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1.
Lett Appl Microbiol ; 70(1): 2-12, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31518435

RESUMO

Dental caries, caused by Streptococcus mutans, is a common infection. Caries vaccine has been under investigation for the last 40 years. Many in vitro and in vivo studies and some human clinical trials have determined many pertinent aspects regarding vaccine development. The virulence determinants of Strep. mutans, such as Ag I/II, responsible for adherence to surfaces, glucosyltransferase, responsible for the production of glucan, and the glucan-binding protein, responsible for the attachment of glucan to surfaces, have been known to elicit an antigen-specific immune response. It is also known that more than one antigen or a functional part of the genome responsible for these virulence determinants provide a better host response compared with the monogenic vaccine or complete genome of a specific antigen. To enhance the host response, the use of adjuvants has been studied and the routes of antigen administration have been investigated. In recent years, some promising vaccines such as pGJA-P/VAX, LT derivative/Pi39-512 , KFD2-rPAc and SBR/GBR-CMV-nirB have been developed and tested in animals. New virulence targets need to be explored. Multicentre collaborative studies and human clinical trials are required and some interest from funders and public health experts should be generated to overcome this hurdle. SIGNIFICANCE AND IMPACT OF THE STUDY: Dental caries is an irreversible, multifactorial opportunistic infection. The treatment is costly, making it a public health problem. Despite many years of promising laboratory research, animal studies and clinical trials, there is no commercially available vaccine today. The research objectives have become more refined from lessons learnt over the years. Multigenic DNA/recombinant vaccines, using the best proved adjuvants with a delivery system for the nasal or sublingual route, should be developed and researched with multicentre collaborative efforts. In addition, new vaccine targets can be identified. To overcome the economic hurdle, funders and public health interest should be stimulated.


Assuntos
Vacinas Bacterianas/imunologia , Cárie Dentária/prevenção & controle , Streptococcus mutans/imunologia , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Cárie Dentária/microbiologia , Humanos , Streptococcus mutans/genética , Streptococcus mutans/fisiologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/genética , Vacinas de DNA/imunologia
2.
Medicina (B Aires) ; 79(Spec 6/1): 552-558, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31864225

RESUMO

The proportion of adult population has increased globally and the current projections indicate that, by 2050, the group of 60 years and older will represent 21.1%. There are now vaccines exclusively designed for adults and others that are applied in early life but need to be updated later in life. Vaccines for adults are not only based on their respective age group but are also linked to risk factors like occupation, life style, health situation, among others. At the same time, longevity brings with it a weakening of the immune response to vaccines, a process known as immunosenescence representing an increasing challenge to adequately protect this age group. For some time, WHO has been promoting the term "Vaccination through the life course" allowing for an extension of the vaccination vision and taking adults as an integral part into the national vaccination programs and calendars. There are several vaccine preventable diseases affecting adults, but those associated with influenza virus and pneumococcus are the ones that affect the largest age group. Several recommendations include, additionally, others to prevent diphtheria, tetanus, whooping cough, hepatitis A and B, meningococcus, chickenpox, measles, rubella, mumps, herpes zoster, human papilloma virus and others. There are still many challenges to overcome in order to fully include adults, particularly health personnel, and to make vaccines extensively valued as a prevention tool in order to achieve a healthy life.


Assuntos
Infecções Bacterianas/prevenção & controle , Vacinas Bacterianas/administração & dosagem , Controle de Doenças Transmissíveis , Programas de Imunização , Vacinas Virais/administração & dosagem , Viroses/prevenção & controle , Adolescente , Adulto , Infecções Bacterianas/classificação , Humanos , Pessoa de Meia-Idade , Viroses/classificação , Adulto Jovem
3.
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.
BMC Infect Dis ; 19(1): 901, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31660885

