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1.
Nat Commun ; 11(1): 851, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-32051408

RESUMO

Lipopolysaccharide (LPS) O-antigen (O-Ag) is known to limit antibody binding to surface antigens, although the relationship between antibody, O-Ag and other outer-membrane antigens is poorly understood. Here we report, immunization with the trimeric porin OmpD from Salmonella Typhimurium (STmOmpD) protects against infection. Atomistic molecular dynamics simulations indicate this is because OmpD trimers generate footprints within the O-Ag layer sufficiently sized for a single IgG Fab to access. While STmOmpD differs from its orthologue in S. Enteritidis (SEn) by a single amino-acid residue, immunization with STmOmpD confers minimal protection to SEn. This is due to the OmpD-O-Ag interplay restricting IgG binding, with the pairing of OmpD with its native O-Ag being essential for optimal protection after immunization. Thus, both the chemical and physical structure of O-Ag are key for the presentation of specific epitopes within proteinaceous surface-antigens. This enhances combinatorial antigenic diversity in Gram-negative bacteria, while reducing associated fitness costs.


Assuntos
Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/imunologia , Imunização , Antígenos O/imunologia , Salmonella typhimurium/imunologia , Animais , Anticorpos Antibacterianos/sangue , Formação de Anticorpos , Especificidade de Anticorpos , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteção Cruzada , Modelos Animais de Doenças , Epitopos/química , Epitopos/imunologia , Imunoglobulina G/sangue , Camundongos , Modelos Moleculares , Antígenos O/química , Antígenos O/genética , Porinas/química , Porinas/genética , Porinas/imunologia , Conformação Proteica , Salmonelose Animal/imunologia , Salmonelose Animal/prevenção & controle , Análise de Sequência de Proteína
2.
Mol Immunol ; 118: 40-51, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31841966

RESUMO

To further elucidate the roles of T and B lymphocytes in fish subunit and DNA candidate vaccines for immunisation, the immune responses of T and B lymphocytes to recombinant protein (rOmpK) and plasmid OmpK (pOmpK) from Vibrio anguillarum plus cyclosporine A (CsA) were investigated in flounder (Paralichthys olivaceus). The results showed that in the rOmpK-immunised groups, the percentages of CD4-1+ and CD4-2+ T (PCD4-1+ and PCD4-2+ T) lymphocytes significantly increased to a peak on days 5 or 7. The percentages of IgM+ B (PIgM+ B) lymphocytes and specific antibodies markedly increased to a peak at weeks 4 or 5. The nine immune-related genes were significantly up-regulated and the expression levels of CD4-1, CD4-2 and MHC II genes were higher than that of CD8α, CD8ß and MHC I genes. The CD4+ T lymphocytes, IgM+ B lymphocytes, and specific antibodies were significantly inhibited by CsA. Therefore, the responses of CD4+ T lymphocytes influenced the responses of the B lymphocytes and antibodies. In the pOmpK-immunised groups, the PCD4-1+, PCD4-2+, and PCD8ß+ T lymphocytes significantly increased to a peak on days 11 or 14, days 9 or 11, and days 7 or 9, respectively. The PIgM+ B lymphocytes and specific antibodies significantly increased to a peak at weeks 5 or 6. Immune related genes upregulated, and CD4+ and CD8+ T lymphocytes, IgM+ B lymphocytes and specific antibodies all suppressed by CsA, suggesting that the responses of T lymphocytes subpopulations influenced B lymphocytes and antibodies responses. Therefore, the subpopulations of T lymphocytes played an important role in the immune responses induced by subunit and DNA candidate vaccines of OmpK and regulated the immune responses of B lymphocytes in flounder.


Assuntos
Linfócitos B/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Linguado/imunologia , Subpopulações de Linfócitos T/imunologia , Vacinas de DNA/imunologia , Vacinas de Subunidades/imunologia , Vibrio/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Linguado/microbiologia , Imunização/métodos , Vacinação/métodos , Vibrioses/imunologia , Vibrioses/microbiologia
3.
Food Chem ; 309: 125690, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-31711808

RESUMO

In this work a new fluorescence immunosensor with use of graphene oxide and graphene quantum dot for detection Campylobacter jejuni whole cell in food samples was designed. This biosensor was designed based on interaction of poly clonal antibody conjugated with graphene quantum dot with surface protein in Campylobacter jejuni cell membrane. Specific binding of graphene quantum dot with Campylobacter jejuni membrane leads to generate a distance among graphene dot and graphene oxide and fluorescence is ON. In lack of Campylobacter jejuni or in existence of other bacterial cells, distance between of graphene dot and graphene oxide is very low and graphene quantum dot fluorescence emission was OFF. Experiment revealed that step by step increase in bacterial target cells caused to gradually increased fluorescence emission and this process was linear. Limit of detection for this bacterial sensor was 10 CFU/ml and ability of this FRET immunosensor for Campylobacter jejuni sensing in comparison with other bacterial cells was significant. Also, this method for monitoring Campylobacter jejuni in poultry liver was applied and results revealed that this immunosensor could be used for analysis bacterial cell in food samples.


