Search Results (1,192)

The intestinal immune system is essential for insects to defend against pathogenic infections, while the dual oxidase-reactive oxygen species (DUOX-ROS) pathway is a key component. However, the role of the DUOX-ROS pathway in Bombyx mori against Nosema bombycis, a significant pathogen of this species, remains poorly characterized. In this study, four core components of the DUOX-ROS pathway in B. mori (BmGαq, BmPLCβ1, BmPLCβ4, and BmDUOX) were identified using bioinformatics. Pathogen induction experiments showed significant upregulation of BmDUOX and increased ROS production following N. bombycis infection. Immunofluorescence and antibody-blocking assays demonstrated that BmDUOX localizes to the plasma membrane and is essential for inhibiting spore adhesion and invasion. This study provides the first systematic evidence of DUOX-ROS-mediated anti-microsporidian immunity in B. mori, which may provide a theoretical basis for the future development of ROS-based disease control strategies in sericulture. Full article

Immune mediators are elevated due to carbon monoxide (CO) poisoning but their role in the development of neurological deficits is unknown. Circulating microparticles (MPs) are elevated in response to CO and correlate with the development of neurological complications. We hypothesized that interleukin (IL)-1β is carried by MPs and contributes to the development of neurological sequelae (NS). Blood-borne IL-1β in CO-poisoned patients is almost exclusively carried by MPs. Healthy humans have 0.8 ± 0.8 (n = 27) MPs/μL bearing IL-1β on the membrane surface. IL-1β-bearing MPs obtained from patients at the time of CO poisoning diagnosis who recover (Global Deterioration Score [GDS] = 1 at 1 month) numbered 35 ± 12/μL (n = 27, p < 0.001 vs. control) and patients who sustained NS (GDS > 1 at 1 month) had 75 ± 38/μL (n = 27; p < 0.001 vs. control and CO-recovered groups). Twice as many MPs carry IL-1β cargo as express surface-bearing IL-1β. The concentration is higher post-CO but does not correlate with NS. Those with NS have 43.8 ± 42.0 pg IL-1β /10⁶ MPs, and those with GDS = 1 have 33.0 ± 32.0 pg/10⁶ MPs, versus controls 5.4 ± 0.3 pg/10⁶ MPs, p < 0.001. In a murine CO model, MPs IL-1β cargo follows similar proportions to humans. Pharmacologic blockade of IL-1β using an IL-1 receptor antagonist or neutralizing anti-IL-1β antibody inhibited neuroinflammation and preserved neurological function. Results demonstrate that brain-derived MPs liberated via the glymphatic system to the peripheral circulation activate neutrophils which are the prime generators of IL-1β-bearing MPs that maintain a cycle of neuroinflammation. Targeting IL-1β disrupts MP-mediated inflammation. Full article

Background: Chronic autoimmune thyroiditis (CAT) is characterized by persistent autoimmune activity and increased oxidative stress, which may contribute to thyroid follicular injury and disease progression. Photobiomodulation (PBM) has shown potential beneficial effects on thyroid function and autoimmunity; however, its independent effect on systemic antioxidant status, particularly serum glutathione (GSH), has not been established. This study aimed to evaluate the effect of thyroid-directed PBM on serum GSH concentrations and thyroid-related outcomes in treatment-naïve euthyroid women with CAT. Methods: This prospective, non-randomized, open-label, parallel-group comparative interventional study included 50 treatment-naïve euthyroid women with CAT. Participants were allocated to receive either thyroid-directed transdermal PBM (n = 25) or selenium plus vitamin D supplementation (n = 25). The primary outcome was the change in serum GSH concentration. Secondary outcomes included changes in thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), anti-thyroid peroxidase antibodies (anti-TPO), anti-thyroglobulin antibodies (anti-Tg), thyroid volume, and anthropometric parameters. Assessments were performed at baseline (T0), after the intervention period (T1), and three months after intervention completion (T2). Results: A significant time × group interaction was observed for serum GSH concentrations (F = 19.101, p < 0.0001). Significant interactions were also observed for anti-TPO (F = 7.513, p = 0.001), anti-Tg (F = 7.389, p = 0.002), and thyroid volume (F = 13.081, p < 0.0001). In the PBM group, GSH increased from baseline to T1 and remained higher at T2, while TSH, anti-TPO, anti-Tg, and thyroid volume decreased, and FT3 and FT4 increased. No significant longitudinal changes in GSH or thyroid autoantibodies were observed in the supplementation group. No participant in the PBM group required levothyroxine (LT4) initiation during follow-up, whereas 24% of participants in the supplementation group initiated LT4 therapy at T1, with some requiring dose escalation by T2. Conclusions: Thyroid-directed PBM was associated with improved systemic GSH status and favorable changes in thyroid autoimmunity, thyroid function parameters, and thyroid volume compared with selenium plus vitamin D supplementation in treatment-naïve euthyroid women with CAT. These findings suggest that modulation of oxidative stress may represent one potential biological pathway underlying the observed effects of PBM. Larger randomized controlled studies with longer follow-up are required to confirm these findings and define the clinical role of PBM in autoimmune thyroid disease. Full article

