RESUMEN
BACKGROUND: Helicobacter pylori (H. pylori) is a gastric Gram-negative, spiral-shaped microaerophilic pathogen. H. pylori may play a potential pathogenic role in extra-intestinal diseases such as hepatobiliary, respiratory, and dermatological disorders. The latter included chronic urticaria, psoriasis and rosacea. The first report in literature on the relationship between H. pylori and acne vulgaris (AV), found association between severe AV and H. pylori infection. There are very limited data in AV patients addressing the impact of H. pylori infection on various severities. In this context, the aim of the present work was to determine the association of H. Pylori infection among AV patients and correlate it with the disease severity. METHODS: This case-control study included 45 Patients with AV and 45 age and sex matched healthy volunteers as a control group. H. pylori antigen in stool and serum H. pylori antibody IgG using commercially available ELISA kits was tested in all included subjects. RESULTS: The percentage of participants with a positive H. pylori antigen in stool and positive H. pylori antibody in serum in the whole study population was 35/90 (38. 9%) and 41/90 (45. 6%). On comparing between the percentages of positive H. pylori antigen in stool and positive H. pylori antibody in serum between the patients with AV and healthy controls, a highly statistically significant difference was found between the two groups (P < 0.001, P = 0.006). On comparing between the percentages of positive H. pylori antigen in stool and positive H. pylori antibody in serum in the patients with different grades of acne severity and healthy controls, the rate of positive H. pylori antigen in stool and positive H. pylori Ab in serum was significantly associated with severity of acne comparing with healthy controls (p < 0. 001). CONCLUSION: The rate of H. pylori infection in patients with AV is high so it may influence the pathogenesis of this skin disease. Patients with severe AV had higher rates of H. pylori antigen in stool and H. pylori antibody in serum as compared to the patients with mild AV and healthy controls.
Asunto(s)
Acné Vulgar , Anticuerpos Antibacterianos , Infecciones por Helicobacter , Helicobacter pylori , Índice de Severidad de la Enfermedad , Humanos , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/inmunología , Acné Vulgar/microbiología , Acné Vulgar/inmunología , Masculino , Infecciones por Helicobacter/inmunología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/complicaciones , Femenino , Estudios de Casos y Controles , Adulto , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Adulto Joven , Heces/microbiología , Adolescente , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/sangre , Persona de Mediana EdadRESUMEN
Pathogen-host competition for manganese and intricate immunostimulatory pathways severely attenuates the efficacy of antibacterial immunotherapy against biofilm infections associated with orthopaedic implants. Herein, we introduce a spatiotemporal sono-metalloimmunotherapy (SMIT) strategy aimed at efficient biofilm ablation by custom design of ingenious biomimetic metal-organic framework (PCN-224)-coated MnO2-hydrangea nanoparticles (MnPM) as a metalloantibiotic. Upon reaching the acidic H2O2-enriched biofilm microenvironment, MnPM can convert abundant H2O2 into oxygen, which is conducive to significantly enhancing the efficacy of ultrasound (US)-triggered sonodynamic therapy (SDT), thereby exposing bacteria-associated antigens (BAAs). Moreover, MnPM disrupts bacterial homeostasis, further killing more bacteria. Then, the Mn ions released from the degraded MnO2 can recharge immune cells to enhance the cGAS-STING signaling pathway sensing of BAAs, further boosting the immune response and suppressing biofilm growth via biofilm-specific T cell responses. Following US withdrawal, the sustained oxygenation promotes the survival and migration of fibroblasts, stimulates the expression of angiogenic growth factors and angiogenesis, and neutralizes excessive inflammation. Our findings highlight that MnPM may act as an immune costimulatory metalloantibiotic to regulate the cGAS-STING signaling pathway, presenting a promising alternative to antibiotics for orthopaedic biofilm infection treatment and pro-tissue repair.
