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Aquatic Toxicology (Amsterdam,... Jul 2024As one of the main components of marine pollution, microplastics (MPs) inevitably enter the mussel aquaculture environment. At the same time, pathogenic bacteria,...
As one of the main components of marine pollution, microplastics (MPs) inevitably enter the mussel aquaculture environment. At the same time, pathogenic bacteria, especially pathogens such as Vibrio, can cause illness outbreaks, leading to large-scale death of mussels. The potential harm of MPs and pathogenic bacteria to bivalve remains unclear. This study designed two experiments (1) mussels (Mytilus galloprovincialis) were exposed to 100 particles/L or 1,000 particles/L polymethyl methacrylate (PMMA, 17.01 ± 6.74 μm) MPs and 1 × 10 CFU/mL Vibrio parahaemolyticus at the same time (14 days), and (2) mussels were exposed to 100 particles/L or 1,000 particles/L MPs for a long time (30 days) and then exposed to 1 × 10 CFU/mL V. parahaemolyticus to explore the effects of these two stresses on the mussel immune system. The results showed that after the combined exposure of V. parahaemolyticus and MPs, the lysosomal membrane stability of hemocytes decreased, lysozyme activity was inhibited, and hemocytes were induced to produce more lectins and defensins to fight pathogenic invasion. Long-term exposure to MPs caused a large amount of energy consumption in mussels, inhibited most of the functions of humoral immunity, increased the risk of mussel infection with pathogenic bacteria, and negatively affected mussel condition factor, the number of hemocytes, and the number of byssuses. Mussels may allocate more energy to deal with MPs and pathogenic bacterial infections rather than for growth. Above all, MPs exposure can affect mussel immune function or reduce its stress resistance, which in turn has an impact on mollusk farming.
Topics: Animals; Mytilus; Microplastics; Vibrio parahaemolyticus; Water Pollutants, Chemical; Hemocytes; Muramidase; Immune System
PubMed: 38768528
DOI: 10.1016/j.aquatox.2024.106959 -
The Journal of Allergy and Clinical... May 2024Celery root is known to cause severe allergic reactions in patients sensitized to mugwort pollen.
BACKGROUND
Celery root is known to cause severe allergic reactions in patients sensitized to mugwort pollen.
OBJECTIVE
We studied clinically well-characterized patients with celery allergy by IgE testing with a comprehensive panel of celery allergens to disentangle the molecular basis of what is known as the celery-mugwort syndrome.
METHODS
Patients with suspected food allergy to celery underwent a standardized interview. Main inclusion criteria were a positive food challenge with celery or an unambiguous case history of severe anaphylaxis. IgE to celery allergens (rApi g 1.01, rApi g 1.02, rApi g 2, rApi g 4, nApi g 5, rApi g 6, rApi g 7) and to mugwort allergens (rArt v 1, rArt v 3, rArt v 4) were determined. IgE levels ≥0.35 kU/L were regarded positive.
RESULTS
Seventy-nine patients with allergy to celery were included. Thirty patients had mild oral or rhinoconjunctival symptoms, and 49 had systemic reactions. Sixty-eight percent had IgE to celery extract, 80% to birch pollen, and 77% to mugwort pollen. A combination of Api g 1.01, 1.02, 4, 5, and 7 increased the diagnostic sensitivity for celery allergy to 92%. The lipid transfer proteins Api g 2 and Api g 6 were not relevant in our celery-allergic population. IgE to Api g 7, detected in 52% of patients, correlated closely (r = 0.86) to Art v 1 from mugwort pollen. Eleven of 12 patients with monosensitization to Api g 7 were IgE negative to celery extract. The odds ratio for developing a severe anaphylactic reaction rather than only mild oral symptoms was about 6 times greater (odds ratio, 5.87; 95% confidence interval, 1.08-32.0; P = .0410) for Api g 7-sensitized versus -nonsensitized subjects.
CONCLUSION
There is an urgent need for routine diagnostic tests to assess sensitization to Api g 7, not only to increase test sensitivity but also to identify patients at risk of a severe allergic reaction to celery.
