Synthetic Fragments of Vibrio cholerae O1 Inaba O-Specific Polysaccharide Bound to a Protein Carrier Are Immunogenic in Mice but Do Not Induce Protective Antibodies

ABSTRACT Development of Vibrio cholerae lipopolysaccharide (LPS) as a cholera vaccine immunogen is justified by the correlation of vibriocidal anti-LPS response with immunity. Two V. cholerae O1 LPS serotypes, Inaba and Ogawa, are associated with endemic and pandemic cholera. Both serotypes induce protective antibody following infection or vaccination. Structurally, the LPSs that define the serotypes are identical except for the terminal perosamine moiety, which has a methoxyl group at position 2 in Ogawa but a hydroxyl group in Inaba. The terminal sugar of the Ogawa LPS is a protective B-cell epitope. We chemically synthesized the terminal hexasaccharides of V. cholerae serotype Ogawa, which comprises in part the O-specific polysaccharide component of the native LPS, and coupled the oligosaccharide at different molar ratios to bovine serum albumin (BSA). Our initial studies with Ogawa immunogens showed that the conjugates induced protective antibody. We hypothesized that antibodies specific for the terminal sugar of Inaba LPS would also be protective. Neoglycoconjugates were prepared from synthetic Inaba oligosaccharides (disaccharide, tetrasaccharide, and hexasaccharide) and BSA at different levels of substitution. BALB/c mice responded to the Inaba carbohydrate (CHO)-BSA conjugates with levels of serum antibodies of comparable magnitude to those of mice immunized with Ogawa CHO-BSA conjugates, but the Inaba-specific antibodies (immunoglobulin M [IgM] and IgG1) were neither vibriocidal nor protective in the infant mouse cholera model. We hypothesize that the anti-Inaba antibodies induced by the Inaba CHO-BSA conjugates have enough affinity to be screened via enzyme-linked immunosorbent assay but not enough to be protective in vivo.

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Preparation, Immunogenicity, and Protective Efficacy, in a Murine Model, of a Conjugate Vaccine Composed of the Polysaccharide Moiety of the Lipopolysaccharide of Vibrio cholerae O139 Bound to Tetanus Toxoid

Infection and Immunity ◽

10.1128/iai.69.5.3488-3493.2001 ◽

2001 ◽

Vol 69 (5) ◽

pp. 3488-3493 ◽

Cited By ~ 51

Author(s):

Alain Boutonnier ◽

Sylvain Villeneuve ◽

Farida Nato ◽

Bruno Dassy ◽

Jean-Michel Fournier

Keyword(s):

Vibrio Cholerae ◽

Tetanus Toxoid ◽

Capsular Polysaccharide ◽

Protective Efficacy ◽

Immunoglobulin M ◽

Enzyme Linked Immunosorbent Assay ◽

Igg Antibodies ◽

Vibrio Cholerae O139 ◽

Specific Polysaccharide ◽

Antibody Levels

ABSTRACT The epidemic and pandemic potential of Vibrio choleraeO139 is such that a vaccine against this newly emerged serogroup ofV. cholerae is required. A conjugate made of the polysaccharide moiety (O-specific polysaccharide plus core) of the lipopolysaccharide (LPS) of V. cholerae O139 (pmLPS) was prepared by derivatization of the pmLPS with adipic acid dihydrazide and coupling to tetanus toxoid (TT) by carbodiimide-mediated condensation. The immunologic properties of the conjugate were tested using BALB/c mice injected subcutaneously three times at 2 weeks interval and then a fourth time 4 weeks later. Mice were bled 7 days after each injection and then once each month for the following 6 months. LPS and TT antibody levels were determined by enzyme-linked immunosorbent assay using immunoplates coated with either O139 LPS or TT. Both pmLPS and pmLPS-TT conjugate elicited low levels of immunoglobulin M (IgM), peaking 5 weeks after the first immunization. The conjugate elicited high levels of IgG antibodies, peaking 3 months after the first immunization and declining slowly during the following 5 months. TT alone, or as a component of conjugate, induced mostly IgG antibodies. Antibodies elicited by the conjugate recognized both capsular polysaccharide and LPS from V. cholerae O139 and were vibriocidal. They were also protective in the neonatal mouse model of cholera infection. The conjugation of the O139 pmLPS, therefore, enhanced its immunogenicity and conferred T-dependent properties to this polysaccharide.