Assuntos
Técnicas Biossensoriais/métodos , Campylobacter jejuni/isolamento & purificação , Grafite/química , Pontos Quânticos/química , Animais , Anticorpos Antibacterianos/química , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Campylobacter jejuni/metabolismo , Transferência Ressonante de Energia de Fluorescência , Microbiologia de Alimentos , Limite de Detecção , Fígado/microbiologia , Aves Domésticas/microbiologia
4.
Emerg Microbes Infect ; 8(1): 1711-1720, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31769735

RESUMO

Among the factors associated with the resurgence of whooping cough, special emphasis has been given to pathogen adaptation after the introduction of the acellular vaccine (ACV). To assess the impact of the vaccine transition strategy from whole-cell vaccine (WCV) to ACV on population dynamics of Bordetella pertussis in Barcelona (Spain), we studied 339 isolates collected from 1986 to 2015 by PFGE and multi-locus variable-number tandem repeat analysis (MLVA). Additionally, allelic variants for the pertussis toxin and its promoter, pertactin, type 3 fimbriae and fimbrial serotyping were assessed to determine its antigenic drift. A shift was observed in the B. pertussis population as well as in its antigenic profile concurrently with the introduction of ACV in Barcelona. Four out of the five most prevalent PFGE profiles were replaced by new profiles following the ACV introduction. MLVA type 27 was the dominant genotype, and its frequency increased from 25% to 79.3% after WCV replacement. Antigen typing demonstrated the emergence of prn2, ptxP3, fim3-2 and a shift from the fimbriae 3 to the fimbriae 2 serotypes after the ACV introduction. Our findings support the presence of population and antigenic dynamic changes in B. pertussis likely driven by the introduction of ACV.


Assuntos
Variação Antigênica , Vacinas Bacterianas/imunologia , Bordetella pertussis/imunologia , Coqueluche/microbiologia , Proteínas da Membrana Bacteriana Externa/administração & dosagem , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Bordetella pertussis/genética , Genótipo , Humanos , Repetições Minissatélites , Dinâmica Populacional , Espanha , Fatores de Virulência de Bordetella/administração & dosagem , Fatores de Virulência de Bordetella/genética , Fatores de Virulência de Bordetella/imunologia , Coqueluche/prevenção & controle
5.
Fish Shellfish Immunol ; 94: 723-729, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31580933

RESUMO

Photobacteriosis caused by Photobacterium damselae subsp. piscicida (Pdp) remains one of the main infectious diseases affecting cultured fish in Mediterranean countries. Diverse vaccine formulations based in the use of inactivated bacterial cells have been used with unsatisfactory results, especially in newly cultured species like sole (Solea senegalensis). In this work, we describe the use of the outer membrane receptor (FrpA) of the siderophore piscibactin produced by Pdp as a novel subunit vaccine against photobacteriosis. FrpA has been cloned and expressed in Escherichia coli under an arabinose-inducible promoter. A recombinant protein (rFrpA) containing the pelB localization signal and a His tag was constructed to obtain a pure native form of the protein from E. coli outer membranes. The immunogenicity of rFrpA, and its protective effect against photobacteriosis, was tested by i.p. injection of 30  µg of the protein, mixed with Freund's adjuvant, in sole fingerlings with two immunizations separated by 30 days. Results showed that using either pure rFrpA or whole cells as immobilized antigens in ELISA assays, rFrpA induces the production of specific antibodies in sole. An experimental infection using fish vaccinated with rFrpA or formalin-killed whole cells of Pdp showed that both groups were protected against Pdp infection at similar levels, with no significant differences, reaching RPS values of 73% and 79%, respectively. Thus, FrpA constitutes a promising antigen candidate for the development of novel more effective vaccines against fish photobacteriosis.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vacinas Bacterianas/administração & dosagem , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Photobacterium/imunologia , Animais , Linguados , Infecções por Bactérias Gram-Negativas/prevenção & controle , Receptores de Superfície Celular/imunologia , Vacinas de Subunidades/administração & dosagem
7.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31548319