PubMed: 38763171
DOI: 10.1016/j.jaci.2024.04.030 -
Nature Communications May 2024Antimicrobial peptides (AMPs), ancient scavengers of bacteria, are very poorly induced in macrophages infected by Mycobacterium tuberculosis (M. tuberculosis), but the...
Antimicrobial peptides (AMPs), ancient scavengers of bacteria, are very poorly induced in macrophages infected by Mycobacterium tuberculosis (M. tuberculosis), but the underlying mechanism remains unknown. Here, we report that L-alanine interacts with PRSS1 and unfreezes the inhibitory effect of PRSS1 on the activation of NF-κB pathway to induce the expression of AMPs, but mycobacterial alanine dehydrogenase (Ald) Rv2780 hydrolyzes L-alanine and reduces the level of L-alanine in macrophages, thereby suppressing the expression of AMPs to facilitate survival of mycobacteria. Mechanistically, PRSS1 associates with TAK1 and disruptes the formation of TAK1/TAB1 complex to inhibit TAK1-mediated activation of NF-κB pathway, but interaction of L-alanine with PRSS1, disables PRSS1-mediated impairment on TAK1/TAB1 complex formation, thereby triggering the activation of NF-κB pathway to induce expression of AMPs. Moreover, deletion of antimicrobial peptide gene β-defensin 4 (Defb4) impairs the virulence by Rv2780 during infection in mice. Both L-alanine and the Rv2780 inhibitor, GWP-042, exhibits excellent inhibitory activity against M. tuberculosis infection in vivo. Our findings identify a previously unrecognized mechanism that M. tuberculosis uses its own alanine dehydrogenase to suppress host immunity, and provide insights relevant to the development of effective immunomodulators that target M. tuberculosis.
Topics: Mycobacterium tuberculosis; Animals; Mice; NF-kappa B; Humans; Macrophages; Alanine; Antimicrobial Peptides; Tuberculosis; Alanine Dehydrogenase; MAP Kinase Kinase Kinases; Bacterial Proteins; Signal Transduction; Mice, Inbred C57BL; RAW 264.7 Cells; Female
PubMed: 38760394
DOI: 10.1038/s41467-024-48588-4 -
Microbial Pathogenesis Jul 2024Necrotic enteritis (NE) is a potentially fatal poultry disease that causes enormous economic losses in the poultry industry worldwide. The study aimed to evaluate the...
Necrotic enteritis (NE) is a potentially fatal poultry disease that causes enormous economic losses in the poultry industry worldwide. The study aimed to evaluate the effects of dietary organic yeast-derived selenium (Se) on immune protection against experimental necrotic enteritis (NE) in commercial broilers. Chickens were fed basal diets supplemented with different Se levels (0.25, 0.50, and 1.00 Se mg/kg). To induce NE, Clostridium perfringens (C. perfringens) was orally administered at 14 days of age post hatch. The results showed that birds fed 0.25 Se mg/kg exhibited significantly increased body weight gain compared with the non-supplemented/infected birds. There were no significant differences in gut lesions between the Se-supplemented groups and the non-supplemented group. The antibody levels against α-toxin and NetB toxin increased with the increase between 0.25 Se mg/kg and 0.50 Se mg/kg. In the jejunal scrapings and spleen, the Se-supplementation groups up-regulated the transcripts for pro-inflammatory cytokines IL-1β, IL-6, IL-8, iNOS, and LITAF and avian β-defensin 6, 8, and 13 (AvBD6, 8 and 13). In conclusion, supplementation with organic yeast-derived Se alleviates the negative consequences and provides beneficial protection against experimental NE.
Topics: Animals; Chickens; Enteritis; Selenium; Poultry Diseases; Dietary Supplements; Clostridium perfringens; Clostridium Infections; Animal Feed; Cytokines; Bacterial Toxins; Necrosis; beta-Defensins; Jejunum; Spleen; Yeasts; Nitric Oxide Synthase Type II; Interleukin-6; Interleukin-8; Interleukin-1beta; Antibodies, Bacterial
PubMed: 38759933
DOI: 10.1016/j.micpath.2024.106691 -
PloS One 2024Mpox (formerly known as monkeypox) virus and some related poxviruses including smallpox virus pose a significant threat to public health, and effective prevention and...
