RESUMEN
BACKGROUND: Klebsiella pneumoniae (KP), responsible for acute lung injury (ALI) and inflammation of the gastrointestinal tract, is a zoonotic pathogen that poses a threat to livestock farming worldwide. Nevertheless, there is currently no validated vaccine to prevent KP infection. The development of mucosal vaccines against KP using Lactobacillus plantarum (L. plantarum) is an effective strategy. RESULTS: Firstly, the L. plantarum strains NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c were constructed via homologous recombination to express the aCD11c protein either inducibly or constitutively. Both NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c strains could enhance the adhesion and invasion of L. plantarum on bone marrow-derived dendritic cells (BMDCs), and stimulate the activation of BMDCs compared to the control strain NC8-pSIP409 in vitro. Following oral immunization of mice with NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c, the cellular, humoral, and mucosal immunity were significantly improved, as evidenced by the increased expression of CD4+ IL-4+ T cells in the spleen, IgG in serum, and secretory IgA (sIgA) in the intestinal lavage fluid (ILF). Furthermore, the protective effects of L. plantarum against inflammatory damage caused by KP infection were confirmed by assessing the bacterial loads in various tissues, lung wet/dry ratio (W/D), levels of inflammatory cytokines, and histological evaluation, which influenced T helper 17 (Th17) and regulatory T (Treg) cells in peripheral blood and lung. CONCLUSIONS: Both the inducible and constitutive L. plantarum strains NC8-pSIP409-aCD11c' and NC8-pLc23-aCD11c have been found to stimulate cellular and humoral immunity levels and alleviate the inflammatory response caused by KP infection. These findings have provided a basis for the development of a novel vaccine against KP.
Asunto(s)
Inmunidad Celular , Infecciones por Klebsiella , Klebsiella pneumoniae , Lactobacillus plantarum , Animales , Infecciones por Klebsiella/prevención & control , Infecciones por Klebsiella/veterinaria , Infecciones por Klebsiella/inmunología , Klebsiella pneumoniae/inmunología , Ratones , Administración Oral , Femenino , Ratones Endogámicos BALB C , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Células Dendríticas/inmunología , InflamaciónRESUMEN
Background: Pneumonia is the largest cause of mortality in Canadian lambs. Currently there are no licensed ovine vaccines in Canada to reduce economic losses from this production-limiting disease. Objective animals and procedure: The effectiveness of an experimental subunit Mannheimia haemolytica leukotoxin A (LtxA) and transferrin binding protein B (TbpB) vaccine was evaluated in lambs for reduction of clinical disease in an experimental challenge study and in a controlled randomized field trial in a large commercial sheep operation. Results: Following an experimental challenge of parainfluenza 3 virus and M. haemolytica, the subunit vaccine induced significantly higher LtxA and TbpB antibody titers at 48 d post-challenge compared to the adjuvant and Ovipast Plus bacterin (Merck Animal Health), but there were no significant differences in clinical signs or mortality among vaccine groups. Following vaccination of commercial ewes and their lambs at weaning, the only significant difference in health, growth, and carcass traits between vaccinates and non-vaccinates was a slightly higher pneumonia treatment rate in vaccinated preweaned lambs (25.7%) compared to unvaccinated preweaned lambs (23.4%) (P = 0.04). Conclusion and clinical relevance: Although vaccination with the experimental subunit M. haemolytica vaccine induced high LtxA and TbpB antibodies, it did not reduce clinical disease in lambs following an experimental challenge study or in a controlled randomized field trial in a commercial sheep operation. Further research is required to identify additional protective antigens for a safe and effective ovine respiratory vaccine to reduce pneumonia losses in commercial sheep flocks.
Efficacité d'un vaccin respiratoire sous-unitaire expérimental de Mannheimia haemolytica ovin à réduire la pneumonie chez les agneaux. Contexte: La pneumonie est la principale cause de mortalité chez les agneaux canadiens. Présentement, il n'y a aucun vaccin ovin homologué au Canada pour réduire les pertes économiques associées à cette pathologie limitant la production. Objectif animaux et procédure: L'efficacité d'un vaccin sous-unitaire expérimental à base de la leucotoxine A (LtxA) et de la protéine B liant la transferrine (TbpB) de Mannheimia haemolytica a été évalué chez des agneaux pour la réduction de la maladie clinique lors d'une infection expérimentale et lors d'un essai de champs randomisé et contrôlé dans un grand élevage commercial de moutons. Résultats: À la suite d'une infection expérimentale avec le virus parainfluenza 3 et M. haemolytica, le vaccin sous-unitaire a induit des titres d'anticorps significativement plus élevés contre LtxA et TbpB à 48 j post-infection comparativement à l'adjuvant et à la bactérine Ovipast Plus (Merck Santé Animale), mais il n'y avait aucune différence significative dans les signes cliniques ou la mortalité parmi les groupes vaccinés. À la suite de la vaccination de brebis commerciales et de leurs agneaux au moment du sevrage, la seule différence significative dans la santé, la croissance et les caractéristiques des carcasses entre les animaux vaccinés et non-vaccinés était un taux légèrement plus élevé de traitement de la pneumonie chez les agneaux vaccinés pré-sevrage (25,7 %) comparativement aux agneaux non-vaccinés au présevrage (23,4 %) (P = 0,04). Conclusion et pertinence clinique: Bien que la vaccination avec le vaccin sous-unitaire expérimental M. haemolytica ait induit des taux d'anticorps élevés contre LtxA et TbpB, il n'a pas réduit la maladie clinique chez les agneaux à la suite d'une infection expérimentale ou lors d'un essai clinique randomisé contrôlé dans un élevage ovin commercial. Des recherches supplémentaires sont requises pour identifier des antigènes protecteurs additionnels pour un vaccin respiratoire ovin efficace pour réduire les pertes associées à la pneumonie dans les troupeaux ovins commerciaux.(Traduit par Dr Serge Messier).
