Search Results (550)

Canine visceral leishmaniasis (CVL) is a major zoonosis that poses a growing challenge to public health services, as successful disease management requires sensitive, specific, and rapid diagnostic methods capable of identifying infected animals even at a subclinical level. The objective of this study was to evaluate the performance of the recombinant chimeric protein rMELEISH3 as an antigen in ELISA assays for the robust diagnosis of CVL. The protein was expressed in a bacterial system, purified by affinity chromatography, and evaluated through a series of serological assays using serum samples from dogs infected with Leishmania infantum. ROC curve analysis revealed a diagnostic sensitivity of 96.4%, a specificity of 100%, and an area under the curve of 0.996, indicating excellent discriminatory power. Furthermore, rMELEISH3 was recognized by antibodies present in the serum of dogs with low parasite loads, reinforcing the diagnostic potential of the assay in asymptomatic cases. It is concluded that the use of the recombinant antigen rMELEISH3 could significantly contribute to the improvement of CVL surveillance and control programs in endemic areas of Brazil and other countries, by offering a safe, reproducible and effective alternative to the methods currently recommended for the serological diagnosis of the disease. Full article

This study aimed to assess the emergence and/or re-emergence of Tick-borne Diseases (TBD) in Portugal by linking the hemoparasite burden in companion animals to vector-borne disease dynamics through a One Health approach. Between 2015 and 2024, 1169 clinically suspected animals with hemoparasite infections, treated at the Hospital Veterinário de Santarém (HVS), underwent serological confirmation for Rickettsia conorii, Babesia canis, Ehrlichia spp., and Haemobartonella spp. A total of 3791 serological tests (3.2 tests per animal) were performed and 437 animals tested positive for at least one of the four hemoparasites under investigation. From 2020 to 2024, tests nearly tripled from 894 to 2883, raising positive cases and prevalence from 29.5% to 39.9%, especially for rickettsiosis and hemobartonellosis, indicating an increased circulation of their vectors. A national vector surveillance initiative identified Hyalomma spp., Rhipicephalus sanguineus, Ixodes ricinus, and Dermacentor sp. as primary tick vectors in Portugal for the hemoparasites mentioned above and for other agents like arbovirus, such as Crimean-Congo Hemorrhagic Fever Virus (CCHFV) and tick-borne encephalitis virus (TBEV). This study found that the vectors responsible for transmitting hemoparasitosis, given the high number of serologically positive cases detected in the HVS, represent an increasing risk for TBD. These findings highlight the relevance of companion animal monitoring as an early-warning component within a One Health surveillance approach. Full article

Human granulocytic anaplasmosis is an emerging tick-borne disease. Although Anaplasma phagocytophilum has been identified in vectors and animal reservoirs in Romania, evidence of human exposure has not yet been reported. This study aimed to generate initial evidence of human infection by evaluating A. phagocytophilum antibodies in individuals with recent tick exposure. We conducted a cross-sectional serosurvey between 2023 and 2024 at a tertiary care hospital in Bucharest, enrolling 80 participants 4 to 12 weeks following a tick bite. Serum IgG antibodies against A. phagocytophilum were detected using an indirect immunofluorescence assay, with a titer of ≥1:64 considered indicative of seropositivity. Eight (10%) participants tested positive for A. phagocytophilum IgG antibodies. Seropositivity was not significantly associated with demographics, geographical region, or clinical symptoms. However, fatigue and myalgia were more frequently seen in A. phagocytophilum IgG seropositive individuals. Notably, 43.8% of all participants reported erythema migrans, including five of the eight individuals with positive A. phagocytophilum IgG serology. This study provides the first serological evidence of human exposure to A. phagocytophilum in Romania. A 10% seroprevalence in this high-risk group suggests that anaplasmosis may be underrecognized. Clinicians should consider it in patients with tick exposure and compatible symptoms. Full article

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease predominantly of the small airways and parenchyma. COPD lungs exhibit an influx of circulating innate immune cells, which, when isolated, display impaired functions, including imbalanced protease secretion. In addition to immune cells, the extracellular matrix (ECM) plays a crucial role in COPD pathology. Remodeling of the ECM can generate ECM fragments, which can be released into circulation and subsequently induce pro-inflammatory responses. COPD is a heterogeneous disease, and serological biomarkers can be used to sub-categorize COPD patients for targeted treatments and optimal recruitment in clinical trials. This study evaluated fragments of calprotectin, collagen type VI, and versican, generated by neutrophil elastase and matrix metalloproteinases (MMP-) 2 and 12, respectively, as potential biomarkers of COPD disease, severity, and endotypes. Lower plasma levels of a neoepitope marker of calprotectin, indicative of activated neutrophils (nordicCPa9-HNETM), were detected in COPD donors compared to controls. CPa9-HNE was associated with milder disease, higher degree of air-trapping, and higher serum levels of MMP-2. Deposition of CPa9-HNE levels in lung tissue revealed no differences between groups. Taken together, CPa9-HNE was found to be a potential marker of mild COPD, but further studies are warranted to validate our findings. Full article