RESUMO

BACKGROUND: To prospectively analyze the efficacy of uromune® in the prevention of uncomplicated recurrent urinary tract infections at 3 and 6 months, and according to gender and menopause. METHODS: From September 2011 to December 2017 uromune® was administered sublingually every 24 h along 3 months to 784 patients with history of three or more uncomplicated urinary tract infections in the 12 months prior to the first visit. The variables analyzed with statistical package system for science version 15.0 were age, gender, number of urinary tract infections with positive urine culture in the first consultation, and 3 and 6 months after the end of treatment. The results with positive urine culture were registered at 3 and 6 months after the end of the treatment according to gender and also in the menopausal group with respect to pre-menopausal women. RESULTS: Mean age was 73.5 years. 82.7% were women and 94.3% menopausal. The number of episodes of urinary tract infections in the 12 months prior to uromune® were 3 in 37.2%, 4 in 28.1%, 5 in 19.5%, 6 in 9.6%, 7 in 4%, 8 in 1.4%, 9 in 0.1% and 10 in 0.1%. Three months after uromune® 44.1% had 0 urinary tract infections and 27.6% had 1. After 6 months the results were 0 urinary tract infections in 32.3% and 1 in 32.4%. Women had 0 urinary tract infections after 3 months in 45.4% and 1 in 28.5%. At 6 months the female had 0 episodes in 32.7% and 1 in 33.2%. Menopausal women had 0 urinary tract infections at 3 months in 46.5% and 1 in 28% and at 6 months scored 0 episodes in 33.6% and 1 in 32.9%. CONCLUSIONS: Uromune® was highly effective to reduce the number of episodes of urinary tract infections at three and six months of follow-up. Uromune® reduced the number of episodes to zero or one in 71.7 and 64.7% at three and six months with minimal side effects. The best results were observed in women over 50 years old. Sublingual immunoprophylaxis with uromune® could be the treatment of first choice in the prevention of uncomplicated recurrent urinary tract infections according to the sample analyzed.


Assuntos
Vacinas Bacterianas/uso terapêutico , Infecções Urinárias/terapia , Vacinação/métodos , Administração Sublingual , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Vacinas Bacterianas/administração & dosagem , Feminino , Seguimentos , Humanos , Masculino , Menopausa , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Fatores Sexuais , Resultado do Tratamento , Infecções Urinárias/prevenção & controle , Adulto Jovem
6.
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.
Int J Nanomedicine ; 14: 8179-8193, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632026

RESUMO

Background: Chlamydia psittaci is a zoonotic bacteria closely associated with psittacosis/ornithosis. Vaccination has been recognized as the best way to inhibit the spread of C. psittaci due to the majority ignored of infections. The optimal Chlamydia vaccine was obstructed by the defect of single immunization route and the lack of availability of nontoxic and valid adjuvants. Methods: In this study, we developed a novel immunization strategy, simultaneous (SIM) intramuscular (IM) and intranasal (IN) administration of a C. psittaci antigens (Ags) adjuvanted with chitosan nanoparticles (CNPs). And SIM-CNPs-Ags were used to determine the different types of immune response and the protective role in vivo. Results: CNPs-Ags with zeta-potential values of 13.12 mV and of 276.1 nm showed excellent stability and optimal size for crossing the mucosal barrier with high 71.7% encapsulation efficiency. SIM-CPN-Ags mediated stronger humoral and mucosal responses by producing meaningfully high levels of IgG and secretory IgA (sIgA) antibodies. The SIM route also led to Ags-specific T-cell responses and increased IFN-γ, IL-2, TNF-α and IL-17A in the splenocyte supernatants. Following respiratory infection with C. psittaci, we found that SIM immunization remarkably reduced bacterial load and the degree of inflammation in the infected lungs and made for a lower level of IFN-γ, TNF-α and IL-6. Furthermore, SIM vaccination with CNPs-Ags had obviously inhibited C. psittaci disseminating to various organs in vivo. Conclusion: SIM immunization with CNPs-adjuvanted C. psittaci Ags may present a novel strategy for the development of a vaccine against the C. psittaci infection.