RESUMO

Antibodies are essential for immunity against Ehrlichia chaffeensis, and protective mechanisms involve blocking of ehrlichial attachment or complement and Fcγ-receptor-dependent destruction. In this study, we determined that major outer membrane protein 1 (OMP-19) hypervariable region 1 (HVR1)-specific human monoclonal antibodies (huMAbs) are protective through conventional extracellular neutralization and, more significantly, through a novel intracellular TRIM21-mediated mechanism. Addition of OMP-1-specific huMAb EHRL-15 (IgG1) prevented infection by blocking attachment/entry, a mechanism previously reported; conversely, OMP-1-specific huMAb EHRL-4 (IgG3) engaged intracellular TRIM21 and initiated an immediate innate immune response and rapid intracellular degradation of ehrlichiae. EHRL-4-TRIM21-mediated inhibition was significantly impaired in TRIM21 knockout THP-1 cells. EHRL-4 interacted with cytosolic Fc receptor TRIM21, observed by confocal microscopy and confirmed by co-immunoprecipitation. E. chaffeensis-EHRL-4-TRIM21 complexes caused significant upregulation of proinflammatory cytokine/chemokine transcripts and resulted in rapid (<30 min) nuclear accumulation of NF-κB and TRIM21 and ehrlichial destruction. We investigated the role of TRIM21 in the autophagic clearance of ehrlichiae in the presence of EHRL-4. Colocalization between EHRL-4-opsonized ehrlichiae, polyubiquitinated TRIM21, autophagy regulators (ULK1 and beclin 1) and effectors (LC3 and p62), and lysosome-associated membrane protein 2 (LAMP2) was observed. Moreover, autophagic flux defined by conversion of LC3I to LC3II and accumulation and degradation of p62 was detected, and EHRL-4-mediated degradation of E. chaffeensis was abrogated by the autophagy inhibitor 3-methyladenine. Our results demonstrate that huMAbs are capable of inhibiting E. chaffeensis infection by distinct effector mechanisms: extracellularly by neutralization and intracellularly by engaging TRIM21, which mediates a rapid innate immune response that mobilizes the core autophagy components, triggering localized selective autophagic degradation of ehrlichiae.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Ehrlichia chaffeensis/imunologia , Ribonucleoproteínas/genética , Adenina/análogos & derivados , Adenina/farmacologia , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Antígenos de Bactérias/genética , Autofagia/imunologia , Aderência Bacteriana/genética , Sistemas CRISPR-Cas , Linhagem Celular Tumoral , Ehrlichia chaffeensis/genética , Técnicas de Inativação de Genes , Humanos , Imunidade Humoral/imunologia , NF-kappa B/genética , Células THP-1
8.
Int J Nanomedicine ; 14: 6601-6613, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496701

RESUMO

Purpose: The primary goal of the present study was to explore and evaluate the highly conserved Neisserial surface protein A (NspA) molecule, fused with truncated HBV virus-like particles (VLPs), as a candidate vaccine against the virulent Neisseria meningitidis serogroup B (NMB). Methods: NspA was inserted into the major immunodominant region of the truncated hepatitis B virus core protein (HBc; amino acids 1-144). The chimeric protein, HBc-N144-NspA, was expressed from a prokaryotic vector and generated HBc-like particles, as determined by transmission electron microscopy. Further, the chimeric protein and control proteins were used to immunize mice and the resulting immune responses evaluated by flow cytometry, enzyme-linked immunosorbent assay, and analysis of serum bactericidal activity (SBA) titer. Results: Evaluation of the immunogenicity of the recombinant HBc-N144-NspA protein showed that it elicited the production of high levels of NspA-specific total IgG. The SBA titer of HBc-N144-NspA/F reached 1:16 2 weeks after the last immunization in BALB/c mice, when human serum complement was included in the vaccine. Immunization of HBc-N144-NspA, even without adjuvant, induced high levels of IL-4 and a high IgG1 to IgG2a ratio, confirming induction of an intense Th2 immune response. Levels of IL-17A increased rapidly in mice after the first immunization with HBc-N144-NspA, indicating the potential for this vaccine to induce a mucosal immune response. Meanwhile, the immunization of HBc-N144-NspA without adjuvant induced only mild inflammatory infiltration into the mouse muscle tissue. Conclusion: This study demonstrates that modification using HBc renders NspA a candidate vaccine, which can trigger protective immunity against NMB.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Vírus da Hepatite B/metabolismo , Infecções Meningocócicas/imunologia , Infecções Meningocócicas/prevenção & controle , Neisseria meningitidis/patogenicidade , Sorogrupo , Vírion/metabolismo , Adjuvantes Imunológicos/farmacologia , Sequência de Aminoácidos , Animais , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/ultraestrutura , Citocinas/metabolismo , Escherichia coli/metabolismo , Feminino , Imunidade , Imunização , Inflamação/patologia , Ativação Linfocitária/imunologia , Infecções Meningocócicas/patologia , Camundongos Endogâmicos BALB C , Proteínas Recombinantes/imunologia , Teste Bactericida do Soro , Baço/microbiologia , Linfócitos T/imunologia , Vacinação , Virulência
9.
APMIS ; 127(12): 753-763, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31512768