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Biopelículas , Compuestos de Manganeso , Óxidos , Oxígeno , Biopelículas/efectos de los fármacos , Animales , Ratones , Compuestos de Manganeso/química , Compuestos de Manganeso/farmacología , Oxígeno/metabolismo , Óxidos/farmacología , Óxidos/química , Antibacterianos/farmacología , Peróxido de Hidrógeno/metabolismo , Inmunoterapia/métodos , Humanos , Terapia por Ultrasonido/métodos , Nanopartículas/química , Transducción de Señal/efectos de los fármacos , Antígenos Bacterianos/inmunología , Staphylococcus aureus/efectos de los fármacos , FemeninoRESUMEN
The diagnosis of mycobacterial infections, including both the Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), poses a significant global medical challenge. This study proposes a novel approach using immunochromatographic (IC) strip tests for the simultaneous detection of MTBC and NTM. Traditional methods for identifying mycobacteria, such as culture techniques, are hindered by delays in distinguishing between MTBC and NTM, which can affect patient care and disease control. Molecular methods, while sensitive, are resource-intensive and unable to differentiate between live and dead bacteria. In this research, we developed unique monoclonal antibodies (mAbs) against Ag85B, a mycobacterial secretory protein, and successfully implemented IC strip tests named 8B and 9B. These strips demonstrated high concordance rates with conventional methods for detecting MTBC, with positivity rates of 93.9% and 85.9%, respectively. For NTM detection, the IC strip tests achieved a 63.2% detection rate compared to culture methods, considering variations in growth rates among different NTM species. Furthermore, this study highlights a significant finding regarding the potential of MPT64 and Ag85B proteins as markers for MTBC detection. In conclusion, our breakthrough method enables rapid and accurate detection of both MTBC and NTM bacteria within the BACTEC MGIT system. This approach represents a valuable tool in clinical settings for distinguishing between MTBC and NTM infections, thereby enhancing the management and control of mycobacterial diseases. KEY POINTS: ⢠Panel of mAbs for differentiating MTB versus NTM ⢠IC strips for diagnosing MTBC and NTM after the BACTEC MGIT ⢠Combined detection of MTP64 and Ag85B enhances diagnostic accuracy.
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Anticuerpos Monoclonales , Antígenos Bacterianos , Proteínas Bacterianas , Mycobacterium tuberculosis , Micobacterias no Tuberculosas , Tuberculosis , Mycobacterium tuberculosis/crecimiento & desarrollo , Mycobacterium tuberculosis/aislamiento & purificación , Mycobacterium tuberculosis/genética , Anticuerpos Monoclonales/inmunología , Humanos , Micobacterias no Tuberculosas/aislamiento & purificación , Micobacterias no Tuberculosas/clasificación , Micobacterias no Tuberculosas/crecimiento & desarrollo , Antígenos Bacterianos/análisis , Antígenos Bacterianos/inmunología , Tuberculosis/diagnóstico , Tuberculosis/microbiología , Proteínas Bacterianas/genética , Cromatografía de Afinidad/métodos , Sensibilidad y Especificidad , Infecciones por Mycobacterium no Tuberculosas/diagnóstico , Infecciones por Mycobacterium no Tuberculosas/microbiología , Aciltransferasas , Anticuerpos Antibacterianos/inmunologíaRESUMEN
Introduction: Tularemia, caused by the bacterium Francisella tularensis, poses health risks to humans and can spread through a variety of routes. It has also been classified as a Tier 1 Select agent by the CDC, highlighting its potential as a bioterrorism agent. Moreover, it is difficult to diagnose in a timely fashion, owing to the non-specific nature of tularemia infections. Rapid, sensitive, and accurate detection methods are required to reduce mortality rates. We aimed to develop antibodies directed against the outer membrane protein A of F. tularensis (FopA) for rapid and accurate diagnosis of tularemia. Methods: We used a baculovirus insect cell expression vector system to produce the FopA antigen and generate anti-FopA antibodies through immunization of BALB/c mice. We then employed hybridoma and phage display technologies to screen for antibodies that could recognize unique epitopes on FopA. Result: Two monoclonal antibodies, 6B12 and 3C1, identified through phage display screening specifically bound to recombinant FopA in a dose-dependent manner. The binding affinity of the anti-FopA 6B12 and 3C1 antibodies was observed to have an equilibrium dissociation constant of 1.76 × 10-10 M and 1.32 × 10-9 M, respectively. These antibodies were used to develop a sandwich ELISA system for the diagnosis of tularemia. This assay was found to be highly specific and sensitive, with detection limits ranging from 0.062 ng/mL in PBS to 0.064 ng/mL in skim milk matrices. Discussion: Our findings demonstrate the feasibility of a novel diagnostic approach for detecting F. tularensis based on targeting FopA, as opposed to existing tests that target the bacterial lipopolysaccharide.
