Search Results (2,506)

Brucellosis is a globally prevalent zoonotic disease affecting both humans and animals. Its nonspecific clinical manifestations often complicate diagnosis, underscoring the need for reliable laboratory confirmation. Traditional serological assays, though widely used, suffer from limitations such as inconsistent sensitivity and false-positive results. To address these challenges, this study mapped IgM and IgG epitopes of the Brucella Omp-2a protein using sera from infected patients. Epitope identification was performed through SPOT synthesis on cellulose membranes, followed by assessment of potential cross-reactivity using peptide database analysis and ELISA validation. Three major IgM and seven IgG linear B-cell epitopes were identified, six of which demonstrated strong reactivity in peptide-ELISA. Importantly, no significant cross-reactivity with proteins from other human pathogens was detected. Two chimeric multi-epitope peptides, composed of 50 and 60 amino acids and integrating Brucella-specific IgM and IgG epitopes, exhibited excellent diagnostic performance in ELISA, achieving near 100% sensitivity and specificity. These findings support the potential of synthetic peptides as reliable and cost-effective alternatives to native antigens in serological assays. Further validation in larger, geographically diverse cohorts will be essential to confirm their diagnostic robustness and facilitate their integration into routine brucellosis diagnostics. Full article

Background: Vitamin D, through its role in antimicrobial peptide (AMP) expression, may influence innate immunity and inflammation in urinary tract infections (UTIs). This study evaluated its role in patients with vesicoureteral reflux (VUR) and its contribution to the pathophysiology of reflux nephropathy (RN). Methods: We conducted a cross-sectional observational study of 25 pediatric patients with VUR, representing a subgroup analysis of a larger cohort examined in a previous study. We determined patients’ vitamin D status, correlated it with recurrent UTIs and RS, and explored its relationship with urinary LL-37, NGAL, and IL-6 levels as markers of innate immune function. Results: Serum vitamin D levels ranged from 10.7 to 123.2 ng/mL (mean 39.5 ng/mL); 12% had deficiency and 20% had insufficient levels. Low vitamin D levels were detected in patients with more than five acute pyelonephritis (APNs), with a mean value classified as insufficient (27.3 ng/mL). Patients with RS had a lower mean vitamin D level compared to those without (30.51 ng/mL vs. 41.23 ng/mL), though the difference was not statistically significant (p = 0.39). No significant associations were found between vitamin D and urinary IL-6 or NGAL levels. A strong positive correlation was observed between vitamin D and urinary LL-37/creatinine (r = 0.78, r² = 0.61). Conclusions: Vitamin D appears to influence the frequency of UTIs and the development of RS, primarily by modulating LL-37 secretion, suggesting a possible role in the pathophysiology of RN. Full article

The Hsp20 protein family, essential in heat stress responses across all organisms, is part of the heat shock protein (Hsp) superfamily, recognized for its conserved alpha-crystallin domain (ACD). Hsp20s are the smallest proteins in the superfamily and primarily assist in protein refolding during stress and developmental processes. We present an in silico characterization of the Hsp20 gene family in Chenopodium quinoa (2n = 4x = 36) using an integrative approach. Quinoa is well known for its global contributions to food production and tolerance to various abiotic stresses. We identified 69 CqHsp20 genes that exhibit a well-conserved evolutionary pattern, characterized by a balanced copy number distributed symmetrically across 19 homeologous pairs in both subgenomes (A and B), with localized expansions driven by tandem duplications on eight chromosomes. High sequence identity in contiguous gene pairs and Ka/Ks ratios consistently below 1 (0.14–0.84) mathematically demonstrate that strict purifying selection has maintained the structural and sequence integrity of these genes since the ancestral polyploidization event. The phylogenetic analysis grouped CqHsp20 into two main clusters, splitted into four sub-clusters based on peptides’ cellular localization, consistent with a characteristic gene structure and conserved motif analysis, which may reflect the evolutionary trajectory and functional specialization of the Hsp20 family in plants. The integration of transcriptomic data from published experiments enabled us to detect a cluster of putatively ubiquitously expressed CqHsp20, as well as other groups that showed differential responses across abiotic stress conditions. The pattern shows that more genes exhibit higher transcription abundance under drought and salinity than under heat, key adaptive traits underlying quinoa’s known ecological versatility. Some of these genes, which are undetectable or have low abundance under heat stress, encode organelle-targeting peptides, a phenomenon not reported in other model plant studies. Differential expression analysis revealed a highly transcribed sub-cluster where six out of seven of nuclear CqHsp20 genes were active in aerial tissue during initial heat stress, with a specific cohort of four genes (CQ025082, CQ031384, CQ041158, and CQ055373) maintaining significant upregulation ($|{log}_2\mathrm{Fold}\mathrm{Change}|\ge 1.0$, $\mathrm{padj}<0.05$) under prolonged and simultaneous shoot/root exposure. Varying expression within CqHsp20 homologous and paralogs supports the idea that gene duplication creates genomic diversity, facilitating adaptation to variable extreme environments. However, while theoretical and in silico analysis provide valuable insight into quinoa Hsp20 response, empirical data are essential to unequivocally understand how these gene expression variations affect quinoa response to abiotic stressors. Full article