Asunto(s)
Vacunas Bacterianas , Mannheimia haemolytica , Enfermedades de las Ovejas , Vacunas de Subunidad , Animales , Mannheimia haemolytica/inmunología , Ovinos , Enfermedades de las Ovejas/prevención & control , Vacunas Bacterianas/inmunología , Femenino , Vacunas de Subunidad/inmunología , Neumonía/veterinaria , Neumonía/prevención & control , Masculino , Anticuerpos Antibacterianos/sangre , Pasteurelosis Neumónica/prevención & control , Pasteurelosis Neumónica/inmunologíaRESUMEN
INTRODUCTION: Clostridioides difficile (C.diff) infection (CDI) causes significant morbidity and mortality among older adults. Vaccines to prevent CDI are in development; however, data on the target population's preferences are needed to inform vaccination recommendations in the United States (US). This study assessed US adults' willingness to receive a C.diff vaccine and examined how vaccine attributes influence their choices. METHODS: A cross-sectional online survey with a discrete choice experiment (DCE) was conducted among US adults aged ≥50 years. DCE attributes included effectiveness, duration of protection, reduction in symptom severity, out-of-pocket (OOP) costs, number of doses, and side effects. The DCE included 11 choice tasks, each with two hypothetical vaccine profiles and an opt-out (i.e., no vaccine). Attribute-level preference weights were estimated using hierarchical Bayesian modeling. Attribute relative importance (RI) was compared between select subgroups. RESULTS: Of 1216 adults in the analyses, 29.9% reported they knew either 'a little' (20.7%) or 'a lot' (9.2%) about C.diff before the study. A C.diff vaccine was chosen 58.0% of the time (vs. opt-out) across choice tasks. It was estimated that up to 75.0% would choose a vaccine when OOP was $0. Those who were immunocompromised/high-risk for CDI (vs. not) more frequently chose a C.diff vaccine. Decreases in OOP costs (RI = 56.1), improvements in vaccine effectiveness (RI = 17.7), and reduction in symptom severity (RI = 10.3) were most important to vaccine choice. The rank ordering of attributes by importance was consistent across subgroups. CONCLUSION: OOP cost, improvements in vaccine effectiveness, and reduction in CDI severity were highly influential to vaccine selection. Most adults aged ≥50 years were receptive to a C.diff vaccine, especially with little-to-no OOP cost, suggesting that mandating insurance coverage of vaccination with no copayment may increase uptake. The limited awareness about C.diff among adults presents an opportunity for healthcare providers to educate their patients about CDI prevention.
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Vacunas Bacterianas , Clostridioides difficile , Infecciones por Clostridium , Humanos , Persona de Mediana Edad , Femenino , Estados Unidos , Masculino , Infecciones por Clostridium/prevención & control , Estudios Transversales , Anciano , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/economía , Clostridioides difficile/inmunología , Vacunación/psicología , Prioridad del Paciente/estadística & datos numéricos , Encuestas y Cuestionarios , Anciano de 80 o más Años , Teorema de BayesRESUMEN
Aeromonas veronii is an opportunistic pathogen that poses great threat to aquaculture and human health, so there is an urgent need for green and efficient methods to deal with its infection. In this study, single and double gene deletion strains (AV-ΔaroA, AV-Δppk1 and AV-ΔaroA/ppk1) that can be stably inherited were constructed. Pathogenicity test showed that the toxicity of AV-ΔaroA and AV-ΔaroA/ppk1 was significantly lower compared to wild-type A. veronii. Biological characterization analysis revealed that the decrease in pathogenicity might be due to the declined growth, motility, biofilm formation abilities and the expression of virulence-related genes in mutants. Subsequently, we evaluated the efficacy of AV-ΔaroA/ppk1 as a live attenuated vaccine (LAV). Safety assessment experiments showed that AV-ΔaroA/ppk1 injected at a concentration of 3 × 107 CFU/mL was safe for C. carassius. The relative percentage survival of AV-ΔaroA/ppk1 was 67.85 %, significantly higher than that of the inactivated A. veronii, which had an RPS of 54.84 %. This improved protective effect was mainly attributed to the increased levels of A. veronii specific IgM antibody, enhanced alkaline phosphatase, lysozyme and superoxide dismutase activities, as well as higher expression levels of several immune related genes. Together, these findings deepen our understanding of the functional roles of aroA and ppk1 in A. veronii pathogenicity, provide a good candidate of LAV for A. veronii.