Phosphorylated ACC (pACC), a downstream effector of the LKB1/AMPK pathway, may support tumor bioenergetics and exert a tumor-promoting role in glioblastoma (GBM). In the randomized REGOMA trial, pACC expression was associated with improved overall survival (OS) in GBM patients treated with regorafenib, but its validity in large cohorts is unclear. This study aimed to characterize pACC and phosphorylated AMPK (pAMPK) expression in a real-world GBM cohort and to assess their prognostic and predictive value in patients receiving second-line regorafenib or fotemustine/lomustine. In this retrospective, multicenter translational study, pACC and pAMPK were assessed by immunohistochemistry on FFPE tumor sections from 174 IDH-wild-type GBM patients treated with regorafenib (n = 84) or fotemustine/lomustine (n = 90). Staining was performed with a validated anti-pACC monoclonal antibody and quantified by digital pathology. Survival analyses included univariable and multivariable Cox proportional hazards models, with interaction testing. pACC and pAMPK were expressed in 85.6% and 95.4% of samples, respectively, with heterogeneous spatial patterns. Neither marker was significantly associated with OS in the univariable analyses, and neither retained independent prognostic value in multivariable analysis. Regorafenib was associated with significantly longer OS than alkylating agents (10.4 vs. 6.3 months; p = 0.0021). However, the treatment-by-pACC interaction test was not statistically significant (adjusted p = 0.610), providing no formal evidence of a differential treatment effect by pACC status. Although pACC-positive expression was enriched among patients experiencing longer overall survival under regorafenib, formal treatment-by-biomarker interaction was non-significant. These exploratory findings indicate that pACC is not an established predictive biomarker and warrant prospectively powered evaluation. Full article

Background: Arterial hypertension (HTN) is associated with accelerated vascular aging, cerebral microvascular injury, and cognitive decline. Anti-NR2/GluN2 (NR2) antibodies may be related to N-methyl-D-aspartate receptor (NMDAR)-mediated neuronal-ischemic injury, although their clinical significance in HTN requires further clarification. Objective: The aim of this study was to evaluate cross-sectional associations between arterial stiffness assessed by the cardio-ankle vascular index (CAVI), serum NR2 antibody levels, and cognitive performance assessed by the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE) in patients with essential HTN and controls. Methods: This single-center study included 175 adults aged 40–70 years: 128 patients with essential HTN and 47 controls. The median age was 58 [54; 66] years in the HTN group and 55 [47; 62] years in controls (p = 0.06). Men accounted for 52 patients (40.6%) in the HTN group and 14 participants (30.0%) in the control group (p = 0.22). Arterial stiffness was assessed using CAVI. Serum NR2 antibody levels were measured by enzyme-linked immunosorbent assay. Cognitive status was evaluated using MoCA and MMSE. Between-group comparisons, correlation analysis, and exploratory classification modeling were performed. Results: Patients with HTN had higher CAVI values than controls (8.3 [7.3; 9.4] vs. 7.3 [6.9; 7.9]; p = 0.001). Cognitive impairment was more frequent in hypertensive patients by both MoCA (52.3% vs. 27.7%; p = 0.003) and MMSE (48.7% vs. 28.3%; p = 0.01). NR2 antibody levels were higher in HTN (1.6 [1.15; 2.62] vs. 1.33 [1.02; 1.84] ng/mL; p = 0.03). CAVI inversely correlated with MoCA and MMSE scores. Conclusions: CAVI was higher in patients with HTN and showed modest inverse associations with cognitive scores. NR2 antibody levels were also higher in HTN; however, their relationship with cognitive impairment should be interpreted as exploratory and hypothesis-generating. Further longitudinal studies with neuroimaging are required to determine the clinical and prognostic significance of these findings. Full article