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Anticuerpos Antibacterianos , Anticuerpos Monoclonales , Proteínas de la Membrana Bacteriana Externa , Francisella tularensis , Ratones Endogámicos BALB C , Proteínas Recombinantes , Tularemia , Tularemia/diagnóstico , Animales , Francisella tularensis/inmunología , Francisella tularensis/genética , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Anticuerpos Monoclonales/inmunología , Ratones , Inmunoensayo/métodos , Sensibilidad y Especificidad , Femenino , Técnicas de Visualización de Superficie Celular , Epítopos/inmunología , Ensayo de Inmunoadsorción Enzimática/métodos , Humanos , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/genética , Hibridomas , Baculoviridae/genéticaRESUMEN
The bacterium Clostridium botulinum, well-known for producing botulinum neurotoxins, which cause the severe paralytic illness known as botulism, produces C2 toxin, a binary AB-toxin with ADP-ribosyltranferase activity. C2 toxin possesses two separate protein components, an enzymatically active A-component C2I and the binding and translocation B-component C2II. After proteolytic activation of C2II to C2IIa, the heptameric structure binds C2I and is taken up via receptor-mediated endocytosis into the target cells. Due to acidification of endosomes, the C2IIa/C2I complex undergoes conformational changes and consequently C2IIa forms a pore into the endosomal membrane and C2I can translocate into the cytoplasm, where it ADP-ribosylates G-actin, a key component of the cytoskeleton. This modification disrupts the actin cytoskeleton, resulting in the collapse of cytoskeleton and ultimately cell death. Here, we show that the serine-protease inhibitor α1-antitrypsin (α1AT) which we identified previously from a hemofiltrate library screen for PT from Bordetella pertussis is a multitoxin inhibitor. α1AT inhibits intoxication of cells with C2 toxin via inhibition of binding to cells and inhibition of enzyme activity of C2I. Moreover, diphtheria toxin and an anthrax fusion toxin are inhibited by α1AT. Since α1AT is commercially available as a drug for treatment of the α1AT deficiency, it could be repurposed for treatment of toxin-mediated diseases.
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Toxinas Bacterianas , Toxinas Botulínicas , alfa 1-Antitripsina , Toxinas Botulínicas/metabolismo , Toxinas Botulínicas/antagonistas & inhibidores , Toxinas Botulínicas/química , Humanos , alfa 1-Antitripsina/metabolismo , alfa 1-Antitripsina/química , Toxinas Bacterianas/metabolismo , Toxina Diftérica/metabolismo , Corynebacterium diphtheriae/metabolismo , Corynebacterium diphtheriae/efectos de los fármacos , Antígenos Bacterianos/metabolismo , Animales , Clostridium botulinum/metabolismo , Bacillus anthracis/metabolismo , Bacillus anthracis/efectos de los fármacosRESUMEN
Brucellosis is a zoonotic disease caused by Brucella, which is difficult to eliminate by conventional drugs. Therefore, a novel multi-epitope vaccine (MEV) was designed to prevent human Brucella infection. Based on the method of "reverse vaccinology", cytotoxic T lymphocyte epitopes (CTLEs), helper T lymphocyte epitopes (HTLEs), linear B-cell epitopes (LBEs) and conformational B-cell epitopes (CBEs) of four Brucella proteins (VirB9, VirB10, Omp 19 and Omp 25) were obtained. In order to keep the correct protein folding, the multiple epitopes was constructed by connecting epitopes through linkers. In view of the significant connection between human leukocyte antigen CTLA-4 and B7 molecules found on antigen presenting cells (APCs), a new vaccine (V_C4MEV) for preventing brucellosis was created by combining CTLA-4 immunoglobulin variable region (IgV_CTLA-4) with MEV protein. Immunoinformatics analysis showed that V_C4MEV has a good secondary and tertiary structure. Additionally, molecular docking and molecular dynamics simulation (MD) revealed a robust binding affinity between IgV_ CTLA-4 and the B7 molecule. Notably, the vaccine V_C4MEV was demonstrated favorable immunogenicity and antigenicity in both in vitro and in vivo experiments. V_C4MEV had the potential to activate defensive cells and immune responses, offering a hopeful approach for developing vaccines against Brucella in the upcoming years.