Asunto(s)
Aeromonas veronii , Vacunas Bacterianas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Vacunas Atenuadas , Aeromonas veronii/patogenicidad , Aeromonas veronii/fisiología , Aeromonas veronii/inmunología , Vacunas Atenuadas/inmunología , Vacunas Bacterianas/inmunología , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/inmunología , Infecciones por Bacterias Gramnegativas/prevención & control , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/inmunología , Enfermedades de los Peces/microbiología , Animales , Virulencia , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Carpas/inmunología , Eliminación de GenRESUMEN
Syphilis, caused by Treponema pallidum subsp. pallidum, is a global health concern with increasing rates worldwide. Current prevention strategies, including screen-and-treat approaches, are not sufficient to resolve rising infection rates, emphasizing the need for a vaccine. Developing a syphilis vaccine necessitates a range of cross-disciplinary considerations, including essential disease-specific protection, technical requirements, economic feasibility, manufacturing constraints, public acceptance, equitable vaccine access, alignment with global public vaccination programs, and identification of essential populations to be vaccinated to achieve herd immunity. Central to syphilis vaccine development is prioritization of global vaccine availability, including access in low- to middle-income settings. Various vaccine platforms, including subunit, virus-like particle (VLP), mRNA, and outer membrane vesicle (OMV) vaccines, present both advantages and challenges. The proactive consideration of both manufacturing feasibility and efficacy throughout the pre-clinical research and development stages is essential for producing an efficacious, inexpensive, and scalable syphilis vaccine to address the growing global health burden caused by this disease.
Asunto(s)
Vacunas Bacterianas , Sífilis , Treponema pallidum , Desarrollo de Vacunas , Sífilis/prevención & control , Sífilis/inmunología , Humanos , Treponema pallidum/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Salud Global , Animales , Vacunas de Partículas Similares a Virus/inmunologíaRESUMEN
Bacterial septicemia represents a significant disease affecting cultured grass carp culture, with the primary etiological agent identified as the Gram-negative bacterium Aeromonas veronii. In response to an outbreak of septicemia in Guangzhou, we developed a formaldehyde-inactivated vaccine against an A. veronii strain designated AV-GZ21-2. This strain exhibited high pathogenicity in experimental infections across at all developmental stages of grass carp. Mortality rates for grass carp weighing 15 ± 5 g ranged from 16 % to 92 % at exposure temperatures of 19 °C-34 °C, respectively. The median lethal dose (LD50) for grass carp groups weighing 15 ± 5 g, 60 ± 10 g, 150 ± 30 g and 500 ± 50 g were determined to be 1.43, 2.52, 4.65 and 7.12 × 107(CFU/mL), respectively. We investigated the inactivated vaccine in conbination with aluminum hydroxide gel (AV-AHG), Montanide ISA201VG (AV-201VG), and white oil (AV-WO) adjuvants. This study aimed to optimize inactivation conditions and identify the adjuvant that elicits the most robust immune response. The AV-GZ21-2 inactivated bacterial solution (AV),when combined with various adjuvants, was capable of inducing a strong specific immune response in grass carp. The relative percent survival (RPS) following a lethal challenge with AV-GZ21-2 were 94 % for AV-AHG, 88 % for AV-201VG, 84 % for AV-WO and 78 % for AV alone. The minimum immunization dose of the AV-AHG vaccine was determined to be 6.0 × 107 CFU per fish, providing immunity for a duration of six months with an immune protection level exceeding 75 %. Furthermore, the AV-AHG vaccine demonstrated significant protective efficacy against various epidemic isolates of A. veronii. Consequently, we developed an inactivated vaccine targeting a highly pathogenic strain of A. veronii, incorporating an aluminum hydroxide gel adjuvant, which resulted in high immune protection and a duration of immunity exceeding six months. These findings suggest that the AV-AHG vaccine holds substantial potential for industrial application.
Asunto(s)
Adyuvantes Inmunológicos , Aeromonas veronii , Vacunas Bacterianas , Carpas , Enfermedades de los Peces , Infecciones por Bacterias Gramnegativas , Vacunas de Productos Inactivados , Animales , Carpas/microbiología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Vacunas de Productos Inactivados/administración & dosificación , Aeromonas veronii/inmunología , Enfermedades de los Peces/prevención & control , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/inmunología , Infecciones por Bacterias Gramnegativas/prevención & control , Infecciones por Bacterias Gramnegativas/veterinaria , Infecciones por Bacterias Gramnegativas/inmunología , Virulencia , Adyuvantes Inmunológicos/administración & dosificación , Dosificación Letal Mediana , Temperatura , China/epidemiología , Hidróxido de Aluminio/administración & dosificaciónRESUMEN
Helicobacter pylori (H. pylori) is an infectious bacterium that colonizes the stomach of approximately half of the global population. It has been classified as a Group I carcinogen by the World Health Organization due to its strong association with an increased incidence of gastric cancer and exacerbation of stomach diseases. The primary treatment for H. pylori infection currently involves triple or quadruple therapy, primarily consisting of antibiotics and proton pump inhibitors. However, the increasing prevalence of antibiotic resistance poses significant challenges to this approach, underscoring the urgent need for an effective vaccine. In this study, a novel multi-epitope H. pylori vaccine was designed using immunoinformatics. The vaccine contains epitopes derived from nine essential proteins. Software tools and online servers were utilized to predict, evaluate, and analyze the physiochemical properties, secondary and tertiary structures, and immunogenicity of the candidate vaccine. These comprehensive assessments ultimately led to the formulation of an optimal design scheme for the vaccine. Through constructing a novel multi-epitope vaccine based on immunoinformatics, this study offers promising prospects and great potential for the prevention of H. pylori infection. This study also provides a reference strategy to develop multi-epitope vaccines for other pathogens.