Avian infectious bronchitis virus (IBV) is widely distributed worldwide and causes substantial economic losses to the poultry industry. Because IBV undergoes frequent mutation, prevention and control of infection remain challenging. Immunization is an important measure for the prevention and control of IB. Therefore, there is an urgent need for a rapid, sensitive, specific, and convenient method for the detection of antibodies against IBV. In this study, we firstly developed an indirect colloidal gold immunochromatographic strip for the rapid detection of antibodies against IBV based on a conserved epitope peptide. The recombinant epitope peptide recognized by N2D5 monoclonal antibody (mAb) against the N protein of IBV was expressed as a GST fusion protein (GST-N2D5) based on the conserved antigenic epitope previously identified in our laboratory. Colloidal gold-labeled GST-N2D5 was used as the detection reagent to generate visual signals. Rabbit anti-chicken IgY and mouse anti-GST mAb were immobilized on the nitrocellulose membrane as the test line (T line) and control line (C line), respectively. The optimal pH and optimal protein concentration for conjugation of gold nanoparticles (AuNPs) with GST-N2D5 were pH 8.5 and 72 µg/mL, respectively. Specificity was evaluated using common avian pathogens, and no cross-reactivity was observed. The detection limit of the strip for IBV-positive serum was 1:180. In addition, the assay showed good reproducibility and stability, and results could be observed within 5 min without any specialized equipment. Clinical chicken serum samples were tested using both the developed strip and an enzyme-linked immunosorbent assay (ELISA), and the strip showed high agreement with the ELISA. In conclusion, the established immunochromatographic strip is rapid, sensitive, specific, and easy to operate, and therefore has potential as an on-site tool for the rapid detection of antibodies against IBV, particularly in resource-limited settings. Full article

Background/Objectives: Classical swine fever (CSF) and pseudorabies (PR), caused by classical swine fever virus (CSFV) and pseudorabies virus (PRV) respectively, are economically significant viral diseases worldwide that severely compromise swine health and constrain international trade. Previously, we generated a recombinant PRV (rPRVTJ-UL44-E2) expressing the CSFV E2 protein that elicited rapid E2-specific antibody responses in rabbits as early as 7 days post-immunization (dpi). However, its immunogenicity and protective efficacy in pigs remain uncharacterized. In this study, we evaluated the protective performance of rPRVTJ-UL44-E2 in pigs via needle-free immunization. Methods: Pigs (n = 5) received a prime immunization with 10⁷ median tissue culture infective doses (TCID₅₀) of rPRVTJ-UL44-E2 via needle-free immunization, followed by a boost immunization with the same dose at 21 dpi, and were then challenged with 10⁵ TCID₅₀ of the virulent CSFV Shimen strain (CSFV-SM) at 33 dpi. Results: Pigs immunized with rPRVTJ-UL44-E2 developed E2-specific antibodies (blocking rates > cutoff value (40%) at 25 dpi) and gB-specific antibodies that were detectable as early as 7 dpi, with anti-CSFV neutralizing antibody titers comparable to those induced by the C-strain vaccine and anti-PRV neutralizing antibody titers also reaching detectable levels at 28 dpi, whereas no specific antibodies were detected in the DMEM control group. All pigs immunized with rPRVTJ-UL44-E2 and C-strain survived the lethal CSFV challenge with no clinical signs or detectable viremia. In contrast all DMEM control pigs succumbed to infection within 9 days post-challenge (dpc). Conclusions: These findings demonstrate that needle-free delivery of rPRVTJ-UL44-E2 confers complete protection against lethal CSFV challenge in pigs. Full article

Anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis is a severe autoimmune neurological disorder characterized by pathogenic antibodies against the NMDAR. A systematic protein profiling approach is warranted to identify biomarkers capable of predicting disease status. An Olink proximity extension assay (PEA) profiled 91 inflammation-related proteins from anti-NMDAR encephalitis patients. Disease severity or prognosis were assessed by CASE score or mRS score at 6-month follow-up. Patients were stratified into distinct molecular clusters using unsupervised clustering. Logistic regression models incorporating selected biomarkers were developed to predict disease severity and prognosis, followed by absolute quantification using ELISA. Patients were classified into four consensus clusters. Clusters 1 and 2 corresponded to the mild group, while Cluster 3 represented the severe group, consistent with CASE score above 6. Cluster 4 showed heterogeneous clinical features. Elevated serum levels of IL-10, IL-6, and SIRT2, as well as increased CSF levels of CXCL10, CXCL11, and MMP10, were positively associated with severe disease. Conversely, several proteins including LTA and CCL11, CCL8, TGFB1, CXCL6 were associated with severe disease or unfavorable 6-month outcomes. A logistic regression model combining serum CXCL6 and CCL11 with CSF MMP10 achieved an area under the curve (AUC) of 0.95 for predicting disease severity. Serum CCL11 alone showed predictive value for 6-month prognosis, with an AUC of 0.79. These findings delineate distinct protein signatures associated with clinical heterogeneity of anti-NMDAR encephalitis. Prediction models incorporating multiple biomarkers may provide an approach for disease severity stratification and prognosis forecast. Full article

Healthcare workers (HCWs) and medical providers are regularly exposed to a wide range of infectious diseases in the course of their duties. This occupational risk is significant in the context of highly contagious infections such as measles, which can spread rapidly in healthcare institutions. This study aimed to assess the seroprevalence of protective anti-measles and anti-rubella IgG antibodies and factors influencing immunity among HCWs across all 28 districts in Bulgaria. Methods: A total of 1854 individuals, including 540 (29%) doctors and 1314 (71%) medical specialists from all 28 districts in Bulgaria, were screened for protective immunity against measles and rubella. Serum samples were analyzed for the presence of protective IgG antibodies by ELISA (Enzyme-Linked Immunosorbent Assay) using commercial EUROIMMUN Anti-Measles/Anti-Rubella Virus IgG ELISA kits. According to the manufacturer’s instructions, the results were interpreted semi-quantitatively as positive, negative, and equivocal. Results: Anti-measles protective IgG antibodies were detected in 86.1% of participants for measles and in 95.2% for rubella. Our study found a statistically significant difference when analyzing demographic factors (age) for measles: the samples from older participants (over 50-year-old persons) were characterized by higher immunity levels; staff working in non-infectious-disease wards (n+ = 95.7%) were more frequently positive for rubella IgG antibodies compared to staff employed in infectious wards; and region locations varied for both groups. Gender and professional roles were not significant predictors. Conclusions: HCWs are at a greater risk of contracting infections than the general public because they have contact with sick patients or infectious material. Their vaccination or IgG immunity status must be strictly monitored, especially to limit the spread of nosocomial infections in hospital settings. Full article