Mpox (formerly known as monkeypox) virus and some related poxviruses including smallpox virus pose a significant threat to public health, and effective prevention and treatment strategies are needed. This study utilized a reverse vaccinology approach to retrieve conserved epitopes for monkeypox virus and construct a vaccine that could provide cross-protection against related viruses with similar antigenic properties. The selected virulent proteins of monkeypox virus, MPXVgp165, and Virion core protein P4a, were subjected to epitope mapping for vaccine construction. Two vaccines were constructed using selected T cell epitopes and B cell epitopes with PADRE and human beta-defensins adjuvants conjugated in the vaccine sequence. Both constructs were found to be highly antigenic, non-allergenic, nontoxic, and soluble, suggesting their potential to generate an adequate immune response and be safe for humans. Vaccine construct 1 was selected for molecular dynamic simulation studies. The simulation studies revealed that the TLR8-vaccine complex was more stable than the TLR3-vaccine complex. The lower RMSD and RMSF values of the TLR8 bound vaccine compared to the TLR3 bound vaccine suggested better stability and consistency of hydrogen bonds. The Rg values of the vaccine chain bound to TLR8 indicated overall stability, whereas the vaccine chain bound to TLR3 showed deviations throughout the simulation. These results suggest that the constructed vaccine could be a potential preventive measure against monkeypox and related viruses however, further experimental validation is required to confirm these findings.
Topics: Humans; Monkeypox virus; Molecular Dynamics Simulation; Epitopes, T-Lymphocyte; Epitopes, B-Lymphocyte; Computer Simulation; Poxviridae; Viral Vaccines; Epitope Mapping; Mpox (monkeypox); Animals; Toll-Like Receptor 8
PubMed: 38758816
DOI: 10.1371/journal.pone.0300778 -
Frontiers in Microbiology 2024The increasing demand for orthopedic surgeries, including joint replacements, is driven by an aging population and improved diagnosis of joint conditions. Orthopedic...
The increasing demand for orthopedic surgeries, including joint replacements, is driven by an aging population and improved diagnosis of joint conditions. Orthopedic surgeries carry a risk of infection, especially in patients with comorbidities. The rise of antibiotic resistance exacerbates this issue, necessitating alternatives like bioengineered antimicrobial peptides (AMPs), offering broad-spectrum activity and multiple action mechanisms. This review aimed to assess the prevalence of antimicrobial potential and the yield after purification among recombinant AMP families. The antimicrobial potential was evaluated using the Minimum Inhibitory Concentration (MIC) values against the most common bacteria involved in clinical infections. This systematic review adhered to PRISMA guidelines, focusing on studies of recombinant AMPs. The search strategy was run on PubMed, Scopus and Embase up to 30 March 2023. The Population, Exposure and Outcome model was used to extract the data from studies and ToxRTool for the risk of bias analysis. This review included studies providing peptide production yield data and MIC values against pathogenic bacteria. Non-English texts, reviews, conference abstracts, books, studies focusing solely on chemical synthesis, those reporting incomplete data sets, using non-standard MIC assessment methods, or presenting MIC values as ranges rather than precise concentrations, were excluded. From 370 publications, 34 studies on AMPs were analyzed. These covered 46 AMPs across 18 families, with Defensins and Hepcidins being most common. Yields varied from 0.5 to 2,700 mg/L. AMPs were tested against 23 bacterial genera, with MIC values ranging from 0.125 to >1,152 μg/mL. Arenicins showed the highest antimicrobial activity, particularly against common orthopedic infection pathogens. However, AMP production yields varied and some AMPs demonstrated limited effectiveness against certain bacterial strains. This systematic review emphasizes the critical role of bioengineered AMPs to cope infections and antibiotic resistance. It meticulously evaluates recombinant AMPs, focusing on their antimicrobial efficacy and production yields. The review highlights that, despite the variability in AMP yields and effectiveness, Arenicins and Defensins are promising candidates for future research and clinical applications in treating antibiotic-resistant orthopedic infections. This study contributes significantly to the understanding of AMPs in healthcare, underscoring their potential in addressing the growing challenge of antibiotic resistance. https://osf.io/2uq4c/.