Background: Chitosan, a family of polysaccharides composed of glucosamine and N-acetyl glucosamine, is a promising adjuvant candidate for eliciting potent immune response. Methods: This study compared the adjuvant effects of chitosan to those of empty lipid nanoparticles (eLNPs) and aluminum hydroxide (alum) following administration of recombinant SARS-CoV-2 spike immunogen in adult mice. Mice received the adjuvanted recombinant protein vaccine in a prime-boost regimen with four weeks interval. Subsequent analyses included serological assessment of antibody responses, evaluation of T cell activity, immune cell recruitment and cytokine profiles at injection site. Results: Compared to alum, chitosan induced a more balanced Th1/Th2 response, akin to that observed with eLNPs, demonstrating its ability to modulate both the humoral and cellular immune pathways. Chitosan induced a different proinflammatory cytokine (e.g., IL-1⍺, IL-2, IL-6, and IL-7) and chemokine (e.g., Eotaxin, IP-10, MIP-1a) profile compared to eLNPs and alum at the injection site and in the draining lymph nodes. Moreover, chitosan potentiated the recruitment of innate immune cells, with neutrophils accounting for about 40% of the infiltrating cells in the muscle, representing a ~10-fold increase compared to alum and a comparable level to eLNPs. Conclusions: These findings collectively indicate that chitosan has the potential to serve as an effective adjuvant, offering comparable, and potentially superior, properties to those of currently approved adjuvants. Full article

Background: Despite the widespread implementation of childhood vaccination programmes, hepatitis B virus (HBV) infection remains an ongoing occupational risk for healthcare students. In multi-ethnic and international university settings, differences in vaccination programmes and immune responses must be considered. This retrospective study aimed to assess the prevalence of protective levels of anti-HBs among medical students at an international university in Rome, exploring associations with demographic and vaccination-related factors. Methods: Data were collected from routine occupational health surveillance conducted in 2023. Anti-HB titres were measured in 507 students, and information on age, sex, country of birth, age at vaccination, and time since the last dose was analysed. Results: Overall, 55.0% of students had antibody levels of at least 10 mIU/mL, indicating serological protection. Higher seroprotection rates were observed among students vaccinated in the first year of life compared to those vaccinated later. A significant decline in antibody titres was also associated with longer intervals since vaccination. Students born outside Europe tended to show lower levels of protection. Conclusions: These results emphasise the importance of screening future healthcare professionals and continuously monitoring antibody titres to help reduce HBV infections. Full article

Background/Objectives: Histological follow-up still lacks consensus in the long-term management of adult patients with celiac disease (CD) adhering to a gluten-free diet (GFD). Despite clinical and serological improvement, a significant proportion of patients continue to have persistent villous atrophy. We aimed to synthesize current evidence regarding histological outcomes after GFD treatment in adult CD, focusing on mucosal healing rates, assessment methods, and remission criteria. Methods: We conducted a literature search with extraction and analysis of published cohort studies that included adult patients with CD on GFD with follow-up biopsy data. Extracted parameters included demographic details, baseline histology, GFD duration and adherence, serologic status, and histologic recovery rates with corresponding remission criteria. Results: Data from 46 studies comprising 15,530 patients were analyzed. The overall mean age was 41 years, and 73.3% were female. Mean histologic remission across cohorts was 58.8%, with considerable interstudy variation. Remission criteria also varied widely, ranging from strict Marsh 0 control histology to more inclusive definitions that considered Marsh 1 or even non-atrophic mucosa (Marsh < 3) as indicative of recovery, while some studies relied on quantitative villous height-to-crypt depth ratio thresholds, substantially influencing reported remission rates. Longer GFD duration and rigorous diet adherence assessment using validated questionnaires and accurate laboratory tools were associated with higher remission rates. Conclusions: Histologic remission in GFD-treated adult patients with CD is highly variable and strongly influenced by remission definitions and adherence assessment methods. Standardized reporting using validated metrics for histologic outcome and dietary compliance is essential for harmonizing follow-up strategies in adult CD. Full article