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Vacunas Bacterianas , Biología Computacional , Infecciones por Helicobacter , Helicobacter pylori , Helicobacter pylori/inmunología , Vacunas Bacterianas/inmunología , Biología Computacional/métodos , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/prevención & control , Humanos , Antígenos Bacterianos/inmunología , Epítopos/inmunología , Desarrollo de Vacunas , InmunoinformáticaRESUMEN
The increasing and ongoing issue of antibiotic resistance in bacteria is of huge concern globally, mainly to healthcare facilities. It is now crucial to develop a vaccine for therapeutic and preventive purposes against the bacterial species causing hospital-based infections. Among the many antibiotic- resistant bacterial pathogens, the Enterobacter cloacae complex (ECC) including six species, E. Colcae, E. absuriae, E. kobie, E. hormaechei, E. ludwigii, and E. nimipressuralis, are dangerous to public health and may worsen the situation. Vaccination plays a vital role in the prevention of infections and infectious diseases. This research highlighted the construction and design of a multi-epitope vaccine for the E. cloacae complex by retrieving their complete sequenced proteome. The retrieved proteome was assessed to opt for potential vaccine candidates using immunoinformatic tools. Both B and T-cell epitopes were predicted in order to create both humoral and cellular immunity and further scrutinized for antigenicity, allergenicity, water solubility, and toxicity analysis. The final potential epitopes were subjected to population coverage analysis. Major histocompatibility complex (MHC) class combined, and MHC Class I and II world population coverage was obtained as 99.74%, and 98.55% respectively while a combined 81.81% was covered. A multi-epitope peptide-based vaccine construct consisting of the adjuvant, epitopes, and linkers was subjected to the ProtParam tool to calculate its physiochemical properties. The total amino acids were 236, the molecular weight was 27.64kd, and the vaccine construct was stable with an instability index of 27.01. The Grand Average of Hydropathy (GRAVY) (hydrophilicity) value obtained was -0.659, being more negative and depicting the hydrophilic character. It was non-allergen antigenic with an antigenicity of 0.8913. The vaccine construct was further validated for binding efficacy with immune cell receptors MHC-I, MHC-II, and Toll-like receptor (TLR)-4. The molecular docking results depict that the designed vaccine has good binding potency with immune receptors crucial for antigen presentation and processing. Among the Vaccine-MHC-I, Vaccine-MHC-II, and Vaccine-TLR-4 complexes, the best-docked poses were identified based on their lowest binding energy scores of -886.8, -995.6, and -883.6, respectively. Overall, we observed that the designed vaccine construct can evoke a proper immune response and the construct could help experimental researchers in the formulation of a vaccine against the targeted pathogens.
Asunto(s)
Vacunas Bacterianas , Enterobacter cloacae , Epítopos de Linfocito B , Epítopos de Linfocito T , Enterobacter cloacae/inmunología , Humanos , Vacunas Bacterianas/inmunología , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/química , Epítopos de Linfocito B/inmunología , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/prevención & control , Biología Computacional/métodos , Simulación del Acoplamiento Molecular , Desarrollo de Vacunas , Vacunología/métodos , Modelos MolecularesRESUMEN
The ESKAPE family, comprising Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp., poses a significant global threat due to their heightened virulence and extensive antibiotic resistance. These pathogens contribute largely to the prevalence of nosocomial or hospital-acquired infections, resulting in high morbidity and mortality rates. To tackle this healthcare problem urgent measures are needed, including development of innovative vaccines and therapeutic strategies. Designing vaccines involves a complex and resource-intensive process of identifying protective antigens and potential vaccine candidates (PVCs) from pathogens. Reverse vaccinology (RV), an approach based on genomics, made this process more efficient by leveraging bioinformatics tools to identify potential vaccine candidates. In recent years, artificial intelligence and machine learning (ML) techniques has shown promise in enhancing the accuracy and efficiency of reverse vaccinology. This study introduces a supervised ML classification framework, to predict potential vaccine candidates specifically against ESKAPE pathogens. The model's training utilized biological and physicochemical properties from a dataset containing protective antigens and non-protective proteins of ESKAPE pathogens. Conventional autoencoders based strategy was employed for feature encoding and selection. During the training process, seven machine learning algorithms were trained and subjected to Stratified 5-fold Cross Validation. Random Forest and Logistic Regression exhibited best performance in various metrics including accuracy, precision, recall, WF1 score, and Area under the curve. An ensemble model was developed, to take collective strengths of both the algorithms. To assess efficacy of our final ensemble model, a high-quality benchmark dataset was employed. VacSol-ML(ESKAPE) demonstrated outstanding discrimination between protective vaccine candidates (PVCs) and non-protective antigens. VacSol-ML(ESKAPE), proves to be an invaluable tool in expediting vaccine development for these pathogens. Accessible to the public through both a web server and standalone version, it encourages collaborative research. The web-based and standalone tools are available at http://vacsolml.mgbio.tech/.