Background/Objectives: A reactive anti-HCV antibody result requires confirmatory testing because seropositivity does not necessarily indicate active hepatitis C virus (HCV) infection. Although anti-HCV signal intensity may provide clinically useful information, it remains underutilized, particularly in low-reactivity ranges where diagnostic uncertainty is substantial. This study evaluated the diagnostic performance of anti-HCV signal-to-cutoff (S/Co) values and aimed to define a clinically meaningful uncertainty interval. Methods: In this retrospective study, 565,726 anti-HCV test results were screened, and the analysis was performed within the anti-HCV reactive cohort (≥1.0 S/Co; n = 2950), comprising 1581 patients with true HCV infection and 1369 without infection. Infection status was assigned using a uniform virological reference standard, every case being supported by at least one documented positive HCV-RNA PCR result. Receiver operating characteristic (ROC) analysis was used to assess discrimination, and multivariable logistic regression to model the probability of true infection. Results: Anti-HCV signal intensity discriminated true infection well across the reactive cohort (AUC 0.991), but less within the diagnostic uncertainty interval (1.00–4.99 S/Co; AUC 0.832), where only 5.7% of reactive results represented true infection. A Youden-optimal threshold of 4.65 S/Co provided >95% sensitivity, specificity and positive predictive value in the reactive cohort. The probability of true infection rose steeply with signal level, and each doubling of the S/Co value increased the odds of infection 23–fold. No threshold within the uncertainty interval raised the positive predictive value above 58.2%. Restricting confirmatory testing to values above 2.50 S/Co would avoid 41.7% of confirmatory tests while missing 1.96% of true infections. Conclusions: Anti-HCV signal intensity is strongly associated with the probability of true infection, but a single fixed cut-off is insufficient for clinical interpretation. Graded, signal-based interpretation may improve diagnostic accuracy, clarify low-level reactivity, and reduce unnecessary confirmatory testing. Full article

Peste des petits ruminants virus (PPRV) causes a highly fatal disease that severely impacts small ruminant production and global food security. This study aimed to develop a rapid, user-friendly colloidal gold immunochromatographic test strip for detecting PPRV-specific antibodies using a double-antigen sandwich format. Bioinformatic analysis using DNASTAR Protean was performed to predict candidate antigenic regions in the PPRV H and N proteins. Three predicted candidate regions from each protein were selected and incorporated into the design of the recombinant fusion antigen PPRV-H₃N₃EP. The recombinant antigen was expressed in E. coli, purified, and refolded to obtain a final concentration of 8.52 mg/mL. The strip was assembled with colloidal gold-labeled fusion protein as the detection probe and unlabeled protein coated on the test line, plus an independent mouse IgG/goat anti-mouse IgG control system. Performance evaluation showed that the results were readable within 10–15 min. The strip showed satisfactory analytical sensitivity and cross-reactivity performance, consistent qualitative results in within-batch repeatability testing, and preliminary short-term storage stability. In a comparative evaluation using sheep serum samples and a commercial competitive enzyme-linked immunosorbent assay (ELISA) kit, the overall agreement reached 97.9%. Collectively, the constructed PPRV-H₃N₃EP antigen enabled a simple, rapid, and reliable strip assay suitable for field detection of PPRV antibodies and post-vaccination monitoring, while also providing a methodological reference for developing antibody tests for other pathogens. Full article

Background/Objectives: Antibody selection is critical for advancing pretargeted PET imaging toward clinical translation. This study directly compared two clinically approved anti-HER2 antibodies—trastuzumab and pertuzumab—within an identical pretargeting system, utilizing the specific chemical ligation between tetrazine and trans-cyclooctene (TCO) via the inverse electron-demand Diels–Alder (IEDDA) cycloaddition. Methods: In HER2-positive SKOV3 tumor-bearing mice, TCO-conjugated antibodies were administered 1–13 days prior to injection of a fluorine-18-labeled tetrazine probe ([¹⁸F]PEG₁₂-Tz). Results: Both strategies enabled high-contrast imaging, overcoming the kinetic mismatch between slow-clearing antibodies and the short-lived ¹⁸F isotope. Distinct profiles were observed: pertuzumab-TCO yielded higher tumor uptake and a broader imaging window (3–13 days), whereas trastuzumab-TCO resulted in lower uptake and a narrower window (1–5 days). These differences are not affinity-driven, as both conjugates showed similar Kd values (~11–14 nM). Instead, pertuzumab-TCO’s superiority stems from a dual mechanism: (1) slower cellular internalization (65.1% vs. 94.0% at 60 min) preserves surface TCO for click reaction; and (2) markedly slower blood clearance (t_1/2β = 285.9 h vs. 106.0 h) ensures sustained bioavailability and tumor extravasation. Conclusions: This head-to-head evaluation demonstrates that epitope-dictated internalization and clearance are decisive parameters for antibody selection, providing a mechanism-based framework for optimizing pretargeted imaging. Full article

