Search Results (3,012)

Background/Objectives: While tick-borne encephalitis virus (TBEV) is genetically relatively conserved, the significant antigenic divergence between its main circulating subtypes hinders the development of broadly effective antiviral treatments and vaccines. Current inactivated TBEV vaccines offer limited cross-protection against heterologous strains, as evidenced by cases among vaccinated individuals in endemic regions. The aim of this study was to design a candidate mRNA vaccine and evaluate the breadth of protective immunity it elicits. Methods: Ten candidate mRNA-PrM/E-LNP vaccines were comparatively evaluated for immunogenicity and protective efficacy in BALB/c mice. Immunogenicity was assessed by measuring antigen-specific IgG titers via ELISA and neutralizing antibody titers against a panel of TBEV strains using a virus-neutralization test. Protective efficiency was determined in a lethal challenge model, where immunized mice were challenged with one of seven distinct TBEV strains. Results: Vaccination with all tested mRNA-PrM/E-LNP candidates conferred 100% survival in mice following a lethal challenge with each of the seven TBEV strains (100 LD₅₀). The construct mRNA-PrM/E—Krasny Yar-8 demonstrated the highest immunogenicity, inducing antigen-specific antibodies with a geometric mean titer (GMT) of 1:6625, as well as the broadest virus-neutralizing activity against both homologous and heterologous TBEV strains in vitro. Conclusions: The mRNA platform represents a promising strategy for developing TBEV vaccines, demonstrating high immunogenicity and cross-protective efficacy against diverse viral strains. Full article

Background: Hepatitis B vaccination is the most effective strategy for preventing chronic hepatitis B virus (HBV) infection; however, interindividual variability in vaccine-induced antibody responses remains a significant challenge in the field. Innate immune components, particularly lectin complement pathway proteins such as mannose-binding lectin (MBL), mannose-associated serine protease 1 (MASP-1), and mannose-associated serine protease 2 (MASP-2), may contribute to this variability in outcomes. This study aimed to evaluate the association between serum MBL, MASP-1, and MASP-2 levels, birth weight, and humoral response to hepatitis B vaccination in infants. Methods: This single-center prospective observational study included 37 term infants who received hepatitis B vaccinations at birth, 1 month, and 6 months of age according to the national immunization schedule. Venous blood samples were collected at month 6, before, and month 7 after the 3rd vaccine dose. Serum MBL, MASP-1, MASP-2, and antiHB levels were measured using commercial ELISA and chemiluminescence assays. Data were analyzed using non-parametric statistical tests and Spearman’s correlation analysis. Results: AntiHB levels increased significantly following vaccination (median Pre-3rdVac: 125.8 mIU/mL; Post-3rdVac: 609.7 mIU/mL; p < 0.001). MASP-1 concentrations also showed a significant Post-3rdVac increase (median Pre-3rdVac: 809.52 ng/mL; Post-3rdVac: 1133.93 ng/mL; p = 0.019). Birth weight was positively correlated with both MASP-1 levels (r_s = 0.492, p = 0.004) and changes in MASP-1 concentrations (r_s = 0.524, p = 0.002) after the third dose. In addition, MASP-1 levels were positively associated with antiHB levels (r_s = 0.385, p = 0.030) and Post-3rdVac antiHB titers (r_s = 0.493, p = 0.004). In contrast, serum MBL and MASP-2 concentrations were not significantly associated with antiHB levels before or after vaccination. Conclusions: MASP-1, but not MBL or MASP-2, is associated with the magnitude of the antibody response to hepatitis B vaccination in infants. These findings suggest that specific components of the lectin pathway may influence vaccine-induced immunity, independent of MBL. Further large-scale studies incorporating genetic and functional analyses are warranted to clarify the mechanisms by which lectin pathway proteins shape hepatitis B vaccine response. Full article