Assuntos
Adjuvantes Imunológicos/administração & dosagem , Vacinas Bacterianas/administração & dosagem , Quitosana/administração & dosagem , Chlamydophila psittaci/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Nanopartículas/administração & dosagem , Administração Intranasal , Animais , Antígenos de Bactérias/imunologia , Citocinas/metabolismo , Feminino , Imunidade Humoral , Imunidade nas Mucosas , Imunoglobulina G/metabolismo , Injeções Intramusculares , Pulmão/patologia , Camundongos Endogâmicos BALB C , Nanopartículas/ultraestrutura , Tamanho da Partícula , Psitacose , Baço/imunologia , Baço/microbiologia , Linfócitos T/imunologia , Vacinação
8.
J Appl Microbiol ; 127(6): 1646-1655, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31529560

RESUMO

AIMS: The outer membrane porin protein (OMPP) of Bordetella bronchiseptica is an important adhesion factor and protective immunogen. The aim of this study was to verify the immunogenicity of recombinant OMPP and its protective efficacy against a lethal challenge with B. bronchiseptica in rabbits. METHODS AND RESULTS: Soluble rOMPP was successfully expressed in Escherichia coli, and the purified recombinant protein was mixed with the ISA 201 VG adjuvant to prepare a subunit vaccine for B. bronchiseptica. Rabbits were immunized with the rOMPP subunit vaccine and then infected with the virulent B. bronchiseptica strain QDBb01. Rabbits immunized with the subunit vaccine were completely protected compared to the control group, and the protective effect was obviously better than that of the inactivated whole-cell vaccine. Moreover, analysis of the immunization duration showed that the rOMPP subunit vaccine provided immune protection for at least 4 months after the second immunization. CONCLUSIONS: The rOMPP subunit vaccine completely protected rabbits from a subsequent B. bronchiseptica challenge. SIGNIFICANCE AND IMPACT OF THE STUDY: The results will provide key information for the development of a safe and effective recombinant subunit vaccine against B. bronchiseptica in rabbits.


Assuntos
Vacinas Bacterianas/imunologia , Infecções por Bordetella/prevenção & controle , Bordetella bronchiseptica/imunologia , Porinas/imunologia , Adjuvantes Imunológicos , Animais , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/isolamento & purificação , Infecções por Bordetella/imunologia , Bordetella bronchiseptica/patogenicidade , Imunização , Porinas/genética , Porinas/isolamento & purificação , Porinas/metabolismo , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Vacinas de Subunidades
9.
Lett Appl Microbiol ; 69(5): 385-390, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529707

RESUMO

Clostridium perfringens is the main cause of sudden death in dogs and currently there is no vaccine to prevent it. In this study, a canine C. perfringens type A strain was used to prepare a vaccine. C. perfringens was inactivated by formaldehyde and adjuvants were added. The safety and immunological characteristics of the inactivated C. perfringens vaccine were evaluated in mice and dogs. The results showed that the C. perfringens vaccine was safe and had immunoprotective activity. The serum antibody titre of immunized mice reached up to 6·25 × 104 . Both single immunization of 4 ml and dual immunizations of 2 ml each provided good immune protection, with five of five immunized dogs surviving. This study also studied a detoxified crude α-toxin extract vaccine. The results showed that a single immunization with 0·5 ml of the detoxified crude α-toxin extract vaccine provided immune protection, with five of five immunized dogs surviving. The inactivated C. perfringens type A vaccine can be used to prevent canine C. perfringens infections. SIGNIFICANCE AND IMPACT OF THE STUDY: Clostridium perfringens is the main cause of sudden death in dogs and currently there is no vaccine to prevent it. In this study, an inactivated canine C. perfringens vaccine and a detoxified crude α-toxin vaccine were prepared. The safety and protective effects of these vaccines were evaluated using mouse and dog models. The vaccines were shown to be safe and to provide immune protection effects that can be used to prevent canine C. perfringens infection.


Assuntos
Toxinas Bacterianas/imunologia , Vacinas Bacterianas/imunologia , Infecções por Clostridium/prevenção & controle , Clostridium perfringens/imunologia , Animais , Toxinas Bacterianas/administração & dosagem , Toxinas Bacterianas/genética , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Infecções por Clostridium/microbiologia , Clostridium perfringens/genética , Cães , Avaliação Pré-Clínica de Medicamentos , Humanos , Imunização , Camundongos , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/genética , Vacinas de Produtos Inativados/imunologia
10.
Infect Immun ; 87(12)2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31501249