RESUMO

Iron uptake system is expressed in early stages of Acinetobacter baumannii infections under iron-restricted conditions. This study is aimed at the evaluation of immuno-protectivity of BfnH in comparison with BauA in both mature and selected fragmental proteins. The study was designed in single and combined forms of antigens. BfnH is presented in 3472 strains of A. baumannii with more than 97% identity. The preliminary immune-informatics analysis of this protein indicated a region from the ß-barrel domain including exposed loops 2-5, with antigenic score comparable to that of BfnH. There was a significant rise in the specific IgG response in all test groups. The bacterial challenge with a lethal dose of A. baumannii demonstrated partial protection of whole proteins which coincides with a significant reduction in the bacterial population colonized in the main organs and an increase in the survival level. Passive immunization of the mice brought about 50% survival in the mice groups immunized with BfnH and with a combination of BfnH and BauA. The protectivity of siderophore receptors suggests their potential immunogenic role that could be considered as a component of multivalent subunit vaccine candidates against A. baumannii.


Assuntos
Infecções por Acinetobacter/prevenção & controle , Acinetobacter baumannii/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Imunização , Receptores de Superfície Celular/imunologia , Infecções por Acinetobacter/imunologia , Infecções por Acinetobacter/microbiologia , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Carga Bacteriana , Proteínas da Membrana Bacteriana Externa/química , Proteínas da Membrana Bacteriana Externa/genética , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia , Epitopos de Linfócito B , Feminino , Imunogenicidade da Vacina , Camundongos Endogâmicos BALB C , Receptores de Superfície Celular/química , Receptores de Superfície Celular/genética
10.
APMIS ; 127(12): 797-804, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31514254

RESUMO

Brucellosis is a worldwide bacterial zoonosis caused by Brucella spp. No approved vaccine is available for human use against the disease. In this study, outer membrane vesicles (OMVs) from a Brucella melitensis biovar 1 human isolate obtained in Iran were used to immunize BALB/c mice (n = 12) by 2 intramuscular injections with a 2-week interval. Another group of 12 mice was used as non-vaccinated controls. Two weeks after the last vaccination, six mice of each group were sacrificed, and proliferation and interferon gamma (IFNγ) production responses of their splenocytes were evaluated following in vitro stimulation with killed Brucella cells. The other mice were challenged with the virulent B. melitensis isolate. Two weeks later, mice were killed and spleens were cultured to determine the number of the challenge strain. The results showed proliferative response and IFNγ production of splenocytes from vaccinated mice (stimulation index: 2.18 ± 0.57, and 1519.35 ± 10.70 pg/mL, respectively) were significantly higher than those of control mice (stimulation index: 1.02 ± 0.02, and 210.01 ± 17.58 pg/mL, respectively). Numbers of the challenge strain in spleens of vaccinated mice were also significantly less than those in the controls with 1.6 units of protection. Our study revealed vaccination with OMVs of the B. melitensis isolate could induce specific immune responses and protection against infection in the mouse model suggesting their potential application for active immunization against brucellosis.


Assuntos
Vacina contra Brucelose/imunologia , Brucella melitensis/imunologia , Brucelose/imunologia , Brucelose/prevenção & controle , Vesículas Extracelulares/imunologia , Animais , Proteínas da Membrana Bacteriana Externa/imunologia , Brucella melitensis/citologia , Brucelose/microbiologia , Modelos Animais de Doenças , Feminino , Humanos , Imunidade Celular , Interferon gama/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Baço/metabolismo , Baço/microbiologia , Vacinação
11.
Vet Microbiol ; 236: 108367, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31500727

RESUMO

Avian pathogenic Escherichia coli (APEC) typically causes colibacillosis and is a major concern for the poultry industry and public health. As a vaccine platform, the outer membrane vesicles (OMVs) derived from various gram-negative bacteria and even some gram-positive bacteria have been reported to be immunogenic in laboratories or upon commercial usage worldwide. Here, we purified OMVs from APEC serotype O78 strain by ultracentrifugation and gradient isolation. By SDS-PAGE and LC-MS/MS analysis, the 20 most abundant proteins located on OMVs were identified and analyzed; the lipopolysaccharide (LPS) profiles of OMVs were not different from those of the bacteria. Moreover, three groups of chickens were immunized with OMV-, outer membrane protein (OMP)- and PBS, with the latter two serving as positive and negative controls, respectively. By analyzing the anti-OMP and anti-LPS IgG titers stimulated by the tested vaccine candidates, the macrophage opsonophagocytic activity and the bactericidal activity mediated by serum antibodies in vaccinated chickens, we found that the OMV-vaccinated chicken group was superior to the two other groups. These findings were confirmed by additional chicken challenge tests, in which all OMV-vaccinated group chickens obtained complete protection but those of the other two groups were barely protected. Our data demonstrate that native APEC O78 OMVs can induce protective immunity in chickens and therefore be used as a candidate vaccine for APEC serotype O78 strain infections.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Galinhas , Infecções por Escherichia coli/veterinária , Vacinas contra Escherichia coli/imunologia , Escherichia coli/imunologia , Doenças das Aves Domésticas/prevenção & controle , Animais , Anticorpos Antibacterianos/sangue , Infecções por Escherichia coli/prevenção & controle , Doenças das Aves Domésticas/microbiologia
12.
Microb Pathog ; 135: 103661, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400445