Prevalence of LPS in Gram-negative bacterial udder infections determines mastitis severity and disease prognosis. This pilot study explores the notion that milk-soluble (s) LPS/IgG complex levels in dairy cows link mastitis severity to intramammary Gram-negative infections during early lactation. Milk, within a single herd, was analysed from (i) 34 early lactating cows with acute mastitis and (ii) milk selected from peak lactation cows displaying either healthy (SCC < 100 × 10³ cells/mL, n = 146) or subclinical mastitis (SCC > 150 × 10³ cells/mL, n = 135) characteristics. Milk was assessed for (i) sLPS/IgG using an “in-house” ELISA, (ii) udder inflammation using LDH activity, and (iii) bacterial presence applying on-farm and standard microbiological laboratory techniques. Mean milk sLPS/IgG absorbances in acute mastitis cows were higher than those detected in healthy and subclinical mastitis cows, with mean differences of 0.35 (95% CI, 0.28 to 0.42) and 0.36 (95% CI, 0.28 to 0.44), respectively. On day 1 of acute mastitis, sLPS/IgG levels in milk containing only Gram-positive bacteria ranged from OD 0.04 to 0.14 (median = 0.1). In contrast, sLPS/IgG levels ranging from OD 0.27 to 1.42 (median = 0.58) and from 0.02 to 1.67 (median = 0.21) were detected in milk containing only Gram-negative bacteria or both Gram-negative and Gram-positive bacteria (i.e., polymicrobial), respectively. Furthermore, differential milk sLPS/IgG absorbance profiles (observed during the testing period days 1–3) were observed in cows with acute mastitis caused by Gram-positive, Gram-negative or polymicrobial infections. Our preliminary findings support the notion that milk sLPS/IgG complexes provide a link between mastitis severity and intramammary Gram-negative infections in dairy cows during early lactation. Full article

Bovine tuberculosis is a zoonotic infectious disease of cattle caused by the bacterium Mycobacterium bovis. In adult cattle, transmission is mainly via the respiratory route, whereas, in young calves, oral infection is also common. Congenital tuberculosis is rare. The purpose of this study was to describe in utero infection of a bovine stillbirth. The fetus was necropsied and tissue samples were processed for histopathology, bacteriology and PCR; a sample of the isolated strain was genotyped using spoligotyping. The whole herd was tuberculin skin tested and the dam’s serum was also assessed for the presence of antibodies against bovine tuberculosis with indirect ELISA. The macroscopic findings in different organs were consistent with tuberculosis. The histopathology demonstrated typical granulomatous lesions in the liver, spleen, hepatic and mediastinal lymph nodes. Acid-fast bacilli were observed in the smears stained using the Ziehl–Neelsen method. The colonies isolated were PCR-positive for IS6110 and the spoligotype corresponded to SB0140. The dam of the stillborn was positive for indirect ELISA and reacted to a single caudal skin test with bovine tuberculin. The fetal infection in utero with Mycobacterium bovis was confirmed through necropsy, histopathology and bacteriology, reinforcing the importance of testing young animals. Full article

The fish liver, as the main detoxification organ, is highly susceptible to xenobiotic exposure, often resulting in various hepatopathies. The cytochrome P450 system plays a central role in xenobiotic metabolism, with cytochrome P450 reductase (CYPOR) supplying the electrons required for CYP enzyme activity. This study aimed to evaluate the relationship between the ecological state of a reservoir and fish health, including CYPOR levels, through hematological, bacteriological, and histological analyses. Samples of water and fish were collected from 12 littoral sites of Lake Ladoga. A total of 1360 specimens of fish from carp (Cyprinidae) and perch (Percidae) families were examined. For histological examination and CYPOR level determination, we selected 40 specimens using a blind randomization method. This sample size was sufficient for statistical analyses. Hematological smears were stained with azure eosin; bacteriological cultures were grown on multiple media; liver samples were stained with hematoxylin and eosin and Sudan III. CYPOR levels in liver homogenates were measured by ELISA-test. Physical and hydrochemical analyses indicated a high pollution level in the littoral zones. Isolated bacterial species were non-pathogenic but exhibited broad antibiotic resistance. Hematological evaluation revealed erythrocyte vacuolization and anisocytosis. Histological analysis showed marked fatty degeneration in hepatocytes, indicating toxic damage. CYPOR concentrations ranged from 0.3–0.4 ng/mL in healthy fish to 5–6 ng/mL in exposed specimens, showing strong correlation between environmental influence and enzyme activity. These findings demonstrate the potential of CYPOR as a sensitive biomarker for biomonitoring programs. The integrated methodological approach provides a model for assessing aquatic ecosystem health and identifying zones requiring priority remediation. Full article