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A Novel Mouse Monoclonal Antibody C42 against C-Terminal Peptide of Alpha-1-Antitrypsin

International Journal of Molecular Sciences ◽

10.3390/ijms22042141 ◽

2021 ◽

Vol 22 (4) ◽

pp. 2141

Author(s):

Srinu Tumpara ◽

Elena Korenbaum ◽

Mark Kühnel ◽

Danny Jonigk ◽

Beata Olejnicka ◽

...

Keyword(s):

Monoclonal Antibody ◽

Flow Cytometry ◽

Western Blotting ◽

Complex Mixture ◽

Immunoglobulin M ◽

Confocal Laser ◽

Enzyme Linked Immunosorbent Assay ◽

Dot Blot

The C-terminal-fragments of alpha1-antitrypsin (AAT) have been identified and their diverse biological roles have been reported in vitro and in vivo. These findings prompted us to develop a monoclonal antibody that specifically recognizes C-36 peptide (corresponding to residues 359–394) resulting from the protease-associated cleavage of AAT. The C-36-targeting mouse monoclonal Immunoglobulin M (IgM) antibody (containing κ light chains, clone C42) was generated and enzyme-linked immunosorbent assay (ELISA)-tested by Davids Biotechnologie GmbH, Germany. Here, we addressed the effectiveness of the novel C42 antibody in different immunoassay formats, such as dot- and Western blotting, confocal laser microscopy, and flow cytometry. According to the dot-blot results, our novel C42 antibody detects the C-36 peptide at a range of 0.1–0.05 µg and shows no cross-reactivity with native, polymerized, or oxidized forms of full-length AAT, the AAT-elastase complex mixture, as well as with shorter C-terminal fragments of AAT. However, the C42 antibody does not detect denatured peptide in SDS-PAGE/Western blotting assays. On the other hand, our C42 antibody, unconjugated as well as conjugated to DyLight488 fluorophore, when applied for immunofluorescence microscopy and flow cytometry assays, specifically detected the C-36 peptide in human blood cells. Altogether, we demonstrate that our novel C42 antibody successfully recognizes the C-36 peptide of AAT in a number of immunoassays and has potential to become an important tool in AAT-related studies.

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In Vitro and In Vivo Neutralization of the Relapsing Fever Agent Borrelia hermsii with Serotype-Specific Immunoglobulin M Antibodies

Infection and Immunity ◽

10.1128/iai.69.2.1009-1015.2001 ◽

2001 ◽

Vol 69 (2) ◽

pp. 1009-1015 ◽

Cited By ~ 48

Author(s):

Alan G. Barbour ◽

Virgilio Bundoc

Keyword(s):

Monoclonal Antibodies ◽

Antibody Response ◽

Immunoglobulin M ◽

Enzyme Linked Immunosorbent Assay ◽

Relapsing Fever ◽

Borrelia Hermsii ◽

Intact Cells ◽

Whole Cells

ABSTRACT The antigenic variation of the relapsing fever agent Borrelia hermsii is associated with changes in the expression of the Vlp and Vsp outer membrane lipoproteins. To investigate whether these serotype-defining proteins are the target of a neutralizing and protective antibody response, monoclonal antibodies were produced from spleens of infected mice just after clearance of serotype 7 cells from the blood. Two immunoglobulin M monoclonal antibodies, H7-7 and H7-12, were studied in detail. Both antibodies specifically agglutinated serotype 7 cells and inhibited their growth in vitro. Administered to mice before or after infection, both antibodies provided protection against infection or substantially reduced the number of spirochetes in the blood of mice after infection. Whereas antibody H7-12 bound to Vlp7 in Western blotting, enzyme-linked immunosorbent assay, and immunoprecipitation assays, as well as to whole cells in other immunoassays, antibody H7-7 only bound to wet, intact cells of serotype 7. Antibody H7-7 selected against cells expressing Vlp7 in vitro and in vivo, an indication that Vlp7 was a conformation-sensitive antigen for the antibody. Vaccination of mice with recombinant Vlp7 with adjuvant elicited antibodies that bound to fixed whole cells of serotype 7 and to Vlp7 in Western blots, but these antibodies did not inhibit the growth of serotype 7 in vitro and did not provide protection against an infectious challenge with serotype 7. The study established that a Vlp protein was the target of a neutralizing antibody response, and it also indicated that the conformation and/or the native topology of Vlp were important for eliciting that immunity.