RESUMO

Treponema (T.) denticola is one of the key etiological agents in the development of periodontitis. The major outer sheath protein (Msp) of T. denticola has been shown to mediate pathogenesis and to facilitate adhesion of T. denticola to mucosal surfaces. This study aimed to find short polypeptides in the amino acid sequence of Msp which may be immunogenic and might elicit protective antisera against T. denticola. The complete msp sequence was divided into six fragments and the corresponding genes were cloned and expressed. Antisera against the polypeptides were raised in rabbits and fragment 3 (F3), hereinafter called PerioVax3 was the most potent fragment of the Msp in terms of yielding high titer antiserum. An adhesion assay was done to examine the inhibitory effects of antisera on the attachment of T. denticola to human gingival fibroblasts (HGFs) and human fibronectin. Antiserum against PerioVax3 significantly inhibited attachment of T. denticola to the substratum. Also, antiserum against PerioVax3 inhibited detachment of HGFs upon T. denticola exposure. To begin examining the clinical relevance of this work, blood samples from 12 sever periodontitis patients were collected and the sera were used in western blotting against the recombinant polypeptides. Periodontitis patient antisera exclusively detected PerioVax3 in western blotting. The data suggest that PerioVax3 carries epitopes that may trigger humoral immunity against T. denticola, which may protect against its adhesion functions. The complexity of periodontitis suggests that PerioVax3 may be considered for testing as a component of an experimental multivalent periodontal vaccine in further preclinical and clinical studies.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Epitopos/imunologia , Periodontite/imunologia , Treponema denticola/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/farmacologia , Antígenos de Bactérias/sangue , Antígenos de Bactérias/genética , Aderência Bacteriana/efeitos dos fármacos , Aderência Bacteriana/imunologia , Proteínas da Membrana Bacteriana Externa/sangue , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Bactérias/genética , Linhagem Celular , Clonagem Molecular , Modelos Animais de Doenças , Fibroblastos , Fibronectinas , Humanos , Masculino , Periodontite/sangue , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Treponema denticola/genética , Vacinas , Fatores de Virulência/imunologia
13.
Vet Microbiol ; 235: 188-194, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31383301

RESUMO

Outer membrane vesicles (OMVs) are produced and secreted virtually by every known Gram-negative bacterium. Despite their non-live nature, they share antigenic characteristics with the bacteria they originate from. This, together with their relative ease of purification, casts the OMVs as a very promising and flexible tool in both human and veterinary vaccinology. The aim of the current work was to get an insight into the antigenic pattern of OMVs from the pig pathogen Actinobacillus pleuropneumoniae in the context of vaccine development. Accordingly, we designed a protocol combining 2D Western Blotting and mass spectrometric identification to robustly characterize the antigenic protein pattern of the vesicles. Our analysis revealed that A. pleuropneumoniae OMVs carry several immunoreactive virulence factors. Some of these proteins, LpoA, OsmY and MIDG2331_02184, have never previously been documented as antigenic in A. pleuropneumoniae or other pathogenic bacteria. Additionally, we showed that despite their relative abundance, proteins such as FrpB and DegQ do not contribute to the antigenic profile of A. pleuropneumoniae OMVs.