Reticuloendotheliosis virus (REV) is an immunosuppressive virus in poultry that can cause acute reticular neoplasms, chronic lymphoid tumors, stunting syndrome, and secondary infections. In many countries, the lack of effective vaccines has resulted in a high prevalence of REV infections and substantial economic losses. Enzyme-linked immunosorbent assay (ELISA)-based antibody detection is an important tool for monitoring the REV prevalence in poultry farms. ELISA coating antigens generally consist of either whole virus or viral protein; however, most commercially available REV antibody ELISA detection kits use whole virus as the coating antigen, which limits their applicability in certain diagnostic and research settings. In this study, the gp90 protein from a dominant REV strain was expressed and purified using 293F suspension cell eukaryotic expression system. Using recombinant gp90 protein as the coating antigen, an indirect ELISA for detecting gp90 antibodies (gp90-ELISA) was developed. After optimization, the optimal conditions were as follows: coating antigen concentration of 4 µg/mL with overnight incubation at 4 °C; blocking with 5% skim milk at 37 °C for 1.5 h; serum dilution of 1:200 with incubation at 37 °C for 45 min; secondary antibody dilution of 1:1000 with incubation at 37 °C for 30 min; and color development using TMB substrate at room temperature in the dark for 10 min. The cut-off value was defined as an OD₄₅₀ ≥ 0.22 for positive samples and <0.22 for negative samples. The developed gp90-ELISA specifically detected REV-positive sera at a maximum serum dilution ratio of 1:3200. Intra- and inter-assay variation coefficients were ≤10%, indicating that the gp90-ELISA had good specificity, sensitivity, and reproducibility. Laboratory serum testing showed that the gp90-ELISA successfully detected sera from chickens immunized with the gp90 protein or infected with REV. Furthermore, analysis of clinical serum samples demonstrated 100% concordance between the gp90-ELISA results and a commercial whole-virus-coated ELISA kit. These results indicate that the gp90-ELISA is a reliable supplementary method to whole-virus-coated ELISA and has potential utility in disease surveillance and evaluation of immune responses. Full article

Pathogens such as Toxoplasma gondii, lentiviruses (e.g., CAE), Hypoderma spp., Neospora caninum, Mycoplasma spp., and pestiviruses are important for goat farming in Lithuania; however, data on their prevalence remain limited. To address this gap, a multi-pathogen study was conducted between 2021 and 2024 using selected ELISA kits (ID.vet, Innovative Diagnostics, France). A total of 380 blood samples were collected from 30 goat herds across different regions of Lithuania; the sample size varied depending on the pathogen. Serum samples were tested for antibodies, and seroprevalence was calculated for each pathogen. The highest seroprevalence was detected for T. gondii (38.9%, 143/368) and CAE virus (19.5%, 74/380). Antibodies to Mycoplasma spp. (0.3%, 1/368), Hypoderma spp. (3.8%, 7/184), and N. caninum (0.5%, 2/368) were detected only sporadically, while no antibodies to Border disease virus or Q fever were identified. Mixed infections were found in 7.6% of samples. Chi-square analysis showed that co-infections with toxoplasmosis and CAE occurred more frequently than expected (χ² = 19.05, p < 0.001). Herd size was significantly associated only with CAE seroprevalence (χ² = 7.913, df = 1, p < 0.05). Overall, toxoplasmosis and CAE were identified as the most epidemiologically relevant infections in the Lithuanian goat population. Full article