Asunto(s)
Antígenos Bacterianos , Vacunas Bacterianas , Aprendizaje Automático , Antígenos Bacterianos/inmunología , Humanos , Vacunas Bacterianas/inmunología , Klebsiella pneumoniae/inmunología , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidad , Enterococcus faecium/inmunología , Enterococcus faecium/genética , Staphylococcus aureus/inmunología , Staphylococcus aureus/genética , Acinetobacter baumannii/inmunología , Pseudomonas aeruginosa/inmunología , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidad , Biología Computacional/métodos , Enterobacter/inmunología , Enterobacter/genética , Vacunología/métodosRESUMEN
Helicobacter pylori (H. pylori) is responsible for various chronic or acute diseases, such as stomach ulcers, dyspepsia, peptic ulcers, gastroesophageal reflux, gastritis, lymphoma, and stomach cancers. Although specific drugs are available to treat the bacterium's harmful effects, there is an urgent need to develop a preventive or therapeutic vaccine. Therefore, the current study aims to create a multi-epitope vaccine against H. pylori using lipid nanoparticles. Five epitopes from five target proteins of H. pylori, namely, Urease, CagA, HopE, SabA, and BabA, were used. Immunogenicity, MHC (Major Histocompatibility Complex) bonding, allergenicity, toxicity, physicochemical analysis, and global population coverage of the entire epitopes and final construct were carefully examined. The study involved using various bioinformatic web tools to accomplish the following tasks: modeling the three-dimensional structure of a set of epitopes and the final construct and docking them with Toll-Like Receptor 4 (TLR4). In the experimental phase, the final multi-epitope construct was synthesized using the solid phase method, and it was then enclosed in lipid nanoparticles. After synthesizing the construct, its loading, average size distribution, and nanoliposome shape were checked using Nanodrop at 280 nm, dynamic light scattering (DLS), and atomic force microscope (AFM). The designed vaccine has been confirmed to be non-toxic and anti-allergic. It can bind with different MHC alleles at a rate of 99.05%. The construct loading was determined to be about 91%, with an average size of 54 nm. Spherical shapes were also observed in the AFM images. Further laboratory tests are necessary to confirm the safety and immunogenicity of the multi-epitope vaccine.
Asunto(s)
Vacunas Bacterianas , Biología Computacional , Helicobacter pylori , Nanopartículas , Helicobacter pylori/inmunología , Nanopartículas/química , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/química , Biología Computacional/métodos , Humanos , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/química , Epítopos/inmunología , Epítopos/química , Simulación del Acoplamiento Molecular , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/química , Infecciones por Helicobacter/prevención & control , Infecciones por Helicobacter/inmunología , Receptor Toll-Like 4/inmunología , Ureasa/inmunología , Ureasa/química , Inmunoinformática , LiposomasRESUMEN
Analysis of the recall response ex vivo in cattle vaccinated with a Mycobacterium avium subsp. paratuberculosis (Map) rel deletion mutant revealed the immune response was directed toward a 35 kD major membrane protein (MMP) of Map. Antigen presenting cells (APC) primed with MMP elicited expansion of CD8 cytotoxic memory T cells (CTL) with ability to kill intracellular bacteria. Development of CTL was MHC-restricted. The gene MAP2121c, encoding MMP, was modified for expression of MMP (tPA-MMP-2mut) in a mammalian cell line to explore the potential of developing MMP as a vaccine. Ex vivo stimulation of PBMC, from Map free cattle, with APC primed with tPA-MMP-2mut expressed p35 elicited a primary CD8 CTL response comparable to the recall response elicited with PBMC from cattle vaccinated with either the Maprel deletion mutant or MMP. In the present study, the modified gene for MMP, now referred to as p35NN, was placed into a bovine herpes virus-4 (BoHV4) vector to determine the potential use of BoHV-4AΔTK-p35NN as a peptide-based vaccine. Subcutaneous vaccination of healthy cattle with BoHV-4AΔTK-p35NN elicited a CTL recall response, as detected ex vivo. The results show use of a virus vector is an effective way for delivery of MMP as a vaccine. The immunogenic activity of MMP was not lost when modified for expression in mammalian cells. The next step is to conduct a field trial to determine if presence of an immune response to MMP prevents Map from establishing an infection.
Asunto(s)
Vacunas Bacterianas , Enfermedades de los Bovinos , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis , Linfocitos T Citotóxicos , Animales , Bovinos , Mycobacterium avium subsp. paratuberculosis/inmunología , Paratuberculosis/inmunología , Paratuberculosis/prevención & control , Vacunas Bacterianas/inmunología , Enfermedades de los Bovinos/inmunología , Enfermedades de los Bovinos/prevención & control , Enfermedades de los Bovinos/microbiología , Linfocitos T Citotóxicos/inmunología , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/genética , Vacunación/veterinaria , Vectores Genéticos/inmunología , Linfocitos T CD8-positivos/inmunología , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genéticaRESUMEN
Pseudomonas aeruginosa is a complex nosocomial infectious agent responsible for numerous illnesses, with its growing resistance variations complicating treatment development. Studies have emphasized the importance of virulence factors OprE and OprF in pathogenesis, highlighting their potential as vaccine candidates. In this study, B-cell, MHC-I, and MHC-II epitopes were identified, and molecular linkers were active to join these epitopes with an appropriate adjuvant to construct a vaccine. Computational tools were employed to forecast the tertiary framework, characteristics, and also to confirm the vaccine's composition. The potency was weighed through population coverage analysis and immune simulation. This project aims to create a multi-epitope vaccine to reduce P. aeruginosa-related illness and mortality using immunoinformatics resources. The ultimate complex has been determined to be stable, soluble, antigenic, and non-allergenic upon inspection of its physicochemical and immunological properties. Additionally, the protein exhibited acidic and hydrophilic characteristics. The Ramachandran plot, ProSA-web, ERRAT, and Verify3D were employed to ensure the final model's authenticity once the protein's three-dimensional structure had been established and refined. The vaccine model showed a significant binding score and stability when interacting with MHC receptors. Population coverage analysis indicated a global coverage rate of 83.40%, with the USA having the highest coverage rate, exceeding 90%. Moreover, the vaccine sequence underwent codon optimization before being cloned into the Escherichia coli plasmid vector pET-28a (+) at the EcoRI and EcoRV restriction sites. Our research has developed a vaccine against P. aeruginosa that has strong binding affinity and worldwide coverage, offering an acceptable way to mitigate nosocomial infections.