PubMed: 38756724
DOI: 10.3389/fmicb.2024.1370826 -
BMC Microbiology May 2024The world faces a major infectious disease challenge. Interest in the discovery, design, or development of antimicrobial peptides (AMPs) as an alternative approach for...
BACKGROUND
The world faces a major infectious disease challenge. Interest in the discovery, design, or development of antimicrobial peptides (AMPs) as an alternative approach for the treatment of bacterial infections has increased. Insects are a good source of AMPs which are the main effector molecules of their innate immune system. Black Soldier Fly Larvae (BSFL) are being developed for large-scale rearing for food sustainability, waste reduction and as sustainable animal and fish feed. Bioinformatic studies have suggested that BSFL have the largest number of AMPs identified in insects. However, most AMPs identified in BSF have not yet undergone antimicrobial evaluation but are promising leads to treat critical infections.
RESULTS
Jg7197.t1, Jg7902.t1 and Jg7904.t1 were expressed into the haemolymph of larvae following infection with Salmonella enterica serovar Typhimurium and were predicted to be AMPs using the computational tool ampir. The genes encoding these proteins were within 2 distinct clusters in chromosome 1 of the BSF genome. Following removal of signal peptides, predicted structures of the mature proteins were superimposed, highlighting a high degree of structural conservation. The 3 AMPs share primary sequences with proteins that contain a Kunitz-binding domain; characterised for inhibitory action against proteases, and antimicrobial activities. An in vitro antimicrobial screen indicated that heterologously expressed SUMO-Jg7197.t1 and SUMO-Jg7902.t1 did not show activity against 12 bacterial strains. While recombinant SUMO-Jg7904.t1 had antimicrobial activity against a range of Gram-negative and Gram-positive bacteria, including the serious pathogen Pseudomonas aeruginosa.
CONCLUSIONS
We have cloned and purified putative AMPs from BSFL and performed initial in vitro experiments to evaluate their antimicrobial activity. In doing so, we have identified a putative novel defensin-like AMP, Jg7904.t1, encoded in a paralogous gene cluster, with antimicrobial activity against P. aeruginosa.
Topics: Animals; Defensins; Anti-Bacterial Agents; Diptera; Larva; Microbial Sensitivity Tests; Amino Acid Sequence; Insect Proteins; Antimicrobial Peptides; Salmonella typhimurium; Gram-Negative Bacteria
PubMed: 38755524
DOI: 10.1186/s12866-024-03325-1 -
Clinical and Experimental Vaccine... Apr 2024Enterovirus 71, a pathogen that causes hand-foot and mouth disease (HFMD) is currently regarded as an increasing neurotropic virus in Asia and can cause severe...
PURPOSE
Enterovirus 71, a pathogen that causes hand-foot and mouth disease (HFMD) is currently regarded as an increasing neurotropic virus in Asia and can cause severe complications in pediatric patients with blister-like sores or rashes on the hand, feet, and mouth. Notwithstanding the significant burden of the disease, no authorized vaccine is available. Previously identified attenuated and inactivated vaccines are worthless over time owing to changes in the viral genome.
MATERIALS AND METHODS
A novel vaccine construct using B-cell derived T-cell epitopes from the virulent polyprotein found the induction of possible immune response. In order to boost the immune system, a beta-defensin 1 preproprotein adjuvant with EAAAK linker was added at the N-terminal end of the vaccine sequence.
RESULTS
The immunogenicity of the designed, refined, and verified prospective three-dimensional-structure of the multi-epitope vaccine was found to be quite high, exhibiting non-allergenic and antigenic properties. The vaccine candidates bound to toll-like receptor 3 in a molecular docking analysis, and the efficacy of the potential vaccine to generate a strong immune response was assessed through immunological simulation.
CONCLUSION
Computational analysis has shown that the proposed multi-epitope vaccine is possibly safe for use in humans and can elicit an immune response.