Circulating irisin, a myokine implicated in energy expenditure and adipose tissue regulation, has been increasingly studied as a potential biomarker of metabolic dysfunction. This study evaluated the relationship between serum irisin and metabolic indices, including the atherogenic index of plasma (AIP), the lipid accumulation product (LAP), and hypertriglyceridemic-waist (HTGW) phenotype in individuals with prediabetes (PreDM) and newly diagnosed type 2 diabetes mellitus (T2DM). A total of 138 participants (48 PreDM, 90 T2DM) were assessed for anthropometric, glycemic, and lipid parameters. Serum irisin levels were measured by enzyme-linked immunosorbent assay (ELISA) and correlated with insulin resistance indices (Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), Quantitative Insulin Sensitivity Check Index (QUICKI)), glycemic control (glycosylated hemoglobin A1c (HbA1c)), and composite lipid markers (total triglycerides-to-high-density lipoprotein cholesterol (TG/HDL-C)). Group differences were evaluated using non-parametric tests; two-way ANOVA assessed interactions between phenotypes and markers; multiple linear regression (MLR) and logistic regression models explored independent associations with metabolic indices and HTGW; receiver operating characteristic (ROC) analyses compared global and stratified model performance. Serum irisin was significantly lower in T2DM than in PreDM (median 140.4 vs. 230.7 ng/mL, p < 0.0001). Irisin levels remained comparable between males and females in both groups. Post hoc analysis shows that lipid indices and irisin primarily distinguish HTGW phenotypes, especially in T2DM. In both groups, irisin correlated inversely with HOMA-IR, AIP, and TG/HDL-C, and positively with QUICKI, indicating a possible compensatory role in early insulin resistance. MLR analyses revealed no independent relationship between irisin and either AIP or LAP in PreDM, while in T2DM, waist circumference remained the strongest negative predictor of irisin. Logistic regression identified age, male sex, and HbA1c as independent predictors of the HTGW phenotype, while irisin contributed modestly to overall model discrimination. ROC curves demonstrated good discriminative performance (AUC = 0.806 for global; 0.794 for PreDM; 0.813 for T2DM), suggesting comparable predictive accuracy across glycemic stages. In conclusion, irisin levels decline from prediabetes to overt diabetes and are inversely linked to lipid accumulation and insulin resistance but do not independently predict the HTGW phenotype. These findings support irisin’s role as an integrative indicator of metabolic stress rather than a stand-alone biomarker. Incorporating irisin into multi-parameter metabolic panels may enhance early detection of cardiometabolic risk in dysglycemic populations. Full article

Systemic Lupus Erythematosus (SLE) and primary Sjögren’s Disease (SjD) are autoimmune diseases characterized by the presence of autoantibodies that lead to damage in healthy tissues. The production of autoantibodies requires the activation and differentiation of B-lymphocytes into plasma cells. To achieve this effect, BAFF (B-lymphocyte activating factor), APRIL (A proliferation-inducing ligand), and their receptors are key factors. BAFF is a cytokine recognized by BAFF-R (BAFF receptor), which is increased and related to disease activity in both SLE and SjD patients. The H159Y mutation (rs61756766) in the gene encoding the BAFF-R, TNFRSF13C (Tumor Necrosis Factor Receptor Superfamily) has been shown in vitro to cause receptor hyperactivation via the NF-κB2 pathway. This study evaluated the frequency of this variant in a western Mexican population and its association with the risk of developing SLE and SjD. Genotypes of the TNFRSF13C H159Y (rs61756766) variant were determined by PCR-RFLP assay. sBAFF levels were measured by ELISA. The study included 300 SLE patients, 110 SjD patients, and 300 healthy subjects (HS). HS were in Hardy–Weinberg equilibrium. The data distribution was assessed using the Kolmogorov–Smirnov test. Group comparisons were conducted using the Chi-square test, Fisher’s exact test, or the Mann–Whitney U test, as appropriate. A p-value of <0.05 was considered statistically significant. In the Mexican population, allelic and genotypic distribution frequencies of the H159Y variant (rs61756766) were similar between SLE patients and HSs, while the variant was not found in SjD patients. SLE patients carrying the heterozygous CT genotype showed a trend toward higher soluble BAFF (sBAFF) levels than wild-type genotype patients. This variant does not confer risk to SLE or SjD in the Mexican population. However, the heterozygous genotype may be associated with high levels of sBAFF in SLE patients. Full article