RESUMO

Coxiella burnetii, the etiological agent of Q fever, is a Gram-negative bacterium transmitted to humans by inhalation of contaminated aerosols. Acute Q fever is often self-limiting, presenting as a febrile illness that can result in atypical pneumonia. In some cases, Q fever becomes chronic, leading to endocarditis that can be life threatening. The formalin-inactivated whole-cell vaccine (WCV) confers long-term protection but has significant side effects when administered to presensitized individuals. Designing new vaccines against C. burnetii remains a challenge and requires the use of clinically relevant modes of transmission in appropriate animal models. We have developed a safe and reproducible C. burnetii aerosol challenge in three different animal models to evaluate the effects of pulmonary acquired infection. Using a MicroSprayer aerosolizer, BL/6 mice and Hartley guinea pigs were infected intratracheally with C. burnetii Nine Mile phase I (NMI) and demonstrated susceptibility as determined by measuring bacterial growth in the lungs and subsequent dissemination to the spleen. Histological analysis of lung tissue showed significant pathology associated with disease, which was more severe in guinea pigs. Infection using large-particle aerosol (LPA) delivery was further confirmed in nonhuman primates, which developed fever and pneumonia. We also demonstrate that vaccinating mice and guinea pigs with WCV prior to LPA challenge is capable of eliciting protective immunity that significantly reduces splenomegaly and the bacterial burden in spleen and lung tissues. These data suggest that these models can have appreciable value in using the LPA delivery system to study pulmonary Q fever pathogenesis as well as designing vaccine countermeasures to C. burnetii aerosol transmission.


Assuntos
Vacinas Bacterianas/imunologia , Coxiella burnetii/imunologia , Pulmão/microbiologia , Febre Q/veterinária , Vacinas de Produtos Inativados/imunologia , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/administração & dosagem , Modelos Animais de Doenças , Feminino , Cobaias , Pulmão/imunologia , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Febre Q/imunologia , Febre Q/prevenção & controle , Baço/imunologia , Baço/microbiologia , Vacinas de Produtos Inativados/administração & dosagem
11.
Anim Sci J ; 90(11): 1460-1467, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502390

RESUMO

Porcine edema disease (ED) is a toxemia that is caused by enteric infection with Shiga toxin 2e (Stx2e)-producing Escherichia coli (STEC) and is associated with high mortality. Since ED occurs most frequently during the weaning period, preweaning vaccination of newborn piglets is required. We developed stx2eB-transgenic lettuce as an oral vaccine candidate against ED and examined its protective efficacy using a piglet STEC infection model. Two serially developed Stx2eB-lettuce strains, 2BN containing ingredient Stx2eB constituting a concentration level of 0.53 mg Stx2eB/g of powdered lettuce dry weight (DW) and 2BH containing ingredient Stx2eB constituting a concentration level of 2.3 mg of Stx2eB/g of powdered lettuce DW, were evaluated in three sequential experiments. Taken the results together, oral administration of Stx2eB-lettuce vaccine was suggested to relieve the pathogenic symptoms of ED in piglets challenged with virulent STEC strain. Our data suggested that Stx2eB-lettuce is a promising first oral vaccine candidate against ED.


Assuntos
Animais Recém-Nascidos , Vacinas Bacterianas/administração & dosagem , Edematose Suína/etiologia , Edematose Suína/prevenção & controle , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/veterinária , Alface , Toxina Shiga II/imunologia , Escherichia coli Shiga Toxigênica , Suínos , Desmame , Administração Oral , Animais , Escherichia coli Shiga Toxigênica/patogenicidade , Virulência
12.
Lett Appl Microbiol ; 69(5): 366-372, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31508837