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Vacuna contra la Brucelosis , Brucella , Brucelosis , Antígeno CTLA-4 , Biología Computacional , Epítopos de Linfocito B , Epítopos de Linfocito T , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Brucelosis/prevención & control , Brucelosis/inmunología , Epítopos de Linfocito B/inmunología , Antígeno CTLA-4/inmunología , Epítopos de Linfocito T/inmunología , Vacuna contra la Brucelosis/inmunología , Animales , Humanos , Brucella/inmunología , Brucella/genética , Ratones , Proteínas Bacterianas/inmunología , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/genética , Inmunoinformática , LipoproteínasRESUMEN
Tuberculosis (TB) is one of the leading causes of death from infectious diseases, killing approximately 1.3 million people worldwide in 2022 alone. The current vaccine for TB contains a live attenuated bacterium, Mycobacterium bovis BCG (Bacille Calmette-Guérin). The BCG vaccine is highly effective in preventing severe forms of childhood TB but does not protect against latent infection or disease in older age groups. A new or improved BCG vaccine for prevention of pulmonary TB is urgently needed. In this study, we infected murine bone marrow derived dendritic cells from C57BL/6 mice with M. bovis BCG followed by elution and identification of BCG-derived MHC class I and class II-bound peptides using tandem mass spectrometry. We identified 1436 MHC-bound peptides of which 94 were derived from BCG. Fifty-five peptides were derived from MHC class I molecules and 39 from class II molecules. We tested the 94 peptides for their immunogenicity using IFN- γ ELISPOT assay with splenocytes purified from BCG immunized mice and 10 showed positive responses. Seven peptides were derived from MHC II and three from MHC class I. In particular, MHC class II binding peptides derived from the mycobacterial surface lipoprotein Mpt83 were highly antigenic. Further evaluations of these immunogenic BCG peptides may identify proteins useful as new TB vaccine candidates.
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Antígenos Bacterianos , Vacuna BCG , Proteínas Bacterianas , Células Dendríticas , Ratones Endogámicos C57BL , Mycobacterium bovis , Animales , Antígenos Bacterianos/inmunología , Mycobacterium bovis/inmunología , Ratones , Vacuna BCG/inmunología , Proteínas Bacterianas/inmunología , Células Dendríticas/inmunología , Desarrollo de Vacunas , Femenino , Proteómica/métodos , Linfocitos T/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Lipoproteínas/inmunología , Tuberculosis/prevención & control , Tuberculosis/inmunología , Péptidos/inmunología , Proteínas de la MembranaRESUMEN
Background: To effectively control tuberculosis (TB), it is crucial to distinguish between active TB disease and latent TB infection (LTBI) to provide appropriate treatment. However, no such tests are currently available. Immune responses associated with active TB and LTBI are dynamic and exhibit distinct patterns. Comparing these differences is crucial for developing new diagnostic methods and understanding the etiology of TB. This study aimed to investigate the relationship between pro- and anti-inflammatory CD4+ cytokine production following stimulation with two types of latency-associated Mycobacterium tuberculosis (M.tb) antigens to allow differentiation between active TB and LTBI. Methods: Cryopreserved PBMCs from patients with active TB disease or LTBI were stimulated overnight with replication-related antigen [ESAT-6/CFP-10 (E/C)] or two latency-associated antigens [heparin-binding hemagglutinin (HBHA) and alpha-crystallin-like protein (Acr)]. Responses were analyzed using multiparameter flow cytometry: active TB disease (n=15), LTBI (n=15) and ELISA: active TB disease (n=26) or LTBI (n=27). Results: CD4+ central memory T cells (Tcm) specific to E/C and CD4+ effector memory T cells specific to Acr and HBHA were higher in LTBI than in TB patients. IFN-γ+Tcm and IL-17+ Tem cells was higher in the LTBI group (p= 0.012 and p=0.029 respectively), but IL-10+ Tcm was higher in the active TB group (p= 0.029) following HBHA stimulation. Additionally, following stimulation with HBHA, IL-10 production from CD4+ T cells was significantly elevated in patients with active TB compared to those with LTBI (p= 0.0038), while CD4+ T cell production of IL-17 and IFN-γ was significantly elevated in LTBI compared to active TB (p= 0.0076, p< 0.0001, respectively). HBHA also induced more CCR6+IL-17+CD4Tcells and IL-17+FoxP3+CD25+CD4Tcells in LTBI than in TB patients (P=0.026 and P=0.04, respectively). HBHA also induced higher levels of IFN-γ+IL-10+CD4+ T cells in patients with active TB (Pp=0.03) and higher levels of IFN-γ+IL-17+ CD4+ T cells in those with LTBI (p=0.04). HBHA-specific cytokine production measured using ELISA showed higher levels of IFN-γ in participants with LTBI (P=0.004) and higher levels of IL-10 in those with active TB (P=0.04). Conclusion: Stimulation with HBHA and measurement of CD4+ T cell production of IFN-γ, IL-10, and IL-17 could potentially differentiate active TB from LTBI. The characteristics of cytokine-expressing cells induced by HBHA also differed between participants with active TB and LTBI.