Background: Alzheimer’s disease (AD), a progressive brain disorder, is the most common form of dementia and necessitates the development of effective intervention strategies. Ginseng-Natto composite fermentation products (GN) have demonstrated beneficial bioactivities in mouse models of AD; however, the underlying mechanism of action through which GN ameliorates AD requires further elucidation. Methods: Mice received daily intragastric administration of low- or high-dose GN for 4 weeks, followed by intraperitoneal injection of scopolamine to induce the AD model. The pharmacological effects of GN were systematically evaluated using the Morris water maze test, ELISA, and H&E staining. To further investigate the underlying mechanisms, 16S rRNA gene sequencing and metabolomics were employed to analyze the regulatory effects of GN on the gut–brain axis. Additionally, Western blotting was performed to assess the impact of GN on blood–brain barrier (BBB) integrity. Results: GN intervention significantly ameliorated cognitive deficits and attenuated neuropathological injury in AD mice, restoring the brain levels of acetylcholine (ACh), acetylcholinesterase (AChE), superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) to normal ranges. GN reshaped the gut microbiota by promoting beneficial bacteria and inhibiting pro-inflammatory strains. It also regulated key metabolic pathways related to amino acid and unsaturated fatty acid metabolism. This metabolic remodeling restored the compromised BBB integrity by upregulating tight junction proteins (ZO-1, Occludin and Claudin-1). Conclusions: Our findings demonstrate that GN ameliorates AD through a gut-to-brain pathway, mediated by reshaping the microbiota-metabolite axis and repairing the BBB. Thus, GN may represent a promising intervention candidate for AD. Full article

Background: Ulcerative colitis (UC) management relies on accurately assessing disease activity. Fecal calprotectin (FC) is a promising non-invasive biomarker, but method-specific differences in measurement can affect interpretation. Objective: To compare the performance of Calprest ELISA and DiaSorin Liaison CLIA in measuring FC concentrations and their correlation with endoscopic findings in UC. Methods: Stool samples from 40 UC patients were analyzed using both methods, with 138 samples collected across three clinical timepoints. Spearman’s correlation, Wilcoxon test, Bland–Altman analysis, and ROC curves were used to evaluate method agreement and diagnostic performance relative to Mayo endoscopic scores. Results: A total of 135 paired results showed strong correlation (ρ = 0.795, p < 0.001) but significant inter-method differences (p = 0.039). Liaison tended to yield higher FC values. ROC analysis established optimal cut-offs for detecting endoscopic remission and active disease: 47.95/69.55 µg/g (Liaison) and 65/125 µg/g (Calprest). Calprest demonstrated slightly better diagnostic accuracy. Conclusions: Both methods are reliable for monitoring UC activity. Calprest offers greater dynamic range, while Liaison excels in automation and speed. Method-specific thresholds should guide clinical interpretation to ensure accurate disease monitoring. Full article

Background: Despite the availability of a killed whole-virus (KV) vaccine, diarrhea caused by equine rotavirus group A (ERVA) remains a significant health concern for foals in the United States. The vaccine is administered to pregnant mares, with foals protected by passive transfer of colostral antibodies. However, KV-induced immunity is only partially protective and maternal antibody levels in foals are often low and wane rapidly. To address these limitations, we developed a mRNA-based ERVA vaccine encoding the highly conserved VP8* protein to evaluate whether it can provide improved immune protection. Methods: Pregnant mares (n = 12 per group) were immunized either at months 8 and 10 of gestation with the VP8* mRNA or at months 8, 9, and 10 of gestation with the KV. Serum samples were collected from mares before and after immunization and from their foals at ages 1, 35, and 49 days. Serum samples were tested by indirect ELISA for VP8*-specific relative antibody concentrations and relative concentrations were compared for effects of study group and sample-time using linear mixed-effects regression. To detect functional antibodies against ERVA, a virus neutralization titer assay was performed to compare titers between mares vaccinated with the mRNA vaccine (and their foals) and unvaccinated control mares (and their foals). Results: Mares vaccinated with VP8* mRNA had significantly (p < 0.05) higher antibody concentrations after foaling than mares in the KV group, and foals of VP8* mRNA-vaccinated mares had significantly (p < 0.05) higher concentrations through age 49 days than foals in the KV group. In addition, the VP8* mRNA vaccine elicited higher titers of ERVA-neutralizing antibodies against both G3 and G14 strains. Conclusions: Longer-lasting, higher concentrations of virus-neutralizing antibodies might provide superior duration of immunity to ERVA in foals from mares vaccinated with VP8* mRNA. Full article