RESUMO

We evaluate the efficacy of recombinant DNA vaccine ABA392 against haemorrhagic septicaemia infection through intranasal administration route by targeting the mucosal immunity. The DNA vaccine was constructed and subjected to animal study using the Sprague Dawley (SD) rat. The study was divided into two major parts: (i) active and (ii) passive immunization studies, involving 30 animals for each part. Each group was then divided into five test groups: two test samples G1 and G2 with 50 and 100 µg ml-1 purified DNA vaccine; one positive control G5 with 106  CFU per ml formalin-killed PMB2; and two negative controls, G3 and G4 with normal saline and pVAX1 vector. Both studies were conducted for the determination of immunogenicity by total white blood cell count (TWBC), indirect ELISA and histopathological changes for the presence of the bronchus-associated lymphoid tissue (BALT). Our findings demonstrate that TWBC, IgA and IgG increased after each of the three vaccination regimes: groups G1, G2 and G5. Test samples G1 and G2 showed significant differences (P < 0·05) compared to the negative controls, G3 and G4, but no significant differences from the positive control G5. Groups G1, G2 and G5 showed more formation of BALT compared to the negative controls, G3 and G4. Our results show that intranasal inoculation of recombinant DNA vaccine ABA392 can provoke mucosal immunity which makes it a potential prophylactic against HS. SIGNIFICANCE AND IMPACT OF THE STUDY: New approach of combating haemorrhagic septicaemia disease among bovines by recombinant DNA vaccine is crucial to overcome the loss of edible products from the infected bovines. DNA vaccine can potentially serve as a better immunogen which would elicit both cellular and humoral immunity, and it is also stable for its molecular reproduction. This research report demonstrates an effective yet simple way of administering the DNA vaccine via the intranasal route in rats, to provoke the mucosal immunity through the development of immunoglobulins IgA, IgG and bronchus-associated lymphoid tissue which guard as the first-line defence at the host's mucosal lining.


Assuntos
Vacinas Bacterianas/administração & dosagem , Doenças dos Bovinos/prevenção & controle , Septicemia Hemorrágica/veterinária , Pasteurella multocida/imunologia , Vacinas de DNA/administração & dosagem , Administração Intranasal , Animais , Anticorpos Antibacterianos/imunologia , Vacinas Bacterianas/genética , Vacinas Bacterianas/imunologia , Bovinos , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/microbiologia , DNA Recombinante/administração & dosagem , DNA Recombinante/genética , DNA Recombinante/imunologia , Ensaio de Imunoadsorção Enzimática , Septicemia Hemorrágica/imunologia , Septicemia Hemorrágica/microbiologia , Septicemia Hemorrágica/prevenção & controle , Imunização Passiva , Masculino , Pasteurella multocida/genética , Ratos , Ratos Sprague-Dawley , Vacinas de DNA/genética , Vacinas de DNA/imunologia
13.
BMC Vet Res ; 15(1): 327, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31511007

RESUMO

BACKGROUND: Mycoplasma hyopneumoniae (M. hyopneumoniae) is the primary pathogen of porcine enzootic pneumonia, which has been associated with economic losses due to reduced daily weight gain and feed efficiency. Although it has a small genome and no more than 1000 genes, M. hyopneumoniae can be cultured in cell free media. However, some proteins were not expressed or were only expressed in negligible amounts under culture conditions. Nevertheless, some of these proteins can be expressed at a high level and induce a strong and rapid immune response after M. hyopneumoniae infection. The unexpressed or less expressed proteins may play critical roles in pathogenesis and/or immune response. In order to find the differentially expressed proteins of M. hyopneumoniae between culture condition and infected animals, we established an indirect ELISA for the detection of humoral immunodominant proteins which can discriminate between inactivated bacterin-induced hyperimmune sera and convalescent sera by using Mhp366 protein which did not react with sera from bacterin-immunized pigs, but revealed a strong immunoreaction with porcine convalescent sera. RESULTS: The checkerboard titration method was done by using porcine convalescent sera as positive sera and inactivated bacterin-induced hyperimmune sera as negative sera. The bacterial lysates of fusion proteins and free GST protein without dilution were the optimal coating antigens. The optimal blocking buffer was PBS with 10% FBS and 2.5% skimmed milk. In the checkboard ELISAs, when the sera were diluted at 1:500 and the HRP-labeled rabbit anti-pig IgG were diluted at 1:20000, most positive result was obtained for the assay. CONCLUSIONS: This established indirect ELISA can be used as a tool for the detection of humoral immunodominant proteins of M. hyopneumoniae which can discriminate between inactivated bacterin-induced hyperimmune sera and convalescent sera.