Assuntos
Infecções por Actinobacillus/veterinária , Actinobacillus pleuropneumoniae/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Actinobacillus pleuropneumoniae/imunologia , Animais , Proteínas da Membrana Bacteriana Externa/genética , Western Blotting , Espectrometria de Massas , Mutação , Proteômica , Suínos , Fatores de Virulência/imunologia
14.
Comp Immunol Microbiol Infect Dis ; 66: 101328, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31437676

RESUMO

BACKGROUND: Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic mucosal human pathogen that naturally releases outer membrane vesicles (OMVs) in different environments, as do other Gram-negative bacteria. The intestinal tract infections caused by P. aeruginosa increase the risk of respiratory infections and mortality of other diseases related to gut infections. Therefore, in this study, we attempted to investigate toll-like receptor (TLR) signaling pathways and immune response profiles of human colon adenocarcinoma (Caco2) cell line exposed to the OMVs of three different P. aeruginosa strains (i.e., antibiotic-susceptible, multi-drug resistant (MDR), and standard lab ATCC 17933). MATERIALS AND METHODS: Real-time quantitative reverse transcription PCR array was carried out to determine mRNA expression in 84 TLRs signaling pathway genes, and the production of specific cytokines was measured by ELISA. RESULTS: OMVs of different strains could induce unique changes in regulating TLRs signaling pathways, such that there were remarkable differences in pro-inflammatory effects and anti-inflammatory responses among the three strains. CONCLUSION: The more complete immune responses observed through the MAMPs caused by MDR strain OMVs interactions with Caco2 lead us to the conclusion that the use of MDR or cystic fibrosis strain OMVs for better known the host immune responses seems preferable.


Assuntos
Proteínas da Membrana Bacteriana Externa/imunologia , Células Epiteliais/imunologia , Pseudomonas aeruginosa/imunologia , Transdução de Sinais/imunologia , Receptores Toll-Like/imunologia , Células CACO-2 , Humanos , Receptores Toll-Like/genética
15.
Biomed Res Int ; 2019: 3768948, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31467887

RESUMO

This systematic review describes what "the cutting edge vaccines for Aeromonas hydrophila are". The focus is on types of high tech biotechnological based vaccines, target gene or antigen in developing these vaccines, and challenge model fish species used in vaccines efficacy testing. Vaccines delivery methods, immune response, and their efficacy, adjuvant or carrier systems used, and the overall experimental setup or design of the vaccines under investigation are also described. The search for the original papers published between 2009 and 2018 was conducted in June of 2018, using the PubMed and Google scholar electronic database. Twenty-three (23/4386) studies were included in the final assembly using PRISMA guidelines (Protocol not registered). Recombinant protein vaccines were the highly experimented type of the modern biotechnological based vaccines identified in the selected studies (16/23; 70%). Outer membrane proteins (OMPs) of different ß-barrels were shown to be a potential antigenic entity for A. hydrophila vaccines (57%). Intraperitoneal route with conventional carries or adjuvants was the highly applied delivery system while very few studies used herbal based vaccine adjuvants and nanomaterial as a vaccine carrier. Variation was observed in terms of protection levels in the selected studies. The experimental designs partly contributed to the observed variation. Therefore, recombinant vaccines that use new carrier system technologies and delivered through oral route in feeds would have been of great value for use in the prevention and control of A. hydrophila infections in fish. Despite the usefulness as academic tools to identify what is important in pathogenicity of the etiological agent to the host fish, these vaccines are only economically viable in very high-value animals. Therefore, if vaccination is a good option for A. hydrophila group, then simple autogenous vaccines based on accurate typing and evidence-based definition of the epidemiological unit for their use would be the most viable approach in terms of both efficacy and economic feasibility especially in low and middle-income countries (LMIC).


Assuntos
Aquicultura , Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/prevenção & controle , Aeromonas hydrophila/efeitos dos fármacos , Aeromonas hydrophila/patogenicidade , Animais , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas da Membrana Bacteriana Externa/uso terapêutico , Vacinas Bacterianas/genética , Biotecnologia/métodos , Doenças dos Peixes/microbiologia , Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos
16.
Comp Immunol Microbiol Infect Dis ; 65: 176-180, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31300110

RESUMO

Veterinary leptospirosis vaccines are composed of bacterins and present limitations, for example, the need for bacteriological culture and serovar-dependent immunity. Recombinant antigens represent a promising alternative. LigAni, LigBrep, and LipL32 proteins have been shown to promote a protective immune response against the homologous challenge in hamsters. Therefore, the next step is to evaluate the immunological properties of these immunogens in the actual hosts, as ruminants, which has never been performed before. The objective of this study was to evaluate the immunogenicity and potential adverse effects of the recombinant proteins LigAni, LigBrep, and LipL32 in the ovine model. For this, 16 Santa Inês sheep were allocated into three groups: two experimental (Groups A and B) and one control group (Group C). Group A was inoculated with a formulation containing the recombinant proteins in combination with the aluminum hydroxide adjuvant; Group B was inoculated with a formulation containing the recombinant proteins in combination with the Montanide adjuvant; and Group C was inoculated with adjuvants only. The results revealed that formulations containing the recombinant proteins induced total IgG seroconversion and led to a significant increase in antibody titers in the sheep model. Besides, there were no clinical changes or adverse effects. Thus, LigAni, LigBrep, and LipL32 proteins elicited a significant humoral immune response with elevated serum IgG levels, demonstrating that they possess the immunogenic and safety characteristics necessary to sustain their potential use as leptospirosis vaccines in the ruminant model.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Imunogenicidade da Vacina , Leptospira/imunologia , Leptospirose/veterinária , Adjuvantes Imunológicos , Animais , Antígenos de Bactérias/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Bactérias/genética , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Modelos Animais de Doenças , Feminino , Imunidade Humoral , Leptospira/genética , Leptospirose/imunologia , Leptospirose/prevenção & controle , Proteínas Recombinantes/imunologia , Ovinos , Vacinas Sintéticas/imunologia
17.
PLoS One ; 14(7): e0217661, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31291256