In recent years, cruor from slaughterhouse blood has garnered growing interest as a potential source of antimicrobial peptides obtained through enzymatic hydrolysis. In addition, electrodialysis with ultrafiltration membrane (EDUF) represents a strategy for valorizing peptide-rich hydrolysates, enabling the selective separation and concentration of antimicrobial peptides, according to their size and charge. Hence, this study evaluated the potential of EDUF to fractionate, for the first time, calf cruor hydrolysate and explore its use as a novel source of antimicrobial peptides. The resulting peptide fractions were characterized to investigate the selectivity of peptide migration in relation to peptide physico-chemical characteristics and membrane properties and to finally assess their antimicrobial activity. High migration rates of 12.75 ± 2.17 g/m²h and 8.94 ± 0.38 g/m²h were observed for the cationic (P⁺) and anionic (P⁻) recovery fractions, respectively. These results suggested that peptide migration from calf cruor hydrolysate to both recovery fractions during EDUF was influenced by the combined effects of molecular weight, net charge, hydrophobicity, specific amino acid residues (L, Y), and peptide–membrane interactions. Furthermore, the initial and final hydrolysates as well as P⁺ fractions exhibited antifungal activities against Paecilomyces spp. and Rhodotorula mucilaginosa with minimum inhibitory concentrations (MIC) ranging from 0.312 to 0.615 mg/mL and minimum fungicidal concentrations (MFCs) ranging from 0.312 to 1.250 mg/mL. In contrast, the P⁻ fraction did not exhibit antifungal activity, but a slight anti-Listeria activity was detected, with a MIC of 10 mg/mL. These findings highlight the potential of upcycling calf blood into functional antifungal and antibacterial agents, supporting a circular economy approach and transforming waste streams into value-added ingredients that enhance food preservation. Full article

Marine-derived collagen peptides exhibit potent intestinal barrier protection; however, their gastrointestinal fate and molecular targets remain unclear, limiting their practical applications. This study investigated the digestive stability and transepithelial transport of GPSGPQGSR, a mucoprotective peptide from Alaska pollock (Gadus chalcogrammus) skin, using simulated gastrointestinal digestion, a Caco-2 cell transport model, and an UPLC-QTOF-MS/MS. The results showed that GPSGPQGSR was a digestion-resistant peptide that reached the intestinal epithelium intact. Although brush border membrane enzymes partially hydrolysed the peptide, 42.16% of intact GPSGPQGSR remained in the luminal compartment after 2 h of incubation. No intact peptide was detected in the basolateral compartment. Molecular docking and 100 ns molecular dynamics simulations identified TLR2 (−14.936 kcal/mol) and PAR2 (−10.154 kcal/mol) as high-affinity extracellular targets of GPSGPQGSR, with stable peptide–receptor interactions and extensive hydrogen bonding networks between the peptide and each receptor (RMSD of 1.8 Å and 2.2 Å, respectively). Pharmacological blockade of TLR2 or PAR2 abolished the protective effects of GPSGPQGSR. These findings demonstrate that GPSGPQGSR acts as a digestion-resistant extracellular signalling peptide that reaches the intestinal epithelium intact and protects barrier function through apical TLR2 and PAR2, providing a mechanistic basis for the rational development of marine collagen peptides for improving intestinal health. Full article