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Anti-CD3 Antibody Treatment Reduces Scar Formation in a Rat Model of Myocardial Infarction

Cells ◽

10.3390/cells9020295 ◽

2020 ◽

Vol 9 (2) ◽

pp. 295 ◽

Cited By ~ 2

Author(s):

Bernhard Wernly ◽

Vera Paar ◽

Achim Aigner ◽

Patrick M Pilz ◽

Bruno K Podesser ◽

...

Keyword(s):

Myocardial Infarction ◽

T Cell ◽

Rat Model ◽

Mirna Expression ◽

Cell Epitope ◽

Enzyme Linked Immunosorbent Assay ◽

Antibody Treatment ◽

Scar Size

Introduction: Antibody treatment with anti-thymocyte globulin (ATG) has been shown to be cardioprotective. We aimed to evaluate which single anti-T-cell epitope antibody alters chemokine expression at a level similar to ATG and identified CD3, which is a T-cell co-receptor mediating T-cell activation. Based on these results, the effects of anti-CD3 antibody treatment on angiogenesis and cardioprotection were tested in vitro and in vivo. Methods: Concentrations of IL-8 and MCP-1 in supernatants of human peripheral blood mononuclear cell (PBMC) cultures following distinct antibody treatments were evaluated by Enzyme-linked Immunosorbent Assay (ELISA). In vivo, anti-CD3 antibodies or vehicle were injected intravenously in rats subjected to acute myocardial infarction (AMI). Chemotaxis and angiogenesis were evaluated using tube and migration assays. Intracellular pathways were assessed using Western blot. Extracellular vesicles (EVs) were quantitatively evaluated using fluorescence-activated cell scanning, exoELISA, and nanoparticle tracking analysis. Also, microRNA profiles were determined by next-generation sequencing. Results: Only PBMC stimulation with anti-CD3 antibody led to IL-8 and MCP-1 changes in secretion, similar to ATG. In a rat model of AMI, systemic treatment with an anti-CD3 antibody markedly reduced infarct scar size (27.8% (Inter-quartile range; IQR 16.2–34.9) vs. 12.6% (IQR 8.3–27.2); p < 0.01). The secretomes of anti-CD3 treated PBMC neither induced cardioprotective pathways in cardiomyocytes nor pro-angiogenic mechanisms in human umbilical vein endothelial cell (HUVECs) in vitro. While EVs quantities remained unchanged, PBMC incubation with an anti-CD3 antibody led to alterations in EVs miRNA expression. Conclusion: Treatment with an anti-CD3 antibody led to decreased scar size in a rat model of AMI. Whereas cardioprotective and pro-angiogenetic pathways were unaltered by anti-CD3 treatment, qualitative changes in the EVs miRNA expression could be observed, which might be causal for the observed cardioprotective phenotype. We provide evidence that EVs are a potential cardioprotective treatment target. Our findings will also provide the basis for a more detailed analysis of putatively relevant miRNA candidates.