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Antígenos Bacterianos , Linfocitos T CD4-Positivos , Interferón gamma , Interleucina-10 , Interleucina-17 , Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis , Humanos , Masculino , Femenino , Linfocitos T CD4-Positivos/inmunología , Adulto , Interleucina-17/inmunología , Interleucina-17/metabolismo , Mycobacterium tuberculosis/inmunología , Interleucina-10/inmunología , Interferón gamma/metabolismo , Interferón gamma/inmunología , Persona de Mediana Edad , Tuberculosis Latente/inmunología , Tuberculosis/inmunología , Antígenos Bacterianos/inmunología , Anciano , Adulto Joven , LectinasRESUMEN
BACKGROUND: Helicobacter pylori (H. pylori) virulence factors, particularly the cagA and vacA genotypes, play important roles in the pathogenic process of gastrointestinal disease. METHODS: The cagA and vacA genotypes of 87 H. pylori strains were determined by PCR and sequencing. The EPIYA and CM motif patterns were analyzed and related to clinical outcomes. We examined the associations between the virulence genes of H. pylori and gastrointestinal diseases in Shandong, and the results were analyzed via the chi-square test and logistic regression model. RESULTS: Overall, 76 (87.36%) of the strains carried the East Asian-type CagA, with the ABD types being the most prevalent (90.79%). However, no significant differences were observed among the different clinical outcomes. The analysis of CagA sequence types revealed 8 distinct types, encompassing 250 EPIYA motifs, including 4 types of EPIYA or EPIYA-like sequences. Additionally, 28 CM motifs were identified, with the most prevalent patterns being E (66.67%), D (16.09%), and W-W (5.75%). Notably, a significant association was discovered between strains with GC and the CM motif pattern D (P < 0.01). With respect to the vacA genotypes, the strains were identified as s1, s2, m1, m2, i1, i2, d1, d2, c1, and c2 in 87 (100%), 0 (0), 26 (29.89%), 61 (70.11%), 73 (83.91%), 14 (16.09%), 76 (87.36%), 11 (12.64%), 18 (20.69%), and 69 (79.31%), respectively. Specifically, the vacA m1 and c1 genotypes presented a significantly greater prevalence in strains from GC compared to CG (P < 0.05). Following adjustment for age and sex, the vacA c1 genotype demonstrated a notable association with GC (OR = 5.174; 95% CI, 1.402-20.810; P = 0.012). This association was both independent of and more pronounced than the correlations between vacA m1 and GC. CONCLUSIONS: CagA proteins possessing CM motif pattern D were more frequently observed in patients with GC (P < 0.01), implying a potentially higher virulence of CM motif pattern D than the other CM motif patterns. Moreover, a strong positive association was identified between the vacA c1 genotype and GC, indicating that the vacA c1 genotype is a robust risk indicator for GC among male patients aged ≥55 years in Shandong.
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Antígenos Bacterianos , Proteínas Bacterianas , Infecciones por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Helicobacter pylori/genética , Helicobacter pylori/patogenicidad , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/genética , Humanos , Proteínas Bacterianas/genética , Masculino , Persona de Mediana Edad , Femenino , Infecciones por Helicobacter/microbiología , Antígenos Bacterianos/genética , Polimorfismo Genético , Adulto , China/epidemiología , Genotipo , Anciano , Virulencia/genética , Factores de Virulencia/genéticaRESUMEN
RATIONALE: Streptococcus pneumoniae is a common cause of community-acquired pneumonia. Currently, it is believed that many cases of pulmonary infection with negative results on pathogenic testing are caused by S. pneumoniae. There have been no reports of the detection of S. pneumoniae antigen in lung lavage fluid. PATIENT CONCERNS: An elderly male patient with suboptimal fasting blood glucose control and a history of liver abscess. DIAGNOSIS: Chest computed tomography (CT) revealed inflammatory lesions in both lungs with consolidation in the middle lobe of the right lung. INTERVENTIONS: After admission, we collected alveolar lavage fluid in a timely manner and performed pneumococcal antigen detection and etiological testing. OUTCOMES: Prompt testing for pneumococcal antigen in bronchoalveolar lavage fluid yielded a positive clinical outcome. Subsequent analysis via bacterial culture of sputum and next-generation sequencing (mNGS) of BALF definitively identified S. pneumoniae as the etiological agent. Following the analysis of drug sensitivity test results from the identified pathogens, adjustments were made to the antibiotic regimen, and appropriate pus puncture drainage was performed. Subsequently, the patient's condition improved, leading to discharge. CONCLUSION: The identification of S. pneumoniae antigen in bronchoalveolar lavage fluid may facilitate earlier and more precise diagnosis of pneumonia attributed to S. pneumoniae.