Background/Objectives: Canine papillomavirus (CPV) is an important viral pathogen associated with papillomatosis in dogs, with canine papillomavirus type 1 (CPV1) and type 2 (CPV2) among the most prevalent and clinically relevant genotypes. The L1 capsid protein is a major immunogenic antigen of papillomaviruses; however, conserved linear B-cell epitopes shared between CPV genotypes remain poorly defined. This study aimed to identify conserved cross-reactive B-cell epitopes within CPV1 and CPV2 L1 proteins and to evaluate their preliminary immunoreactivity. Methods: Conserved linear B-cell epitopes were predicted through integrated bioinformatic and structural analyses based on sequence conservation and surface accessibility. Three candidate epitopes were selected. Recombinant CPV1 and CPV2 L1 proteins were expressed in Escherichia coli (E. coli), purified, used as recombinant L1 antigens, together with BSA-conjugated synthetic epitope peptides for mouse immunization. Antigen-specific IgG responses were assessed by ELISA, antigen-associated IFN-γ responses were evaluated by ELISpot, and cross-reactive antibody recognition was assessed by Western blot. Results: Recombinant L1 proteins induced strong antigen-specific IgG responses in mice. The selected peptides induced detectable but weaker humoral responses compared with the recombinant L1 proteins. Among the three epitopes, TPSGSLV and TVVDNTR elicited antibodies that recognized both CPV1 and CPV2 L1 proteins, while the epitope VIVPKVS showed minimal or no detectable immunoreactivity. ELISpot analysis showed only modest antigen-associated IFN-γ responses, particularly in peptide-immunized groups. Conclusions: This study identified conserved cross-reactive linear B-cell epitope candidates within CPV1 and CPV2 L1 proteins and provided preliminary immunological evidence supporting their potential relevance for CPV antigen design. However, peptide-induced responses were weaker than those induced by recombinant L1 proteins, and VLP formation, antibody neutralizing activity, and protective efficacy were not evaluated. Further studies in dogs, including optimized antigen-display platforms, neutralization assays, and protection studies, are required to determine the practical value of these epitopes for CPV vaccine development. Full article

Background: The incidence of cancer-associated thromboembolism has been extensively investigated, but mostly in heterogeneous cancer populations. Prognostic risk assessment is crucial in pulmonary embolism, but the accuracy of the commonly used tools remains uncertain in patients with cancer. Methods: We retrospectively included outpatients with consecutive lung cancer attending the Pulmonary Unit in Pisa from July 2019 to June 2021. The study population was the subgroup of patients who developed at least one episode of pulmonary embolism. For all patients, clinical data within 72 h of pulmonary embolism diagnosis, Khorana Risk Score, and overall survival time were collected. Results: A total of 512 patients with lung cancer attended the clinic; 40 patients developed pulmonary embolism (cumulative incidence of 7.81%). Eight patients (20%) died within a month, and twenty-two patients (55%) died within 6 months. Troponin, N-terminal pro-brain-type natriuretic peptide and shock index were significantly different between survivors and non-survivors (p < 0.05). Pulmonary artery diameter and the right to left ventricle index were not significantly different between survivors and non-survivors. Patients’ survival significantly decreased with the increase in Khorana Risk Score. Conclusions: Compared to previous studies, a higher incidence of pulmonary embolism in lung cancer was detected by our study. The prognosis of patients with lung cancer with pulmonary embolism seemed to be influenced more by the natural history of cancer than by the severity of pulmonary embolism. Khorana Risk Score might be considered as a prognostic tool in patients with lung cancer and may be used in the prognostic work-up for lung cancer-associated thromboembolism after a prospective validation. Full article