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The El Tor Biotype of Vibrio cholerae Exhibits a Growth Advantage in the Stationary Phase in Mixed Cultures with the Classical Biotype

Journal of Bacteriology ◽

10.1128/jb.01180-09 ◽

2009 ◽

Vol 192 (4) ◽

pp. 955-963 ◽

Cited By ~ 18

Author(s):

Subhra Pradhan ◽

Amit K. Baidya ◽

Amalendu Ghosh ◽

Kalidas Paul ◽

Rukhsana Chowdhury

Keyword(s):

Amino Acids ◽

Stationary Phase ◽

Vibrio Cholerae ◽

Competitive Growth ◽

Small Peptides ◽

Ileal Loop ◽

Infant Mouse ◽

Culture Filtrates ◽

El Tor

ABSTRACT Vibrio cholerae strains of the O1 serogroup that typically cause epidemic cholera can be classified into two biotypes, classical and El Tor. The El Tor biotype emerged in 1961 and subsequently displaced the classical biotype as a cause of cholera throughout the world. In this study we demonstrate that when strains of the El Tor and classical biotypes were cocultured in standard LB medium, the El Tor strains clearly had a competitive growth advantage over the classical biotype starting from the late stationary phase and could eventually take over the population. The classical biotype produces extracellular protease(s) in the stationary phase, and the amounts of amino acids and small peptides in the late stationary and death phase culture filtrates of the classical biotype were higher than those in the corresponding culture filtrates of the El Tor biotype. The El Tor biotype cells could utilize the amino acids more efficiently than the classical biotype under the alkaline pH of the stationary phase cultures but not in medium buffered to neutral pH. The growth advantage of the El Tor biotype was also observed in vivo using the ligated rabbit ileal loop and infant mouse animal models.

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Upregulation of virulence genes promotes Vibrio cholerae biofilm hyperinfectivity

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1916571117 ◽

2020 ◽

Vol 117 (20) ◽

pp. 11010-11017 ◽

Cited By ~ 6

Author(s):

A. L. Gallego-Hernandez ◽

W. H. DePas ◽

J. H. Park ◽

J. K. Teschler ◽

R. Hartmann ◽

...

Keyword(s):

Vibrio Cholerae ◽

Three Dimensional ◽

Planktonic Cells ◽

Infant Mouse ◽

Enhanced Production ◽

Quantitative Image ◽

Virulence Factor Gene ◽

Colonization Patterns

Vibrio cholerae remains a major global health threat, disproportionately impacting parts of the world without adequate infrastructure and sanitation resources. In aquatic environments, V. cholerae exists both as planktonic cells and as biofilms, which are held together by an extracellular matrix. V. cholerae biofilms have been shown to be hyperinfective, but the mechanism of hyperinfectivity is unclear. Here we show that biofilm-grown cells, irrespective of the surfaces on which they are formed, are able to markedly outcompete planktonic-grown cells in the infant mouse. Using an imaging technique designed to render intestinal tissue optically transparent and preserve the spatial integrity of infected intestines, we reveal and compare three-dimensional V. cholerae colonization patterns of planktonic-grown and biofilm-grown cells. Quantitative image analyses show that V. cholerae colonizes mainly the medial portion of the small intestine and that both the abundance and localization patterns of biofilm-grown cells differ from that of planktonic-grown cells. In vitro biofilm-grown cells activate expression of the virulence cascade, including the toxin coregulated pilus (TCP), and are able to acquire the cholera toxin-carrying CTXФ phage. Overall, virulence factor gene expression is also higher in vivo when infected with biofilm-grown cells, and modulation of their regulation is sufficient to cause the biofilm hyperinfectivity phenotype. Together, these results indicate that the altered biogeography of biofilm-grown cells and their enhanced production of virulence factors in the intestine underpin the biofilm hyperinfectivity phenotype.

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Humans surviving cholera develop antibodies against Vibrio cholerae O-specific polysaccharide that inhibit pathogen motility

10.1101/2020.10.08.332551 ◽

2020 ◽

Author(s):

Richelle C. Charles ◽

Meagan Kelly ◽

Jenny M. Tam ◽

Aklima Akter ◽

Motaher Hossain ◽

...