RESUMO

A primary challenge in developing effective vaccines against obligate, intracellular, bacterial tick-borne pathogens that establish persistent infection is the identification of antigens that cross protect against multiple strains. In the case of Anaplasma marginale, the most prevalent tick-borne pathogen of cattle found worldwide, OmpA is an adhesin and thus a promising vaccine candidate. We sequenced ompA from cattle throughout Ghana naturally infected with A. marginale in order to determine the degree of variation in this gene in an area of suspected high genetic diversity. We compared the Ghanaian sequences with those available from N. America, Mexico, Australia and Puerto Rico. When considering only amino acid changes, three unique Ghanaian OmpA variants were identified. In comparison, strains from all other geographic regions, except one, shared a single OmpA variant, Variant 1, which differed from the Ghanaian variants. Next, using recombinant OmpA based on Variant 1, we determined that amino acid differences in OmpA in Ghanaian cattle as compared to OmpA Variant 1 did not alter the binding capacity of antibody directed against OmpA Variant 1, supporting the value of OmpA as a highly conserved vaccine candidate.


Assuntos
Substituição de Aminoácidos , Anaplasma marginale/genética , Anaplasmose/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Doenças dos Bovinos/microbiologia , Anaplasma marginale/imunologia , Anaplasmose/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Gana , Polimorfismo de Nucleotídeo Único
18.
PLoS Negl Trop Dis ; 13(7): e0007511, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31269021

RESUMO

The prevalence of rheumatic heart disease (RHD) in the Aboriginal population of the Australian Northern Territory is high, and Streptococcus pyogenes skin infections likely contribute to this. A promising candidate S. pyogenes "30mer" vaccine is composed of 30 pharyngitis associated type-specific antigens from the S. pyogenes M protein. Cross opsonisation experiments suggest that 30mer vaccine protection may extend to non-cognate emm types. A new "emm cluster" scheme for classifying M protein is based on the full-length coding sequence, and correlates with functional and immunological properties, and anatomical tropism. Twenty-seven years of research in the Northern Territory has yielded 1810 S. pyogenes isolates with clinical and emm type data. The primary aim was to analyse these data with reference to the emm cluster scheme and cross opsonisation information, to inform estimation of 30mer vaccine efficacy in the Northern Territory. The isolates encompass 101 emm types. Variants of cluster A-C were enriched in throat isolates, and variants of emm cluster D enriched in skin isolates. Throat isolates were enriched for 30mer vaccine cognate emm types in comparison with skin isolates of which only 25% were vaccine emm types. While cross opsonisation data indicates potential for enhancing 30mer vaccine coverage, more than one third of skin isolates were within 38 emm types untested for cross opsonisation. Emm cluster D variants, in particular emm cluster D4, were not only all non-cognate with the vaccine, but were abundant and diverse, and less likely to be cross-opsonisation positive than other emm clusters. Long term persistence of many emm types in the study area was revealed. It was concluded that the 30mer vaccine efficacy in the Northern Territory will likely require both cross protection, and additional measures to elicit immunity against variants of emm cluster D.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/imunologia , Proteínas de Transporte/imunologia , Cardiopatia Reumática/microbiologia , Infecções Estreptocócicas/prevenção & controle , Vacinas Estreptocócicas/uso terapêutico , Streptococcus pyogenes , Humanos , Northern Territory/epidemiologia , Faringite/epidemiologia , Faringite/microbiologia , Prevalência , Cardiopatia Reumática/epidemiologia , Cardiopatia Reumática/prevenção & controle , Pele/microbiologia , Infecções Estreptocócicas/complicações , Infecções Estreptocócicas/epidemiologia , Vacinas Estreptocócicas/imunologia
19.
Infect Immun ; 87(10)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31331960