Background: Glucagon-like peptide-1 receptor (GLP1R) agonists, particularly semaglutide, show neuroprotective effects in genetic models of Alzheimer’s disease (AD). However, their delayed and long-term effects in sporadic AD, such as the intracerebroventricular streptozotocin (STZ) injection, remain insufficient. It is unclear how long the effects of GLP1R agonists persist after discontinuation and whether a single course can suppress progressive neurodegeneration. This study aimed to evaluate the delayed effects of semaglutide administration on morphological changes in neurons and glial cells in the hippocampus associated with cognitive impairment in an STZ-induced rat model of AD. Methods: Rats received bilateral intracerebroventricular STZ injections (3 mg/kg) followed by a 5-week course of intraperitoneal administration of semaglutide (0.1 mg/kg, every other day), and were euthanized 60 days after discontinuation of semaglutide administration. Immunomorphological methods were used to detect neuronal, astrocytic and microglial alterations. A novel object recognition test was performed to assess behavioral effects. Results: STZ-treated animals demonstrated cognitive impairments, ventriculomegaly, a significant increase in p-tau protein fluorescence intensity (p = 0.02), a decrease in CA1–CA3 field area (by 23%, p = 0.008), and reduced hippocampal neuronal density. Decreases in TOMM20 (mitochondrial marker) and synaptophysin levels were accompanied by significant glial activation in the hippocampal CA3 field. Semaglutide administration significantly reduced the enlarged ventricular lumen (by 43.5%), decreased p-tau fluorescence intensity, reduced vimentin-positive reactive astrocytes (by 68.4%), and increased synaptophysin fluorescence intensity. Furthermore, it reduced microglial activation (decreasing IBA1 cell density and elongation) and alleviated the disrupted AQP4 distribution. However, semaglutide did not completely halt the neurodegenerative process and showed no effect on the number of doublecortin-positive cells in the dentate gyrus. Conclusions: Hippocampal changes assessment revealed that course administration of semaglutide exerts prolonged effects, attenuating the severity of pathomorphological alterations and behavioral changes in a sporadic AD model after drug discontinuation. Full article

Background/Objectives: Osteoporosis (OP) is a frequent complication of rheumatoid arthritis (RA), driven by chronic inflammation and subsequent bone destruction. While deer bone is recognized for its potential bone-health benefits, the therapeutic efficacy of its fermented products on RA-induced OP remains unclear. Methods: This study investigated the protective effects of Lactobacillus reuteri-fermented deer bone water extract (LR-DBW) against OP in an adjuvant arthritis (AA) rat model. Firstly, LC-MS/MS was employed to analyze the differential peptide profiles between LR-DBW and non-fermented deer bone water extract (DBW). Secondly, experiments such as Micro-CT, histological staining, and Western Blot were conducted to detect the improvement effect of LR-DBW on OP. Results:In vivo, LR-DBW administration significantly alleviated arthritis symptoms, increased bone mineral density (BMD), and improved bone microarchitecture in AA rats. In vitro, LR-DBW inhibited RANKL-induced osteoclastogenesis and actin ring formation in RAW264.7 cells. Mechanistically, LR-DBW inhibits the phosphorylation of ERK, JNK and p38 proteins. Conclusions: These research results indicate that one of the mechanisms by which inhibiting osteoclast differentiation into LR-DBW can alleviate osteoporosis caused by rheumatoid arthritis is through down-regulating the phosphorylation expression of ERK, JNK and p38 proteins. This highlights its potential as a functional food component for treating inflammatory bone diseases. Full article