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Antígenos Bacterianos , Líquido del Lavado Bronquioalveolar , Neumonía Neumocócica , Streptococcus pneumoniae , Humanos , Masculino , Streptococcus pneumoniae/aislamiento & purificación , Streptococcus pneumoniae/inmunología , Líquido del Lavado Bronquioalveolar/microbiología , Neumonía Neumocócica/diagnóstico , Neumonía Neumocócica/microbiología , Antígenos Bacterianos/análisis , Antígenos Bacterianos/inmunología , Anciano , Neumonía Necrotizante/diagnóstico , Neumonía Necrotizante/microbiología , Antibacterianos/uso terapéutico , Tomografía Computarizada por Rayos XRESUMEN
Bacille-Calmette-Guérin (BCG) is the only approved vaccine against Mycobacterium tuberculosis (MTB), offering protection not only against tuberculosis (TB) but also non-related infections. 'Trained immunity' of innate immune cells is considered one of the mechanisms of this broad protection derived through BCG. Here, we investigated the effect of BCG on Natural Killer (NK) cells, a key innate immune cell type, and their subsequent responses to mycobacterial and HIV antigens. We found that BCG-induced KLRG1+ NK cells exhibit significantly higher production of IFNγ, compared to KLRG1- cells, indicating their memory-like responses upon exposure to these antigens (p < 0.05). These findings may be important in regions of high burden of HIV and TB where BCG is routinely administered.
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Vacuna BCG , Infecciones por VIH , Memoria Inmunológica , Interferón gamma , Células Asesinas Naturales , Lectinas Tipo C , Mycobacterium tuberculosis , Receptores Inmunológicos , Tuberculosis , Células Asesinas Naturales/inmunología , Receptores Inmunológicos/inmunología , Memoria Inmunológica/inmunología , Lectinas Tipo C/inmunología , Lectinas Tipo C/metabolismo , Humanos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Vacuna BCG/inmunología , Mycobacterium tuberculosis/inmunología , Tuberculosis/inmunología , Infecciones por VIH/inmunología , Antígenos Bacterianos/inmunología , Antígenos Virales/inmunología , Inmunización/métodosRESUMEN
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
This Medical News article discusses recent findings that help explain Staphylococcus aureus vaccine failures.
Asunto(s)
Memoria Inmunológica , Infecciones Estafilocócicas , Vacunas Estafilocócicas , Staphylococcus aureus , Animales , Humanos , Ratones , Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/efectos adversos , Antígenos Bacterianos/inmunología , Portador Sano/inmunología , Portador Sano/microbiología , Ensayos Clínicos Fase III como Asunto , Modelos Animales de Enfermedad , Interacciones Huésped-Patógeno/inmunología , Especificidad de la Especie , Infecciones Estafilocócicas/inmunología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/mortalidad , Infecciones Estafilocócicas/prevención & control , Vacunas Estafilocócicas/administración & dosificación , Vacunas Estafilocócicas/efectos adversos , Vacunas Estafilocócicas/inmunología , Staphylococcus aureus/inmunología , Staphylococcus aureus/patogenicidad , Desarrollo de VacunasRESUMEN
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/.
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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
BACKGROUND: Group A Streptococcus (Strep A) causes both uncomplicated and severe invasive infections, as well as the post-infection complications acute rheumatic fever and rheumatic heart disease. Despite the high global burden of disease resulting from Strep A infections, there is not a licensed vaccine. A 30-valent M protein-based vaccine has previously been shown to be immunogenic in animal models and in a Phase I clinical trial (NCT02564237). Here, we assessed the immunogenicity of a 30-valent messenger (m)RNA vaccine designed to express the same M peptide targets as the 30-valent protein vaccine and compared it with the protein vaccine. METHODS: Female New Zealand white rabbits were immunized with one of four vaccine formulations (3 doses of each formulation at days 1, 28, and 56): soluble mRNA (100 µg/animal), C-terminal transmembrane mRNA (100 µg/animal), protein vaccine (400 µg/animal), or a non-translatable RNA control (100 µg/animal). Serum was collected one day prior to the first dose and on days 42 and 70. Rabbit serum samples were assayed for antibody levels against synthetic M peptides by ELISA. HL-60 opsonophagocytic killing (OPK) assays were performed to assess functional antibody levels. RESULTS: Serum IgG levels were similar for the mRNA and protein vaccines. The CtTM version of the mRNA vaccine elicited slightly higher antibody levels than the mRNA designed to express soluble proteins. OPK activity was similar for the mRNA and protein vaccines, regardless of M type. CONCLUSIONS: The total antibody responses and functional antibody levels elicited by the 30-valent mRNA Strep A vaccines were similar to those observed following immunization with the analogous protein vaccine. The mRNA vaccine platform provides potential advantages to protein-based vaccines including inherent adjuvant activity, increased production efficiency, lower cost, and the potential to rapidly change epitopes/peptides, all of which are important considerations related to multivalent Strep A vaccine development.