Assuntos
Vacinas Bacterianas/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Mycoplasma hyopneumoniae/imunologia , Pneumonia Suína Micoplasmática/imunologia , Animais , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Mycoplasma hyopneumoniae/química , Pneumonia Suína Micoplasmática/sangue , Suínos , Doenças dos Suínos/microbiologia
14.
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
15.
Fish Shellfish Immunol ; 94: 746-751, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31546040

RESUMO

The present study evaluated the biofilm (BF) of Vibrio anguillarum for oral vaccination of Asian seabass, Lates calcarifer. An 80-day experiment was carried out in circular fiber-reinforced plastic (FRP) tanks using free cell (FC) and BF of Vibrio anguillarum with triplicate in each. Heat-inactivated FC and BF cells at 107, 1010 and 1013 CFU/g fish/d were fed to fish for 20 days, agglutination antibody titer estimated at each 10 days interval up to 60-day post vaccination. As compared to FC and control there was a significant increase in agglutinating antibody titer in the biofilm vaccinated fishes. Among the 3 doses, BF at 1010 cfu/g fish/d was considered the ideal dose for vaccination. Relative percentage survival (RPS) was higher in biofilm vaccinated fish (85.4%) compared to that with free cells (27.0%). The study demonstrated the better performance of V. anguillarum biofilm oral vaccine compared that with free cell vaccine in L. calcarifer. The study further supports better performance of biofilm vaccine model with one more bacterial pathogen in a high carnivore fish.


Assuntos
Vacinas Bacterianas/farmacologia , Bass , Biofilmes , Doenças dos Peixes/prevenção & controle , Vacinação/veterinária , Vibrioses/veterinária , Vibrio/fisiologia , Administração Oral , Animais , Vacinas Bacterianas/administração & dosagem , Temperatura Alta , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/farmacologia , Vibrio/imunologia , Vibrioses/prevenção & controle
16.
Fish Shellfish Immunol ; 93: 631-640, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377431

RESUMO

Fish aquaculture is the world's fastest growing food production industry and infectious diseases are a major limiting factor. Vaccination is the most appropriate method for controlling infectious diseases and a key reason for the success of salmonid cultivation and has reduced the use of antibiotics. The development of fish vaccines requires the use of a great number of experimental animals that are challenged with virulent pathogens. In vitro cell culture systems have the potential to replace in vivo pathogen exposure for initial screening and testing of novel vaccine candidates/preparations, and for batch potency and safety tests. PBL contain major immune cells that enable the detection of both innate and adaptive immune responses in vitro. Fish PBL can be easily prepared using a hypotonic method and is the only way to obtain large numbers of immune cells non-lethally. Distinct gene expression profiles of innate and adaptive immunity have been observed between bacterins prepared from different bacterial species, as well as from different strains or culturing conditions of the same bacterial species. Distinct immune pathways are activated by pathogens or vaccines in vivo that can be detected in PBL in vitro. Immune gene expression in PBL after stimulation with vaccine candidates may shed light on the immune pathways involved that lead to vaccine-mediated protection. This study suggests that PBL are a suitable platform for initial screening of vaccine candidates, for evaluation of vaccine-induced immune responses, and a cheap alternative for potency testing to reduce animal use in aquaculture vaccine development.


Assuntos
Aquicultura/métodos , Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Expressão Gênica/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Oncorhynchus mykiss/genética , Oncorhynchus mykiss/imunologia , Aeromonas salmonicida/imunologia , Animais , Vacinas Bacterianas/administração & dosagem , Doenças dos Peixes/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Técnicas In Vitro/métodos , Leucócitos/imunologia , Yersinia ruckeri/imunologia
17.
J Med Microbiol ; 68(10): 1408-1418, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31418679

RESUMO

Respiratory tract infections are responsible for over 2.8 million deaths per year worldwide. Colonization is the first step in the process of microbes occupying the respiratory tract, which may lead to subsequent infection. Carriage, in contrast, is defined as the occupation of microbial species in the respiratory tract. The duration of carriage may be affected by host immunity, the composition and interactions between members of the microbial community, and the characteristics of colonizing bacteria, including physiology associated with being present in a bacterial biofilm. Numerous vaccines have been implemented to control infections caused by bacteria that can colonize and be subsequently carried. Such vaccines are often species-specific and may target a limited number of strains thereby creating a vacant niche in the upper respiratory tract. Epidemiological changes of bacteria found in both carriage and disease have therefore been widely reported, since the vacant niche is filled by other strains or species. In this review, we discuss the use of carriage-prevalence studies in vaccine evaluation and argue that such studies are essential for (1) examining the epidemiology of carriage before and after the introduction of new vaccines, (2) understanding the dynamics of the respiratory tract flora and (3) identifying the disease potential of emerging strains. In an era of increasing antibiotic resistance, bacterial carriage-prevalence studies are essential for monitoring the impact of vaccination programmes.