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Biología Computacional , Infecciones por Pseudomonas , Pseudomonas aeruginosa , Sepsis , Pseudomonas aeruginosa/inmunología , Pseudomonas aeruginosa/genética , Humanos , Infecciones por Pseudomonas/prevención & control , Infecciones por Pseudomonas/inmunología , Infecciones por Pseudomonas/microbiología , Sepsis/prevención & control , Sepsis/inmunología , Sepsis/microbiología , Biología Computacional/métodos , Epítopos/inmunología , Epítopos/química , Neumonía/prevención & control , Neumonía/inmunología , Neumonía/microbiología , Vacunas contra la Infección por Pseudomonas/inmunología , Vacunas Bacterianas/inmunología , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genéticaRESUMEN
Lyme disease is caused by the spirochete, Borrelia burgdorferi, which is transmitted by Ixodes spp ticks. The rise in Lyme disease cases since its discovery in the 1970s has reinforced the need for a vaccine. A vaccine based on B burgdorferi outer surface protein A (OspA) was approved by the Food and Drug Administration (FDA) several decades ago, but was pulled from the market a few years later, reportedly due to poor sales, despite multiple organizations concluding that it was safe and effective. Newer OspA-based vaccines are being developed and are likely to be available in the coming years. More recently, there has been a push to develop vaccines that target the tick vector instead of the pathogen to inhibit tick feeding and thus prevent transmission of tick-borne pathogens to humans and wildlife reservoirs. This review outlines the history of Lyme disease vaccines and this movement to anti-tick vaccine approaches.
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Borrelia burgdorferi , Ixodes , Vacunas contra Enfermedad de Lyme , Enfermedad de Lyme , Enfermedad de Lyme/prevención & control , Enfermedad de Lyme/inmunología , Humanos , Animales , Borrelia burgdorferi/inmunología , Vacunas contra Enfermedad de Lyme/inmunología , Ixodes/microbiología , Vacunación , Proteínas de la Membrana Bacteriana Externa/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Antígenos de Superficie/inmunología , Lipoproteínas/inmunologíaRESUMEN
Klebsiella pneumoniae is a primary cause of clinical mastitis in dairy cows, with prevention being crucial, as treatments often fail due to antimicrobial resistance. Recent studies identified type I fimbrial antigens of K. pneumoniae as promising vaccine candidates, but there are limited research data. In this study, 3 fimbriae genes (fimA, fimC and fimG) were cloned and recombinantly expressed in Escherichia coli and their protective efficacy against K. pneumoniae evaluated in a mouse model. All 3 recombinant fimbriae proteins elicited strong humoral immune responses in mice, significantly increasing IgG, IgG1 and IgG2a. Notably, using a model of mice challenged with an intraperitoneal injection of bacteria, FimG significantly reduced bacterial loads in the spleen and lung, whereas FimA and FimC had limited protection for these organs. Either active or passive immunization with FimG produced substantial protective effects in mice challenged with K. pneumoniae LD100; in contrast, the mortality rate in the FimA-immunized group was similar to that of the control group, whereas FimC had weak protection. We concluded that the FimG recombinant protein vaccine had a favorable protective effect, with potential for immunization against K. pneumoniae mastitis.
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Anticuerpos Antibacterianos , Vacunas Bacterianas , Modelos Animales de Enfermedad , Proteínas Fimbrias , Infecciones por Klebsiella , Klebsiella pneumoniae , Ratones Endogámicos BALB C , Animales , Klebsiella pneumoniae/inmunología , Ratones , Infecciones por Klebsiella/prevención & control , Infecciones por Klebsiella/inmunología , Infecciones por Klebsiella/microbiología , Proteínas Fimbrias/inmunología , Proteínas Fimbrias/genética , Femenino , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Proteínas Recombinantes/inmunología , Fimbrias Bacterianas/inmunología , Inmunoglobulina G/sangre , Inmunidad HumoralRESUMEN
Mycoplasma pulmonis (M. pulmonis) is an emerging respiratory infection commonly linked to prostate cancer, and it is classified under the group of mycoplasmas. Improved management of mycoplasma infections is essential due to the frequent ineffectiveness of current antibiotic treatments in completely eliminating these pathogens from the host. The objective of this study is to design and construct effective and protective vaccines guided by structural proteomics and machine learning algorithms to provide protection against the M. pulmonis infection. Through a thorough examination of the entire proteome of M. pulmonis, four specific targets Membrane protein P80, Lipoprotein, Uncharacterized protein and GGDEF domain-containing protein have been identified as appropriate for designing a vaccine. The proteins underwent mapping of cytotoxic T lymphocyte (CTL), helper T lymphocyte (HTL) (IFN)-γ ±, and B-cell epitopes using artificial and recurrent neural networks. The design involved the creation of mRNA and peptide-based vaccine, which consisted of 8 CTL epitopes associated by GGS linkers, 7 HTL (IFN-positive) epitopes, and 8 B-cell epitopes joined by GPGPG linkers. The vaccine designed exhibit antigenic behavior, non-allergenic qualities, and exceptional physicochemical attributes. Structural modeling revealed that correct folding is crucial for optimal functioning. The coupling of the MEVC and Toll-like Receptors (TLR)1, TLR2, and TLR6 was examined through molecular docking experiments. This was followed by molecular simulation investigations, which included binding free energy estimations. The results indicated that the dynamics of the interaction were stable, and the binding was strong. In silico cloning and optimization analysis revealed an optimized sequence with a GC content of 49.776 % and a CAI of 0.982. The immunological simulation results showed strong immune responses, with elevated levels of active and plasma B-cells, regulatory T-cells, HTL, and CTL in both IgM+IgG and secondary immune responses. The antigen was completely cleared by the 50th day. This study lays the foundation for creating a potent and secure vaccine candidate to combat the newly identified M. pulmonis infection in people.