Keyword(s):

Monoclonal Antibodies ◽

Vibrio Cholerae ◽

Polyclonal Antibody ◽

High Speed ◽

Polyclonal Antibodies ◽

Intestinal Lumen ◽

Dependent Manner ◽

Specific Antibodies ◽

Specific Polysaccharide

ABSTRACTThe mechanism of protection against cholera afforded by previous illness or vaccination is currently unknown. We have recently shown that antibodies targeting O-specific polysaccharide (OSP) of Vibrio cholerae correlate highly with protection against cholera. V. cholerae is highly motile and possesses a flagellum sheathed in O-specific polysaccharide (OSP), and motility of V. cholerae correlates with virulence. Using high speed video microscopy, and building upon previous animal-related work, we demonstrate that sera, polyclonal antibody fractions, and OSP-specific monoclonal antibodies recovered from humans surviving cholera block V. cholerae motility at both subagglutinating and agglutinating concentrations. This anti-motility effect is reversed by pre-adsorbing sera and polyclonal antibody fractions with purified OSP; and is associated with OSP-specific but not flagellin-specific monoclonal antibodies. F[ab] fragments of OSP-specific polyclonal antibodies do not inhibit motility, suggesting a requirement for antibody-mediated crosslinking in motility inhibition. We show that OSP-specific antibodies do not directly affect V. cholerae viability, but that OSP-specific monoclonal antibody highly protects against death in the murine cholera model. We used in vivo competitive index studies to demonstrate that OSP-specific antibodies impede colonization and survival of V. cholerae in intestinal tissues, and that this impact is motility-dependent. Our findings suggest that the impedance of motility by antibodies targeting V. cholerae OSP contributes to protection against cholera.IMPORTANCECholera is a severe dehydrating illness of humans caused by Vibrio cholerae. V. cholerae is a highly motile bacterium that has a single flagellum covered in lipopolysaccharide (LPS) displaying O-specific polysaccharide (OSP), and V. cholerae motility correlates with its ability to cause disease. The mechanisms of protection against cholera are not well understood; however, since V. cholerae is a non-invasive intestinal pathogen, it is likely that antibodies that bind the pathogen or its products in the intestinal lumen contribute to protection from infection. Here, we demonstrate that OSP-specific antibodies isolated from humans surviving cholera in Bangladesh inhibit V. cholerae motility and are associated with protection against challenge in a motility-dependent manner.

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Characterization of Ferric and Ferrous Iron Transport Systems in Vibrio cholerae

Journal of Bacteriology ◽

10.1128/jb.00626-06 ◽

2006 ◽

Vol 188 (18) ◽

pp. 6515-6523 ◽

Cited By ~ 70

Author(s):

Elizabeth E. Wyckoff ◽

Alexandra R. Mey ◽

Andreas Leimbach ◽

Carolyn F. Fisher ◽

Shelley M. Payne

Keyword(s):

Vibrio Cholerae ◽

Transport System ◽

Iron Transport ◽

Iron Acquisition ◽

Shigella Flexneri ◽

Transport Systems ◽

Infant Mouse ◽

Mouse Intestine ◽

Dependent Transport

ABSTRACT Vibrio cholerae has multiple iron acquisition systems, including TonB-dependent transport of heme and of the catechol siderophore vibriobactin. Strains defective in both of these systems grow well in laboratory media and in the infant mouse intestine, indicating the presence of additional iron acquisition systems. Previously uncharacterized potential iron transport systems, including a homologue of the ferrous transporter Feo and a periplasmic binding protein-dependent ATP binding cassette (ABC) transport system, termed Fbp, were identified in the V. cholerae genome sequence. Clones encoding either the Feo or the Fbp system exhibited characteristics of iron transporters: both repressed the expression of lacZ cloned under the control of a Fur-regulated promoter in Escherichia coli and also conferred growth on a Shigella flexneri mutant that has a severe defect in iron transport. Two other ABC transporters were also evaluated but were negative by these assays. Transport of radioactive iron by the Feo system into the S. flexneri iron transport mutant was stimulated by the reducing agent ascorbate, consistent with Feo functioning as a ferrous transporter. Conversely, ascorbate inhibited transport by the Fbp system, suggesting that it transports ferric iron. The growth of V. cholerae strains carrying mutations in one or more of the potential iron transport genes indicated that both Feo and Fbp contribute to iron acquisition. However, a mutant defective in the vibriobactin, Fbp, and Feo systems was not attenuated in a suckling mouse model, suggesting that at least one other iron transport system can be used in vivo.