Assuntos
Infecções Bacterianas/microbiologia , Vacinas Bacterianas/imunologia , Portador Sadio/microbiologia , Infecções Respiratórias/microbiologia , Animais , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/imunologia , Infecções Bacterianas/prevenção & controle , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Portador Sadio/epidemiologia , Portador Sadio/imunologia , Portador Sadio/prevenção & controle , Humanos , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/prevenção & controle , Vacinação
18.
Helicobacter ; 24(5): e12652, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31414552

RESUMO

BACKGROUND: Tissue-resident memory T cells accelerate the clearance of pathogens during recall response. However, whether CD4+ TRM cells themselves can provide gastric immunity is unclear. MATERIALS AND METHODS: We established a parabiosis model between the enhanced green fluorescent protein and wild-type mice that the circulation system was shared, and the wild-type partner was vaccinated with H pylori vaccine composed of CCF and silk fibroin in gastric subserous layer to induce gastric EGFP+ CD4+ TRM cells. Antigen-specific EGFP+ CD4+ T cells and proliferous TRM cells were analyzed by flow cytometry. The colonization of H pylori was detected by quantitative real-time PCR. EGFP+ CD4+ TRM cells and the inflammation of the stomach were observed by histology. RESULTS: A parabiosis animal model was employed to identify the cells that introduced by vaccination in GSL. Antigen-specific EGFP+ CD4+ T cells could be detected at day 7 post-vaccination. Thirty days later, EGFP+ CD4+ TRM cells were established with a phenotype of CD69+ CD103- . Of note, we found that when circulating lymphocytes were depleted by FTY720 administration, these TRM cells could proliferate in situ and differentiate into effector Th1 cells after H pylori challenge. A decrease in H pylori colonization was observed in the vaccinated mice but not unvaccinated mice. Further, we found that although FTY720 was administrated, mounted pro-inflammatory myeloid cells still emerged in the stomach of the vaccinated mice, which might contribute to the reduction of H pylori colonization. CONCLUSIONS: Our study reveals that H pylori vaccine-induced CD4+ TRM cells can proliferate and differentiate in situ to enhance gastric local immunity during recall response.


Assuntos
Vacinas Bacterianas/imunologia , Linfócitos T CD4-Positivos/imunologia , Mucosa Gástrica/imunologia , Infecções por Helicobacter/prevenção & controle , Helicobacter pylori/imunologia , Memória Imunológica , Animais , Vacinas Bacterianas/administração & dosagem , Proliferação de Células , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Camundongos Endogâmicos C57BL , Subpopulações de Linfócitos T/imunologia
19.
PLoS Negl Trop Dis ; 13(8): e0007644, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31430284

RESUMO

Bacillus anthracis and Yersinia pestis are zoonotic bacteria capable of causing severe and sometimes fatal infections in animals and humans. Although considered as diseases of antiquity in industrialized countries due to animal and public health improvements, they remain endemic in vast regions of the world disproportionally affecting the poor. These pathogens also remain a serious threat if deployed in biological warfare. A single vaccine capable of stimulating rapid protection against both pathogens would be an extremely advantageous public health tool. We produced multiple-antigen fusion proteins (MaF1 and MaF2) containing protective regions from B. anthracis protective antigen (PA) and lethal factor (LF), and from Y. pestis V antigen (LcrV) and fraction 1 (F1) capsule. The MaF2 sequence was also expressed from a plasmid construct (pDNA-MaF2). Immunogenicity and protective efficacy were investigated in mice following homologous and heterologous prime-boost immunization. Antibody responses were determined by ELISA and anthrax toxin neutralization assay. Vaccine efficacy was determined against lethal challenge with either anthrax toxin or Y. pestis. Both constructs elicited LcrV and LF-specific serum IgG, and MaF2 elicited toxin-neutralizing antibodies. Immunizations with MaF2 conferred 100% and 88% protection against Y. pestis and anthrax toxin, respectively. In contrast, pDNA-MaF2 conferred only 63% protection against Y. pestis and no protection against anthrax toxin challenge. pDNA-MaF2-prime MaF2-boost induced 75% protection against Y. pestis and 25% protection against anthrax toxin. Protection was increased by the molecular adjuvant CARDif. In conclusion, MaF2 is a promising multi-antigen vaccine candidate against anthrax and plague that warrants further investigation.