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Vacunas Bacterianas , Epítopos de Linfocito B , Epítopos de Linfocito T , Aprendizaje Automático , Infecciones por Mycoplasma , Proteómica , Vacunas Bacterianas/inmunología , Infecciones por Mycoplasma/prevención & control , Infecciones por Mycoplasma/inmunología , Proteómica/métodos , Animales , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito B/inmunología , Linfocitos T Citotóxicos/inmunología , Humanos , Proteínas Bacterianas/inmunología , Ratones , Simulación del Acoplamiento Molecular , Mapeo Epitopo/métodos , Antígenos Bacterianos/inmunologíaRESUMEN
INTRODUCTION: Chickens with Necrotic Enteritis (NE), caused by Clostridium perfringens, exhibit acute and chronic symptoms that are difficult to diagnose, leading to significant economic losses. Vaccination is the best method for controlling and preventing NE. However, only two vaccines based on the CPA and NetB toxins have been commercialized, offering partial protection, highlighting the urgent need for more effective vaccines. OBJECTIVE: This review aimed to identify promising antigens for NE vaccine formulation and discuss factors affecting their effectiveness. METHODS: A systematic review using five scientific databases identified 30 eligible studies through the Rayyan tool, which were included for quality review. RESULTS: We identified 25 promising antigens, including CPA, NetB, FBA, ZMP, CnaA, FimA, and FimB, categorized by their role in disease pathogenesis. This review discusses the biochemical, physiological, and genetic traits of recombinant antigens used in vaccine prototypes, their expression systems, and immunization potential in chickens challenged with virulent C. perfringens strains. Market supply challenges, immunogenic potential, vaccine platforms, adjuvants, and factors related to vaccination schedules-such as administration routes, dosing intervals, and age at immunization-are also addressed. Additionally, the study notes that vaccine formulations tested under mild challenges may not offer adequate field-level protection due to issues replicating aggressive conditions, strain virulence loss, and varied methodologies. CONCLUSIONS: An ideal NE vaccine should incorporate multiple antigens, molecular adjuvants, and delivery systems via in ovo and oral routes. The review underscores the challenges in developing and validating NE vaccines and the urgent need for a standardized protocol to replicate aggressive challenges accurately.
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Vacunas Bacterianas , Pollos , Infecciones por Clostridium , Clostridium perfringens , Enteritis , Enfermedades de las Aves de Corral , Animales , Clostridium perfringens/inmunología , Clostridium perfringens/genética , Enteritis/prevención & control , Enteritis/veterinaria , Enteritis/microbiología , Enteritis/inmunología , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Enfermedades de las Aves de Corral/prevención & control , Enfermedades de las Aves de Corral/microbiología , Infecciones por Clostridium/prevención & control , Infecciones por Clostridium/veterinaria , Infecciones por Clostridium/inmunología , Antígenos Bacterianos/inmunología , Desarrollo de Vacunas/métodos , Vacunación/veterinaria , Vacunación/métodos , Necrosis/veterinariaRESUMEN
The emergence of multidrug-resistant Klebsiella pneumoniae poses a grave threat to global public health, necessitating urgent strategies for vaccine development. In this context, computational tools have emerged as indispensable assets, offering unprecedented insights into klebsiellal biology and facilitating the design of effective vaccines. Here, a review of the application of computational methods in the development of K. pneumoniae vaccines is presented, elucidating the transformative impact of in silico approaches. Through a systematic exploration of bioinformatics, structural biology, and immunoinformatics techniques, the complex landscape of K. pneumoniae pathogenesis and antigenicity was unravelled. Key insights into virulence factors, antigen discovery, and immune response mechanisms are discussed, highlighting the pivotal role of computational tools in accelerating vaccine development efforts. Advancements in epitope prediction, antigen selection, and vaccine design optimisation are examined, highlighting the potential of in silico approaches to update vaccine development pipelines. Furthermore, challenges and future directions in leveraging computational tools to combat K. pneumoniae are discussed, emphasizing the importance of multidisciplinary collaboration and data integration. This review provides a comprehensive overview of the current state of computational contributions to K. pneumoniae vaccine development, offering insights into innovative strategies for addressing this urgent global health challenge.
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Vacunas Bacterianas , Biología Computacional , Simulación por Computador , Infecciones por Klebsiella , Klebsiella pneumoniae , Klebsiella pneumoniae/inmunología , Vacunas Bacterianas/inmunología , Humanos , Biología Computacional/métodos , Infecciones por Klebsiella/inmunología , Infecciones por Klebsiella/prevención & control , Infecciones por Klebsiella/microbiología , Desarrollo de Vacunas , Factores de Virulencia/inmunología , AnimalesRESUMEN
There are currently no vaccines available to prevent and control of Anaplasma phagocytophilum, an intracellular bacterial pathogen transmitted by ticks that occurs in many regions of the world and causes disease in a wide range of domestic and wild hosts, including humans. Vaccines induce long-lasting immunity and could prevent or reduce transmission of this pathogen. Understanding how vaccines induce a protective response can be difficult due to the complexity of the immune system, which operates at many levels throughout the organism. New perspectives in vaccinology, based on systems biology approaches, integrate many scientific disciplines to fully understand the biological responses to vaccination, where a transcriptomic approach could reveal relevant information of the host immune system, allowing profiling for rational design of vaccine formulations, administration, and potential protection. In the present study we report the gene expression profiles by RNA-seq followed by functional analysis using whole blood samples from rabbits immunized with a recombinant chimeric protein containing peptides from the MSP4 protein of A. phagocytophilum, which showed satisfactory results in terms of potential protection. Transcriptomic analysis revealed differential expression of 720 genes, with 346 genes upregulated and 374 genes downregulated. Overrepresentation of biological and metabolic pathways correlated with immune response, protein signaling, cytoskeleton organization and protein synthesis were found. These changes in gene expression could provide a complete and unique picture of the biological response to the epitope candidate vaccine against A. phagocytophilum in the host.