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Anticuerpos Antibacterianos , Antígenos Bacterianos , Infecciones Estreptocócicas , Vacunas Estreptocócicas , Streptococcus pyogenes , Animales , Conejos , Femenino , Vacunas Estreptocócicas/inmunología , Vacunas Estreptocócicas/administración & dosificación , Vacunas Estreptocócicas/genética , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Infecciones Estreptocócicas/prevención & control , Infecciones Estreptocócicas/inmunología , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/genética , Streptococcus pyogenes/inmunología , Streptococcus pyogenes/genética , Inmunogenicidad Vacunal , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Portadoras/inmunología , Proteínas Portadoras/genética , Vacunas Sintéticas/inmunología , Vacunas Sintéticas/administración & dosificación , ARN Mensajero/genética , ARN Mensajero/inmunologíaRESUMEN
Helicobacter pylori infection predisposes carriers to a high risk of developing gastric cancer. The cell-of-origin of antral gastric cancer is the Lgr5+ stem cell. Here, we show that infection of antrum-derived gastric organoid cells with H. pylori increases the expression of the stem cell marker Lgr5 as determined by immunofluorescence microscopy, qRT-PCR, and Western blotting, both when cells are grown and infected as monolayers and when cells are exposed to H. pylori in 3D structures. H. pylori exposure increases stemness properties as determined by spheroid formation assay. Lgr5 expression and the acquisition of stemness depend on a functional type IV secretion system (T4SS) and at least partly on the T4SS effector CagA. The pharmacological inhibition or genetic ablation of NF-κB reverses the increase in Lgr5 and spheroid formation. Constitutively active Wnt/ß-catenin signaling because of Apc inactivation exacerbates H. pylori-induced Lgr5 expression and stemness, both of which persist even after eradication of the infection. The combined data indicate that H. pylori has stemness-inducing properties that depend on its ability to activate NF-κB signaling.
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Infecciones por Helicobacter , Helicobacter pylori , FN-kappa B , Receptores Acoplados a Proteínas G , Neoplasias Gástricas , Vía de Señalización Wnt , Animales , Ratones , Antígenos Bacterianos/metabolismo , Antígenos Bacterianos/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiología , Infecciones por Helicobacter/metabolismo , Infecciones por Helicobacter/microbiología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/microbiología , FN-kappa B/metabolismo , Organoides/metabolismo , Organoides/microbiología , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Células Madre/metabolismo , Estómago/microbiología , Estómago/patología , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Sistemas de Secreción Tipo IV/metabolismo , Sistemas de Secreción Tipo IV/genética , Vía de Señalización Wnt/genéticaRESUMEN
Helicobacter pylori (H. pylori) is a common pathogen with a high prevalence of infection in human populations. The diagnosis of H. pylori infection is critical for its treatment, eradication, and prognosis. Biosensors have been demonstrated to be powerful for the rapid onsite detection of pathogens, particularly for point-of-care test (POCT) scenarios. In this work, we propose a novel optical biosensor, based on nanomaterial porous silicon (PSi) and photonic surface state Tamm Plasmon Polariton (TPP), for the detection of cytotoxin-associated antigen A (CagA) of H. pylori bacterium. We fabricated the PSi TPP biosensor, analyzed its optical characteristics, and demonstrated through experiments, with the sensing of the CagA antigen, that the TPP biosensor has a sensitivity of 100 pm/(ng/mL), a limit of detection of 0.05 ng/mL, and specificity in terms of positive-to-negative ratio that is greater than six. From these performance factors, it can be concluded that the TPP biosensor can serve as an effective tool for the diagnosis of H. pylori infection, either in analytical labs or in POCT applications.