RESUMO

In this study, a novel recombinant attenuated Yersinia pseudotuberculosis PB1+ strain (χ10069) engineered with ΔyopK ΔyopJ Δasd triple mutations was used to deliver a Y. pestis fusion protein, YopE amino acid 1 to 138-LcrV (YopENt138-LcrV), to Swiss Webster mice as a protective antigen against infections by yersiniae. χ10069 bacteria harboring the pYA5199 plasmid constitutively synthesized the YopENt138-LcrV fusion protein and secreted it via the type 3 secretion system (T3SS) at 37°C under calcium-deprived conditions. The attenuated strain χ10069(pYA5199) was manifested by the establishment of controlled infection in different tissues without developing conspicuous signs of disease in histopathological analysis of microtome sections. A single-dose oral immunization of χ10069(pYA5199) induced strong serum antibody titers (log10 mean value, 4.2), secretory IgA in bronchoalveolar lavage (BAL) fluid from immunized mice, and Yersinia-specific CD4+ and CD8+ T cells producing high levels of tumor necrosis factor alpha (TNF-α), gamma interferon (IFN-γ), and interleukin 2 (IL-2), as well as IL-17, in both lungs and spleens of immunized mice, conferring comprehensive Th1- and Th2-mediated immune responses and protection against bubonic and pneumonic plague challenges, with 80% and 90% survival, respectively. Mice immunized with χ10069(pYA5199) also exhibited complete protection against lethal oral infections by Yersinia enterocolitica WA and Y. pseudotuberculosis PB1+. These findings indicated that χ10069(pYA5199) as an oral vaccine induces protective immunity to prevent bubonic and pneumonic plague, as well as yersiniosis, in mice and would be a promising oral vaccine candidate for protection against plague and yersiniosis for human and veterinary applications.


Assuntos
Anticorpos Antibacterianos/biossíntese , Imunoglobulina A/biossíntese , Vacina contra a Peste/administração & dosagem , Peste/prevenção & controle , Proteínas Recombinantes de Fusão/administração & dosagem , Yersinia pestis/efeitos dos fármacos , Infecções por Yersinia pseudotuberculosis/prevenção & controle , Yersinia pseudotuberculosis/efeitos dos fármacos , Administração Oral , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/imunologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/imunologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/microbiologia , Proteção Cruzada , Feminino , Expressão Gênica , Humanos , Imunização , Interferon gama/genética , Interferon gama/imunologia , Interleucina-2/genética , Interleucina-2/imunologia , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/microbiologia , Masculino , Camundongos , Peste/imunologia , Peste/microbiologia , Peste/mortalidade , Vacina contra a Peste/biossíntese , Vacina contra a Peste/genética , Vacina contra a Peste/imunologia , Plasmídeos/química , Plasmídeos/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/imunologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Análise de Sobrevida , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Vacinas Sintéticas , Yersinia pestis/imunologia , Yersinia pestis/patogenicidade , Yersinia pseudotuberculosis/imunologia , Yersinia pseudotuberculosis/patogenicidade , Infecções por Yersinia pseudotuberculosis/imunologia , Infecções por Yersinia pseudotuberculosis/microbiologia , Infecções por Yersinia pseudotuberculosis/mortalidade
20.
J Photochem Photobiol B ; 198: 111560, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31336216

RESUMO

Previous studies revealed significant impact on cancer cell by mid-infrared (MIR) radiation. However, the effects of narrow band MIR on immune reaction and infectious disease are still unknown. In this study, an enhanced innate immune response was observed through the interaction between Leptospiral outer membrane protein (LipL32) and toll-like receptor 2 (TLR2). Thereafter, human kidney proximal tubular cells (HK-2 cells) initiated a serial reaction of enhanced MCP-1 production. The 6 µm narrow bandwidth light source emitted by waveguide thermal emitter (WTE) was applied to induce carbonyl group (CO bond) stretching vibration during the stage of antigen-receptor complex formation. The amount of MCP-1 gene expression had 2.5 folds increase after narrow band MIR illumination comparing to non-MIR illumination at low dose LipL32 condition. Besides, both ELISA and confocal microscopy results also revealed that the chemokine concentration increased significantly after narrow band MIR illumination either at low or high concentration of LipL32. Furthermore, a specific phenomenon that narrow band MIR can amplify the signal of weak immune response by enhancing sensitivity of the interaction between antigen and receptor was observed. This study exhibits clear evidence that the narrow band MIR exposure can modulate the early immune response of infectious disease and play a potential role to develop host-directed therapy in the future.


Assuntos
Proteínas da Membrana Bacteriana Externa/farmacologia , Raios Infravermelhos , Lipoproteínas/farmacologia , Proteínas da Membrana Bacteriana Externa/imunologia , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Túbulos Renais Proximais/citologia , Túbulos Renais Proximais/efeitos dos fármacos , Túbulos Renais Proximais/metabolismo , Leptospira/metabolismo , Lipoproteínas/imunologia
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