Background: The translocation of diet-derived antigens from the maternal intestine to breast milk represents a primary gateway for neonatal immune priming, yet the structural basis for why certain proteins survive this transit while others do not remains poorly understood. This review introduces the “Survivor Peptide” hypothesis, proposing that specific food allergens possess intrinsic “stability architectures” that enable them to resist maternal digestion and navigate the gut–mammary axis to reach the infant in an immunologically active form. Methods: We analyzed the current literature regarding the detection and structural characteristics of food allergens in human milk. Integrating evidence from 26 major sources, we performed an in silico structural analysis of five representative “survivor” proteins: Gal d 1 (egg white), Bos d 5 (cow’s milk), Gal d 6 (egg yolk), Tri a 19 (wheat), and tropomyosin (Der p 10-mite/shellfish). High-resolution 3D models were retrieved from the Protein Data Bank and AlphaFold2, and then visualized in UCSF ChimeraX to map stability anchors, including disulfide bonds and hydrophobic clusters, against solvent-accessible IgE-binding epitopes. Results: We identified and categorized allergens into distinct Molecular Resilience Architectures: the “Covalent Cage” (Gal d 1), defined by dense disulfide stapling, the “Glycoprotein Shield” (Gal d 6), utilizing yolk-matrix structural anchors, the “Topological Shield” (Bos d 5), characterized by a stable β-barrel, and “Coiled-Coil Rigidity” (Der p 10). These frameworks protect large, immunogenic fragments that maintain the spatial arrangement required for IgE cross-linking. Conclusions: Allergen persistence in the gut–mammary axis is dictated by a protein’s intrinsic structural architecture. Identifying these stability fingerprints provides a unified theory for allergen persistence and offers a path for refining component-resolved diagnostics and neonatal oral tolerance strategies. Full article

The Getah virus (GETV) is a mosquito-borne pathogen that infects diverse hosts, including pigs, horses, and humans, which can cause swine reproductive disorders such as abortion and stillbirth, posing a potential threat to animal and public health. Therefore, there is an urgent need for efficient and accurate serological diagnostic methods for surveillance and control of GETV. However, commercial diagnostic kits for swine GETV infection remain unavailable. In this study, we developed a novel enzyme-linked immunosorbent assay (ELISA) based on a GETV-specific epitope peptide (E2EP3) for serological detection. The N-terminally biotinylated E2EP3 peptide was synthesized, and the reaction conditions were systematically optimized, resulting in a cut-off value of 0.363. The assay exhibited no cross-reactivity with Japanese encephalitis virus (JEV), porcine circovirus type 2 (PCV2), porcine circovirus type 3 (PCV3), pseudorabies virus (PRV), or classical swine fever virus (CSFV). It demonstrated good reproducibility and high sensitivity, detecting GETV-positive serum diluted up to 1:640. The overall agreement rate reached 95%, consistent with a conventional recombinant GETV E2 protein-based ELISA. Benefiting from the biotin–streptavidin system, this assay achieved strong signal amplification and low background. Moreover, the procedure is simple, cost-effective, and stable, making it suitable for GETV large-scale serological surveillance and vaccine evaluation. Full article

Honeybee (Apis mellifera) health is governed by the integrated action of detoxification, immunity, and microbiota within complex environmental contexts. The coordinated detoxification system (DETOXome), primarily active in the midgut, fat body, and Malpighian tubules, includes cytochrome P450s, glutathione S transferases, carboxylesterases, and ABC transporters, and functions in concert with innate immune pathways such as Toll, Imd, Jak/STAT, JNK, antimicrobial peptides, and RNA interference. Cellular maintenance mechanisms, including heat shock proteins, proteostasis, and antioxidant defenses, support these systems under chemical, thermal, and pathogen-induced stress. Multi-stressor exposures encompassing pesticides, pathogens, nutritional limitations, and climate variations interact to affect physiological resilience, behavior, and colony function. This review synthesizes molecular, organ-specific, and colony-level evidence to provide a mechanistic framework connecting environmental stressors to detoxification and immune responses. Predictive markers derived from transcriptomic, proteomic, and microbiome analyses offer early detection of sublethal stress, while genomic and selective breeding strategies hold the potential to enhance honeybee resilience. By integrating stress pathways across biological scales, this review advances a unified model of honeybee health that moves beyond descriptive lists to highlight cross-system interactions driving colony survival. Full article