Goose astrovirus (GoAstV) infection has become prevalent in major goose-producing regions, causing substantial economic losses to the industry. In this study, an indirect competitive ELISA (ic-ELISA) was developed based on a monoclonal antibody (mAb) targeting the GoAstV VP27 protein. The recombinant VP27 protein was expressed in E. coli and purified, followed by the generation of murine mAbs using the purified antigen. Through screening with GoAstV particles, mAb 3G11 exhibited strong immunoreactivity, which was further confirmed by Western blot and immunofluorescence assay (IFA). The ic-ELISA conditions were optimized as follows: GoAstV particle coating concentration of 10⁴ TCID₅₀ per well, 3G11 mAb dilution of 1:8000, and incubation times of 120 min for coating, 60 min for serum samples, and 60 min for mAb binding. The assay exhibited satisfactory performance in terms of sensitivity, specificity, and reproducibility. Using this method, serum samples collected from major goose farming areas in Shandong province were tested and showed an overall seropositivity rate of 11.7%. This study provided a reliable serological tool for detecting GoAstV-specific antibodies and would support future vaccine evaluation efforts. Full article

Background: In Bangladesh, a number of sex workers are involved in commercial sex work in different brothels in both legal and illegal settlements due to reasons such as lack of social support, depression, forced sex, abuse, violence, polyamory, being kidnapped, and unemployment. In this study, we tried to evaluate the demographic characteristics and prevalence of viral and sexually transmitted diseases (STDs) among the study population. Methods: A total of 250 female sex workers were interviewed and tested from the Daulatdia brothel of Rajbari district, Bangladesh, who had been working there for at least 1 month. Through questionnaires, demographic data were collected. Primarily, lateral flow immunoassay (LFIA) tests were used to investigate HCV (Hepatitis C Virus), HBV (Hepatitis B Virus), and Syphilis, which were reconfirmed using enzyme-linked immunosorbent assay (ELISA) in cases of positive results. Results: The mean age was 27.51 ± 6.69 years with a range of 18–50 years. Most of them (n = 243, 97.98%) had elementary knowledge of STDs. We determined that overall, 96 (38.40%) were positive for either of these diseases. Individually, 10 (4.00%), 18 (7.20%), and 68 (27.20%) were positive for HCV, HBV, and syphilis, respectively. Conclusions: Our observation indicates that females of all ages should be strictly protected from forced sex work. Current sex workers should be educated regarding the dangers and protective mechanisms of STDs. In addition, as a public health concern, regular clinical check-ups and STD associated diagnoses are necessary to ensure the safety of FSW from these highly infectious and concerning diseases. Due to their socio-economic condition, proper treatment and rehabilitation are highly recommended. Full article

Acinetobacter baumannii represents a critical-priority organism due to its multidrug resistance. The emergence of carbapenem-resistant strains poses a major clinical challenge, underscoring the urgent need for novel antibacterial agents with alternative mechanisms. As peptide nucleic acids (PNAs) have recently gained attention as antisense therapeutics, we aimed to validate their potential as novel antimicrobial strategies against multidrug-resistant A. baumannii. We synthesized a cell-penetrating peptide (CPP)–PNA conjugate targeting pdxA, an essential gene involved in vitamin B6 biosynthesis. Among several candidate genes tested, the pdxA-targeting PNA exhibited the strongest inhibitory activity, achieving complete growth suppression of A. baumannii at 1.56 μM. Although quantitative real-time polymerase chain reaction did not reveal significant reductions in pdxA transcript levels, ELISA quantification revealed an approximately 80% reduction in intracellular vitamin B6, indicating translational inhibition rather than mRNA degradation. The pdxA-targeting CPP–PNA showed negligible activity against other Gram-negative or Gram-positive species, indicating high target specificity; no detectable cytotoxicity in human cells was observed even at relatively high concentrations. CPP–PNA conjugates targeting pdxA interfere with vitamin B6 biosynthesis, leading to growth inhibition of A. baumannii. These findings support PNA as a promising antisense antimicrobial platform that inhibits multidrug-resistant A. baumannii by blocking vitamin B6 biosynthesis. Full article