Background: Idiopathic pulmonary fibrosis (IPF) is closely associated with fibroblast proliferation, macrophage polarization, and the accumulation of extracellular matrix (ECM). Targeting CSF-1R can rebalance macrophages, reduce ECM deposition, and block pro-fibrotic signaling. Methods: A Fab fragment targeting CSF-1R was screened via phage display. After sequence optimization, it was constructed into an IgG1 antibody (BC006). In vitro activity, domain binding, and signaling blockade were investigated, and in vitro safety indicators were evaluated. Efficacy was assessed using an induced IPF organoid-on-a-chip and bleomycin-induced mouse model. In vivo safety evaluation was conducted in cynomolgus monkeys. Results: BC006 showed an EC₅₀ value of 226 ± 57 nM and a KD of 30 ± 2 nM. It specifically bound to the Ig4-5 domain of CSF-1R by inhibiting receptor dimerization without blocking ligand binding. It could dose-dependently inhibit the differentiation of monocytes into M2 macrophages and exert anti-IPF effects. In the induced IPF organoid-on-a-chip model, BC006 maintained lung barrier function and decreased α-SMA and Collagen I. It also improved lung function and attenuated the degree of fibrosis in the mouse model. Moreover, BC006 had no ADCC, CDC, cytokine release, or hemagglutination, and demonstrated favorable safety profiles in cynomolgus monkeys. Conclusions: BC006 is a novel anti-fibrosis antibody specifically targeting the CSF-1R Ig4-5 domain and offers a new therapeutic strategy for IPF. Full article

Bacteriophage technologies have evolved from classical cloning vectors into programmable platforms for genome engineering and molecular selection. Phage display couples a surface-presented binding phenotype to its encoding genotype, enabling iterative selection, sequence recovery, and optimization of peptides, antibody fragments, and other protein binders. This review links phage morphology, genome organization, infection strategy, host defense, and engineering method to practical platform choice. It compares λ, N15, M13, and T7 systems; examines biopanning bias and candidate developability; and evaluates artificial intelligence-assisted, sequencing-guided, and structure-guided workflows. Vaccine applications are considered alongside constraints arising from anti-phage immunity, antigen density, route of administration, and repeat dosing. Progress will depend on experimentally validated closed-loop workflows that integrate library design, selection, high-throughput analytics, structural characterization, and early manufacturability assessment. Full article

Background: Sex-related differences in SARS-CoV-2 viral susceptibility, severity, and recovery are prevalent. Factors such as age and biological variation provide some explanation for immune response, yet the use of biological sex as a variable may limit understanding of underlying individual mechanisms related to endocrine–immune function involved in long-term immune memory. Endogenous sex hormone concentrations provide a means to assess the magnitude or durability of antibody persistence and disease recovery. Objective: This study examined salivary concentrations of 17β-estradiol and testosterone, as well as the number of weeks since prior SARS-CoV-2 viral infection. The study aimed to determine whether endogenous sex hormones contributed additional explanatory value to antibody persistence beyond biological sex. Methods: A cross-sectional study included 75 college students (63% female) who reported weeks since previous SARS-CoV-2 infection (M = 15.41, SD = 7.13), confirmed through a positive SARS-CoV-2 anti-N rapid antibody test. Participants provided saliva samples, which were tested for concentration of 17β-estradiol and testosterone. Hierarchical multiple regression analyses examined the effects of biological sex and endogenous sex hormones on the persistence of SARS-CoV-2 antibodies following natural infection. Results: 17β-estradiol was the strongest positive predictor of SARS-CoV-2 antibody persistence (β = 0.63, p < 0.001). Departing from previous findings, biological sex was not a significant predictor of antibodies targeting the SARS-CoV-2 N protein. Conclusions: Findings underscored the role of estradiol on immune recovery in a healthy young adult population. Individual hormone variation appears more informative than sex classification for understanding antibody persistence and immune response. Full article