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Anaplasma phagocytophilum , Vacunas Bacterianas , Animales , Conejos , Anaplasma phagocytophilum/inmunología , Vacunas Bacterianas/inmunología , Vacunación , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/genética , Ehrlichiosis/prevención & control , Ehrlichiosis/inmunología , Ehrlichiosis/veterinaria , Transcriptoma , Proteínas Bacterianas/genética , Proteínas Bacterianas/inmunología , Expresión Génica , FemeninoRESUMEN
INTRODUCTION: Producing commercial bacterins/toxoids against Clostridium spp. is laborious and hazardous. Conversely, developing prototype vaccines using purified recombinant toxoids, though safe and effective, is both laborious and costly for application in production animals. OBJECTIVE: Considering that inactivated recombinant Escherichiacoli (bacterin) is a simple, cost-effective, and to be safe solution, we evaluated, for the first time, a pentavalent formulation of recombinant bacterins containing the alpha, beta, and epsilon toxins of Clostridiumperfringens and C and D neurotoxins of Clostridiumbotulinum in sheep. METHODS: Subcutaneously, 18 Texel sheep received two doses (200 µg of each antigen) of recombinant bacterin (n = 7) or purified recombinant antigens (n = 6) on days 0 and 28, while the control group (n = 5) did not receive an immunization. Sera samples from days 0 (before the 1st dose), 28 (before the 2nd dose), and 56, 84, and 112 were used for measuring IgG (indirect ELISA) and neutralizing antibodies (mouse serum neutralization). RESULTS: Both formulations induced significant levels of IgG against all five toxins (p < 0.05) up to day 112, with peaks at days 28 and 56 post-immunization. The expected booster effect occurred only for the botulinum toxins. The neutralizing antibody titers were satisfactory against ETX (≥2 IU/ml for both formulations) and BoNT-D [5 IU/ml (bacterin) and 10 IU/ml (purified)]. CONCLUSION: While adjustments are required, the recombinant bacterin platform holds great potential for polyvalent vaccines due to its straightforward, safe, and cost-effective production, establishing it as a user-friendly technology for the veterinary immunobiological industry.
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Anticuerpos Antibacterianos , Anticuerpos Neutralizantes , Vacunas Bacterianas , Botulismo , Enterotoxemia , Animales , Botulismo/prevención & control , Botulismo/veterinaria , Botulismo/inmunología , Ovinos , Vacunas Bacterianas/inmunología , Vacunas Bacterianas/administración & dosificación , Vacunas Bacterianas/genética , Anticuerpos Antibacterianos/sangre , Enterotoxemia/prevención & control , Enterotoxemia/inmunología , Anticuerpos Neutralizantes/sangre , Anticuerpos Neutralizantes/inmunología , Enfermedades de las Ovejas/prevención & control , Enfermedades de las Ovejas/inmunología , Enfermedades de las Ovejas/microbiología , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Inmunoglobulina G/sangre , Escherichia coli/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , FemeninoRESUMEN
INTRODUCTION: Clostridioides difficile is the main cause of antibiotic-associated diarrhea in humans and is a major enteropathogen in several animal species. In newborn piglets, colonic lesions caused by C. difficile A and B toxins (TcdA and TcdB, respectively) cause diarrhea and significant production losses. OBJECTIVE: The present study aimed to develop two recombinant vaccines from immunogenic C-terminal fragments of TcdA and TcdB and evaluate the immune response in rabbits and in breeding sows. Two vaccines were produced: bivalent (rAB), consisting of recombinant fragments of TcdA and TcdB, and chimeric (rQAB), corresponding to the synthesis of the same fragments in a single protein. Groups of rabbits were inoculated with 10 or 50 µg of proteins adjuvanted with aluminum or 0.85 % sterile saline in a final volume of 1 mL/dose. Anti-TcdA and anti-TcdB IgG antibodies were detected in rabbits and sows immunized with both rAB and rQAB vaccines by ELISA. The vaccinated sows were inoculated intramuscularly with 20 µg/dose using a prime-boost approach. RESULTS: Different antibody titers (p ≤ 0.05) were observed among the vaccinated groups of sows (rAB and rQAB) and control. Additionally, newborn piglets from vaccinated sows were also positive for anti-TcdA and anti-TcdB IgGs, in contrast to control piglets (p ≤ 0.05). Immunization of sows with the rQAB vaccine conferred higher anti-TcdA and anti-TcdB responses in piglets, suggesting the superiority of this compound over rAB. CONCLUSION: The synthesized recombinant proteins were capable of inducing antibody titers against C. difficile toxins A and B in sows, and were passively transferred to piglets through colostrum.