PubMed: 38752008
DOI: 10.7774/cevr.2024.13.2.132 -
Cell Communication and Signaling : CCS May 2024Low sperm motility is a significant contributor to male infertility. beta-defensins have been implicated in host defence and the acquisition of sperm motility; however,...
Low sperm motility is a significant contributor to male infertility. beta-defensins have been implicated in host defence and the acquisition of sperm motility; however, the regulatory mechanisms governing their gene expression patterns and functions remain poorly understood. In this study, we performed single-cell RNA and spatial transcriptome sequencing to investigate the cellular composition of testicular and epididymal tissues and examined their gene expression characteristics. In the epididymis, we found that epididymal epithelial cells display a region specificity of gene expression in different epididymal segments, including the beta-defensin family genes. In particular, Defb15, Defb18, Defb20, Defb25 and Defb48 are specific to the caput; Defb22, Defb23 and Defb26 to the corpus; Defb2 and Defb9 to the cauda of the epididymis. To confirm this, we performed mRNA fluorescence in situ hybridisation (FISH) targeting certain exon region of beta-defensin genes, and found some of their expression matched the sequencing results and displayed a close connection with epididimosome marker gene Cd63. In addition, we paid attention to the Sertoli cells and Leydig cells in the testis, along with fibroblasts and smooth muscle cells in the epididymis, by demonstrating their gene expression profile and spatial information. Our study provides a single-cell and spatial landscape for analysing the gene expression characteristics of testicular and epididymal environments and has important implications for the study of spermatogenesis and sperm maturation.
Topics: Male; Animals; beta-Defensins; Single-Cell Analysis; Mice; Transcriptome; Sperm Maturation; Epididymis; Spermatozoa; Multigene Family; Mice, Inbred C57BL; Testis
PubMed: 38745232
DOI: 10.1186/s12964-024-01637-3 -
Journal of Medical Microbiology May 2024Innovative antifungal therapies are of crucial importance to combat the potentially life-threatening infections linked to the multidrug-resistant fungal pathogen ....
Innovative antifungal therapies are of crucial importance to combat the potentially life-threatening infections linked to the multidrug-resistant fungal pathogen . Induction of regulated cell death, apoptosis, could provide an outline for future therapeutics. Human antimicrobial peptides (AMPs), well-known antifungal compounds, have shown the ability to induce apoptosis in pathogenic fungi. Although it is known that AMPs possess antifungal activity against , their ability to induce apoptosis requires further investigations. This study evaluated the effects of AMPs on the induction of apoptosis in . Human neutrophil peptide-1 (HNP-1), human β-Defensins-3 (hBD-3) and human salivary histatin 5 (His 5) were assessed against two clinical isolates. Apoptosis hallmarks were examined using FITC-Annexin V/PI double labelling assay and terminal deoxynucleotidyl transferase deoxynucleotidyl transferase nick-end labelling (TUNEL) to detect phosphatidylserine externalization and DNA fragmentation, respectively. Then, several intracellular triggers were studied using JC-10 staining, spectrophotometric assay and 2',7'-dichlorofluorescin diacetate staining to measure the mitochondrial membrane potential, cytochrome-c release and reactive oxygen species (ROS) production, respectively. FITC-Annexin V/PI staining and TUNEL analysis revealed that exposure of cells to HNP-1 and hBD-3 triggered both early and late apoptosis, while His 5 caused significant necrosis. Furthermore, HNP-1 and hBD-3 induced significant mitochondrial membrane depolarization, which resulted in substantial cytochrome c release. In contrast to His 5, which showed minimal mitochondrial depolarization and no cytochrome c release. At last, all peptides significantly increased ROS production, which is related to both types of cell death. Therefore, these peptides represent promising and effective antifungal agents for treating invasive infections caused by multidrug-resistant
Topics: Apoptosis; Humans; Antifungal Agents; Histatins; Reactive Oxygen Species; Candida auris; beta-Defensins; Membrane Potential, Mitochondrial; alpha-Defensins; Microbial Sensitivity Tests; Antimicrobial Peptides; Cytochromes c; DNA Fragmentation; Candidiasis
PubMed: 38743468
DOI: 10.1099/jmm.0.001835