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A Vibrio cholerae Classical TcpA Amino Acid Sequence Induces Protective Antibody That Binds an Area Hypothesized To Be Important for Toxin-Coregulated Pilus Structure

Infection and Immunity ◽

10.1128/iai.72.10.6050-6060.2004 ◽

2004 ◽

Vol 72 (10) ◽

pp. 6050-6060 ◽

Cited By ~ 13

Author(s):

Ronald K. Taylor ◽

Thomas J. Kirn ◽

Michael D. Meeks ◽

Terri K. Wade ◽

William F. Wade

Keyword(s):

Amino Acid ◽

Western Blot ◽

Vibrio Cholerae ◽

Antibody Responses ◽

Protective Antibody ◽

Infant Mouse ◽

A Subunit ◽

Toxin Coregulated Pilus ◽

Strong Candidate ◽

A Site

ABSTRACT Vibrio cholerae is a gram-negative bacterium that has been associated with cholera pandemics since the early 1800s. Whole-cell, killed, and live-attenuated oral cholera vaccines are in use. We and others have focused on the development of a subunit cholera vaccine that features standardized epitopes from various V. cholerae macromolecules that are known to induce protective antibody responses. TcpA protein is assembled into toxin-coregulated pilus (TCP), a type IVb pilus required for V. cholerae colonization, and thus is a strong candidate for a cholera subunit vaccine. Polypeptides (24 to 26 amino acids) in TcpA that can induce protective antibody responses have been reported, but further characterization of their amino acid targets relative to tertiary or quaternary TCP structures has not been done. We report a refinement of the TcpA sequences that can induce protective antibody. One sequence, TcpA 15 (residues 170 to 183), induces antibodies that bind linear TcpA in a Western blot as well as weakly bind soluble TcpA in solution. These antibodies bind assembled pili at high density and provide 80 to 100% protection in the infant mouse protection assay. This is in sharp contrast to other anti-TcpA peptide sera (TcpA 11, TcpA 13, and TcpA 17) that bind very strongly in Western blot and solution assays yet do not provide protection or effectively bind TCP, as evidenced by immunoelectron microscopy. The sequences of TcpA 15 that induce protective antibody were localized on a model of assembled TCP. These sequences are centered on a site that is predicted to be important for TCP structure.

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Oxidative respiration through the bd-I and cbb3 oxidases is required for Vibrio cholerae pathogenicity and proliferation in vivo.

10.1101/2021.11.11.468188 ◽

2021 ◽

Author(s):

Andrew John Van Alst ◽

Lucas Maurice Demey ◽

Victor DiRita

Keyword(s):

Vibrio Cholerae ◽

Anaerobic Respiration ◽

Bacterial Pathogen ◽

Population Expansion ◽

Amplicon Sequencing ◽

Electron Acceptors ◽

Infant Mouse ◽

Small Intestinal ◽

Oxidative Respiration

Vibrio cholerae respires both aerobically and anaerobically and, while oxygen may be available to it during infection, other terminal electron acceptors are proposed for population expansion during infection. Unlike gastrointestinal pathogens that stimulate significant inflammation leading to elevated levels of oxygen or alternative terminal electron acceptors, V. cholerae infections are not understood to induce a notable inflammatory response. To ascertain the respiration requirements of V. cholerae during infection, we used Multiplex Genome Editing by Natural Transformation (MuGENT) to create V. cholerae strains lacking aerobic or anaerobic respiration. V. cholerae strains lacking aerobic respiration were attenuated in infant mice 10 5 -fold relative to wild type, while strains lacking anaerobic respiration had no colonization defect, contrary to earlier work suggesting a role for anaerobic respiration during infection. Using several approaches, including one we developed for this work termed Comparative Multiplex PCR Amplicon Sequencing (CoMPAS), we determined that the bd-I and cbb3 oxidases are essential for small intestinal colonization of V. cholerae in the infant mouse. The bd-I oxidase was also determined as the primary oxidase during growth outside the host, making V. cholerae the only example of a Gram-negative bacterial pathogen in which a bd-type oxidase is the primary oxidase for energy acquisition inside and outside of a host.

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