Assuntos
Antraz/prevenção & controle , Antígenos de Bactérias/imunologia , Bacillus anthracis/imunologia , Vacinas Bacterianas/imunologia , Peste/prevenção & controle , Proteínas Recombinantes de Fusão/imunologia , Yersinia pestis/imunologia , Animais , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/genética , Bacillus anthracis/genética , Toxinas Bacterianas/genética , Toxinas Bacterianas/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/genética , Vacinas Bacterianas/isolamento & purificação , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos BALB C , Proteínas Citotóxicas Formadoras de Poros/genética , Proteínas Citotóxicas Formadoras de Poros/imunologia , Proteínas Recombinantes de Fusão/genética , Análise de Sobrevida , Resultado do Tratamento , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/isolamento & purificação , Yersinia pestis/genética
20.
J Dairy Sci ; 102(10): 9328-9344, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31400892

RESUMO

Our objective was to evaluate the efficacy of a vaccine against staphylococcal mastitis in 5 dairy sheep farms, with 316 ewes in the vaccinated (V) group and 307 in the control (C) group studied throughout a lactation period. Two administrations of the vaccine were performed during the last stage of gestation of ewes. Starting 15 d after lambing and at monthly intervals thereafter, up to 9 milk samplings were performed for bacteriological and cytological examinations. Staphylococcal isolates recovered were examined for biofilm formation. Blood samples were collected for measurement of IgG poly-N-acetylglucosamine-specific antibodies. The most frequently isolated bacteria were staphylococci: 56.4 and 76.1%, respectively, of total isolates recovered from ewes of group V and C, respectively; staphylococci as causal agents of mastitis were isolated less frequently from V (5.3%) than in ewes in C (10.3%). Among mastitis-associated staphylococcal isolates recovered from V ewes, a smaller proportion was biofilm-forming than among ones from C: 53.2% versus 74.9% of isolates; biofilm-forming staphylococci as causal agents of mastitis were isolated less frequently from ewes in group V (2.3%) than in ewes in group C (6.0%). Anti-poly-N-acetylglucosamine-specific antibody values increased in V ewes and were higher than in C; a greater proportion of ewes with low antibody titers developed staphylococcal mastitis (41.4%) than of V ewes with high antibody titers (17.0%). Incidence risk of mastitis, staphylococcal mastitis, and biofilm-associated staphylococcal mastitis was smaller in V than in C: 36.7, 17.1, and 8.0% versus 44.3, 30.9, and 18.9%, respectively. The first case of staphylococcal mastitis occurred later in V than in C: third versus second sampling point. Overall, efficacy of the vaccine was 44.6% for staphylococcal mastitis, 57.7% for biofilm-associated staphylococcal mastitis, 33.1% for staphylococcal intramammary infection, and 51.5% for biofilm-associated staphylococcal intramammary infection. Nevertheless, vaccination should not be the only means for controlling mastitis; other udder health management measures should be included therein to improve control of the infection.


Assuntos
Vacinas Bacterianas/administração & dosagem , Biofilmes , Mastite/veterinária , Doenças dos Ovinos/prevenção & controle , Infecções Estafilocócicas/veterinária , Animais , Feminino , Incidência , Lactação , Glândulas Mamárias Animais/microbiologia , Mastite/prevenção & controle , Leite/microbiologia , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/microbiologia , Infecções Estafilocócicas/prevenção & controle
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