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Antígenos Bacterianos , Proteínas Bacterianas , Técnicas Biosensibles , Helicobacter pylori , Silicio , Técnicas Biosensibles/métodos , Silicio/química , Helicobacter pylori/inmunología , Helicobacter pylori/aislamiento & purificación , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/análisis , Proteínas Bacterianas/inmunología , Porosidad , Humanos , Infecciones por Helicobacter/diagnóstico , Infecciones por Helicobacter/microbiologíaRESUMEN
Introduction. Cytotoxin-associated gene A (CagA) from Helicobacter pylori is highly related to chronic gastritis. Tyrosine phosphorylation of Glu-Pro-Ile-Tyr-Ala (EPIYA) motifs from CagA determines the pathogenicity of H. pylori.Gap statement. The precise amino acid variations surrounding the EPIYA motifs and their correlation with clinical outcomes have been poorly explored.Aim. The purpose of this study was to examine the CagA 3' region polymorphism of H. pylori and its association with chronic gastritis in the Chinese population.Method. A total of 86 cagA-positive H. pylori strains were isolated from patients with chronic gastritis in two different hospitals in Beijing, PR China. Genomic DNA was extracted commercial kits, and the cagA 3' variable region of H. pylori was amplified by polymerase chain reaction (PCR). The PCR products were sequenced and analysed using the CLC Sequence Viewer, BioEdit, and WebLogo 3.Results. Two hundred and fifty-nine EPIYA motifs were identified from cagA-positive H. pylori strains. Notably, EPIYA-B exhibited a higher frequency of variation in comparison to EPIYA-A, EPIYA-C, and EPIYA-D. The prevalent sequences for East-Asian-type CagA were QVNK and TIDF, while KVNK and TIDD were most commonly observed for Western-type CagA. The CRPIA motifs of East-Asian-type CagA and Western-type CagA varied at positions 4, 6, 7, 8, and 10. CagA-ABD (73.2%) was the most prevalent type, followed by CagA-ABC (18.6%) and CagA-AB (3.4%). The ratio of CagA-ABD was observed to be higher in cases of chronic non-atrophic gastritis with erosive (NAGE) or chronic atrophic gastritis (AG) compared to chronic non-atrophic gastritis (NAG), and the difference was found to be statistically significant (χ2=59.000/64.000, P<0.001).Conclusions. The EPIYA segments of Western-type CagA and East-Asian-type CagA differ significantly and the presence of CagA-ABD may be associated with severe chronic gastritis from this study.
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Antígenos Bacterianos , Proteínas Bacterianas , Gastritis , Infecciones por Helicobacter , Helicobacter pylori , Polimorfismo Genético , Humanos , Antígenos Bacterianos/genética , Helicobacter pylori/genética , Helicobacter pylori/aislamiento & purificación , Helicobacter pylori/patogenicidad , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Gastritis/microbiología , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/epidemiología , Masculino , Femenino , China/epidemiología , Enfermedad Crónica , Persona de Mediana Edad , Adulto , Anciano , Pueblo Asiatico/genética , Secuencias de Aminoácidos , Pueblos del Este de AsiaRESUMEN
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.
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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
Development of a vaccine against gonorrhoea is a global priority, driven by the rise in antibiotic resistance. Although Neisseria gonorrhoeae (Ng) infection does not induce substantial protective immunity, highly exposed individuals may develop immunity against re-infection with the same strain. Retrospective epidemiological studies have shown that vaccines containing Neisseria meningitidis (Nm) outer membrane vesicles (OMVs) provide a degree of cross-protection against Ng infection. We conducted a clinical trial (NCT04297436) of 4CMenB (Bexsero, GSK), a licensed Nm vaccine containing OMVs and recombinant antigens, comprising a single arm, open label study of two doses with 50 adults in coastal Kenya who have high exposure to Ng. Data from a Ng antigen microarray established that serum IgG and IgA reactivities against the gonococcal homologs of the recombinant antigens in the vaccine peaked at 10 but had declined by 24 weeks. For most reactive OMV-derived antigens, the reverse was the case. A cohort of similar individuals with laboratory-confirmed gonococcal infection were compared before, during, and after infection: their reactivities were weaker and differed from the vaccinated cohort. We conclude that the cross-protection of the 4CMenB vaccine against gonorrhoea could be explained by cross-reaction against a diverse selection of antigens derived from the OMV component.