ID 22) with one amino acid substitution (D211A) that also decreased the binding of FH Ͼ50-fold (19).…”

Section: Methodsmentioning

confidence: 99%

“…The major outer membrane proteins were analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) and Western blotting as described previously (15,16). In the Western blotting assay, NspA was detected with a previously described anti-NspA monoclonal antibody (MAb), AL12 (21).…”

Section: Methodsmentioning

confidence: 99%

“…This strain naturally expresses high levels of NspA, is susceptible to anti-NspA bactericidal activity (15), and has a subfamily B FHbp (ID 14) that matches the subfamily of the FHbp (ID 9) overexpressed in the NOMV vaccine. To evaluate anti-PorA serum bactericidal antibody responses to the control meningococcal NOMV vaccine, we used a group W strain, Burkina Faso 2/03 (BuFa 2/03) (W:P1.5,2; ST-11 [CC11]) (16). This strain has the PorA VR sequence type P1.5,2, which matches that of the PorA of the meningococcal strain used to prepare the NOMV vaccine, and expresses a subfamily A FHbp (ID 23) which is mismatched to the overexpressed subfamily B FHbp in the NOMV vaccine.…”

Section: Methodsmentioning

confidence: 99%

See 4 more Smart Citations

Impaired Immunogenicity of Meningococcal Neisserial Surface Protein A in Human Complement Factor H Transgenic Mice

2016

Self Cite

View full text Add to dashboard Cite

Neisserial surface protein A (NspA) is a highly conserved outer membrane protein previously investigated as a meningococcal vaccine candidate. Despite eliciting serum bactericidal activity in mice, a recombinant NspA vaccine failed to elicit serum bactericidal antibodies in a phase 1 clinical trial in humans. The discordant results may be explained by the recent discovery that NspA is a human-specific ligand of the complement inhibitor factor H (FH). Therefore, in humans but not mice, NspA would be expected to form a complex with FH, which could impair human anti-NspA protective antibody responses. To investigate this question, we immunized human FH transgenic BALB/c mice with three doses of recombinant NspA expressed in Escherichia coli microvesicles, with each dose being separated by 3 weeks. Three of 12 (25%) transgenic mice and 13 of 14 wild-type mice responded with bactericidal titers of >1:10 in postimmunization sera (P ‫؍‬ 0.0008, Fisher's exact test). In contrast, human FH transgenic and wild-type mice immunized with a control meningococcal native outer membrane vesicle vaccine had similar serum bactericidal antibody responses directed at PorA, which is not known to bind human FH, and a mutant factor H binding protein ( T he 1990s witnessed the discovery of two promising recombinant protein meningococcal vaccine candidates capable of eliciting broad serum bactericidal antibody responses in mice: neisserial surface protein A (NspA) (1-3) and transferrin-binding protein (TbpB) (4-6). However, in phase 1 clinical trials, both recombinant protein vaccines failed to elicit serum bactericidal antibody responses in humans (7,8). NspA was subsequently shown to bind specifically to human complement factor H (FH) (9), and transferrin-binding protein was known to bind specifically to human and not mouse transferrin (10). The impaired serum bactericidal antibody responses to these vaccines in humans may have resulted in part from binding of the host proteins to the vaccine antigens. For example, human FH transgenic mice immunized with meningococcal factor H binding protein (FHbp) vaccines that bound human FH had lower serum anti-FHbp bactericidal antibody responses than wild-type mice whose mouse FH did not bind to FHbp (11,12). Rhesus macaques with FH that bound with a high avidity to FHbp also had lower serum antiFHbp bactericidal antibody responses than macaques with FH containing a polymorphism associated with low-avidity binding to FHbp (13). Pigs immunized with a mutant Haemophilus parasuis TbpB vaccine with decreased binding to porcine transferrin elicited higher T-and B-cell responses than pigs immunized with a native TbpB that bound porcine transferrin (12).NspA is highly conserved in Neisseria meningitidis (1) and, therefore, would be of interest for use as a component of a serogroup B vaccine if the antigen were capable of eliciting protective antibodies in humans. In the present study, we immunized wildtype and human FH transgenic BALB/c mice with a prototype recombinant NspA vaccine expressed in Esche...

show abstract

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 3 more Smart Citations

Impaired Immunogenicity of Meningococcal Neisserial Surface Protein A in Human Complement Factor H Transgenic Mice

2016

Self Cite

View full text Add to dashboard Cite

show abstract

Outer membrane vesicles as a platform for the discovery of antibodies to bacterial pathogens

Lei,

Azmat,

Henry

et al. 2024

Appl Microbiol Biotechnol

View full text Add to dashboard Cite

Bacterial outer membrane vesicles (OMVs) are nanosized spheroidal particles shed by gram-negative bacteria that contain biomolecules derived from the periplasmic space, the bacterial outer membrane, and possibly other compartments. OMVs can be purified from bacterial culture supernatants, and by genetically manipulating the bacterial cells that produce them, they can be engineered to harbor cargoes and/or display molecules of interest on their surfaces including antigens that are immunogenic in mammals. Since OMV bilayer-embedded components presumably maintain their native structures, OMVs may represent highly useful tools for generating antibodies to bacterial outer membrane targets. OMVs have historically been utilized as vaccines or vaccine constituents. Antibodies that target bacterial surfaces are increasingly being explored as antimicrobial agents either in unmodified form or as targeting moieties for bactericidal compounds. Here, we review the properties of OMVs, their use as immunogens, and their ability to elicit antibody responses against bacterial antigens. We highlight antigens from bacterial pathogens that have been successfully targeted using antibodies derived from OMV-based immunization and describe opportunities and limitations for OMVs as a platform for antimicrobial antibody development. Key points • Outer membrane vesicles (OMVs) of gram-negative bacteria bear cell-surface molecules • OMV immunization allows rapid antibody (Ab) isolation to bacterial membrane targets • Review and analysis of OMV-based immunogens for antimicrobial Ab development

show abstract

Outer membrane vesicle vaccines

Micoli

MacLennan

2020

Seminars in Immunology

137

124

View full text Add to dashboard Cite

Mutant Native Outer Membrane Vesicles Combined with a Serogroup A Polysaccharide Conjugate Vaccine for Prevention of Meningococcal Epidemics in Africa

Cited by 17 publications

References 93 publications

Impaired Immunogenicity of Meningococcal Neisserial Surface Protein A in Human Complement Factor H Transgenic Mice

Impaired Immunogenicity of Meningococcal Neisserial Surface Protein A in Human Complement Factor H Transgenic Mice

Outer membrane vesicles as a platform for the discovery of antibodies to bacterial pathogens

Outer membrane vesicle vaccines

Contact Info

Product

Resources

About