Immune checkpoint inhibitors (ICIs) have transformed the therapeutic landscape of oncology but are increasingly associated with cardiovascular immune-related adverse events (irAEs), including myocarditis, heart failure, arrhythmias, and vascular complications. Among these, ICI-associated myocarditis represents the most severe manifestation, often characterized by high mortality and challenging early diagnosis. Detecting subclinical myocardial injury before irreversible cardiomyocyte necrosis occurs remains a major unmet need in contemporary cardio-oncology. This narrative expert review critically examines the biological rationale, preclinical evidence, and emerging clinical data supporting the potential role of heart-type fatty acid-binding protein (H-FABP) as an adjunctive biomarker of early immune-mediated myocardial injury during ICI therapy. H-FABP is a small cytosolic lipid chaperone abundantly expressed in cardiomyocytes and rapidly released into the circulation following subtle membrane destabilization and metabolic stress, frequently preceding detectable troponin elevation in other forms of myocardial injury. Experimental studies support a mechanistic association between H-FABP release, inflammasome activation, cytokine amplification, mitochondrial dysfunction, and immune–metabolic cardiomyocyte stress. Preliminary clinical observations further suggest that H-FABP elevations may occur during ICI treatment even in the absence of overt myocarditis or concomitant increases in high-sensitivity cardiac troponins (hs-cTns). Although H-FABP cannot replace hs-cTn, which remains the cornerstone biomarker for the diagnosis of clinically significant ICI-associated myocarditis, its rapid kinetics and sensitivity to early metabolic membrane injury support its potential role as an investigational adjunctive biomarker for early surveillance and risk stratification. This approach may be particularly relevant in patients receiving high-risk combination ICI regimens or in individuals with pre-existing cardiovascular disease. However, current evidence remains limited, and large prospective multicenter studies integrating H-FABP with hs-cTns, natriuretic peptides, cardiac magnetic resonance imaging, and clinical outcomes are required before routine clinical implementation can be considered. Full article

In this study, we combined computational predictions with experimental validation as a hybrid strategy to explore whether the E protein of tick-borne encephalitis virus (TBEV) possesses autoimmune potential. Using in silico homology searches, we identified two viral epitopes (evglekl and vtgtqgt) within the TBEV E protein that share sequence identity with fragments of the human proteins DNAH7 and CSMD2. Antibodies against these epitopes were detected in the plasma of a subset of patients after natural TBEV infection. Notably, no such antibodies were found in recipients of the Tick-E-Vac vaccine, indicating that the current vaccine does not induce cross-reactive humoral responses to these epitopes. Further computational analysis predicted that these epitopes could be presented by HLA class II molecules (alleles DRB1*09:01 and DRB1*07:01), which are known to be associated with autoimmune pathologies. Molecular dynamics simulations confirmed stable binding of the peptides within the HLA grooves, with favorable binding energies. These findings suggest a possible involvement of T-helper cells in the autoreactive process. Natural TBEV infection can give rise to antibodies against epitopes homologous to human proteins, particularly in genetically predisposed hosts. While such homology alone does not predict the onset of autoimmune disease, it represents a risk factor. Full article

Toxigenic Klebsiella oxytoca strains linked to antibiotic-associated hemorrhagic colitis produce the cytotoxins tilimycin and tilivalline, which contribute to intestinal epithelial damage during infection. Tilimycin and tilivalline are synthesized by enzymes encoded within the nonribosomal peptide synthetase (NRPS) operon, yet the regulatory mechanisms controlling operon expression remain poorly understood. SdiA, an orphan LuxR-type quorum-sensing regulator, detects exogenous N-acyl homoserine lactones (AHLs) produced by neighboring bacterial species and modulates gene expression in response to interspecies communication. Although SdiA has been implicated in virulence regulation in several enteric pathogens, its role in K. oxytoca remains unclear. This study demonstrates that SdiA positively regulates npsA, the first gene in the NRPS operon, and that this regulatory effect is enhanced in the presence of exogenous AHL. Electrophoretic mobility shift assays indicate that SdiA directly binds to the upstream regulatory region of npsA, supporting a direct interaction consistent with positive transcriptional regulation. Furthermore, deletion of sdiA significantly reduces cytotoxicity toward HeLa cells under the conditions tested. Collectively, these findings identify SdiA as a quorum-sensing-responsive activator of npsA expression and support its role in modulating cytotoxicity in toxigenic K. oxytoca strains. These results provide new insight into the influence of interspecies quorum-sensing signals on virulence-associated regulatory pathways in K. oxytoca. Full article