Leptospirosis is a (re-)emerging and global zoonotic disease. Given the complex host-pathogen interaction and the numerous environmental risk factors related to the transmission, a One Health approach to both disease prevention and control is needed. Occurring at the human–cattle–environment interfaces, bovine leptospirosis represents a zoonotic risk for the professionals in the field, besides being a potential cause of significant economic losses due to the bovine reproductive disorders. Although climatic change is a potential factor in exacerbating the risk of leptospirosis in Europe, this disease remains largely neglected, with several knowledge gaps in research, investigations, and diagnosis of bovine genital leptospirosis syndrome across the continent. The present report describes the results of the diagnostic investigations on a case of chronic bovine leptospirosis in a breeding bull. Following the seroconversion to Leptospira Sejroe var Hardjo after the arrival of the animal in a quarantine facility, a monitoring plan including both serological/molecular analyses and a therapeutic protocol was undertaken. The bull exhibited a persistent seroconversion and a repeated positivity for Leptospira to real-time PCR in urine samples, indicative of a chronic shedder pattern. This report emphasizes the diagnostic and management challenges in the context of such a complex but frequently overlooked disease. Full article

Young children are particularly vulnerable to measles infections. Investigating the gap between the waning of maternal antibodies and onset of vaccination-induced immunity via seroprevalence studies can be hampered by recruiting enough young-aged participants. We present measles IgG-antibody results from 2148 patients aged 0 to 2 years, who were hospitalized with acute aseptic meningitis or encephalitis in Lower Saxony or Bremen. Measles serology was performed for differential diagnostics clarification of neurotropic pathogens, during syndromic surveillance between 2006 and 2024. At birth, 79% of children presented with measles IgG-antibodies, but only 30% of three-month-old patients and 11% of five-month-olds. From 0 to 10 months, seropositivity declined monthly by 8%. Over 95% of children aged six to 11 months were unprotected. From 11 months onwards, measles seroprevalence increased, reaching 80–90% towards the end of the second year of life. Our results indicate an absence of maternal measles IgG antibodies after nine months of age and that vaccination starts around 11 months of age; however, not all children had received vaccination by their second birthday. These findings confirm the current recommendation to advance first measles vaccination to nine months in high-exposure settings and support efforts to increase vaccination rates in small children and young adults. Full article

Southeast Asia is a biodiversity hotspot for bats that can carry lyssaviruses, causing zoonotic diseases. This study detects and quantifies IgG antibodies against Lyssavirus glycoproteins in cave-dwelling bat populations on Cat Ba Island, northern Vietnam, to determine their past exposure history and the prevalence of immune responses. Samples were collected from five caves, encompassing three families and five key species (Hipposideros armiger, H. alongensis, H. poutensis, Taphozous melanopogon, and Myotis pilosus). Using ELISA with the Platelia™ Rabies II kit,(Bio-Rad Laboratories, Marnes-la-Coquette, France) 29.0% (18/62) of the bats tested positive, indicating prior exposure. The detection rate was slightly higher in females (35.7%) than in males (30.4%). Lyssavirus-specific antibodies were detected in four species, with the highest levels found in M. pilosus, followed by H. alongensis, H. armiger, and H. poutensis; no positives were found in T. melanopogon samples. One bat exhibited high seroconversion value (>4 EU/mL). The findings provide serological evidence of widespread lyssaviruses exposure in asymptomatic bats on Cat Ba Island, confirming their role as reservoirs that elicit an immune response without exhibiting rabies symptoms. This highlights the role of caves in facilitating close contact among bats, which may increase viral transmission, highlighting the need for continued surveillance in these unique roosting environments. Full article

Celiac disease (CD), a human leukocyte antigen-associated disorder, is caused by gluten sensitivity and is characterized by mucosal alterations in the small intestine. Currently, its diagnosis involves the determination of serological markers. The traditional method for clinically determining these markers is the enzyme-linked immunosorbent assay. However, immunosensors offer sensitivity and facilitate the development of miniaturized and portable analytical systems. This work focuses on developing an amperometric immunosensor for the quantification of IgA antibodies against tissue transglutaminase (IgA anti-TGA) in human serum samples, providing information on a critical biomarker for CD diagnosis. The electrochemical device was designed on a polyimide substrate using a novel solid ink of wax and carbon nanofibers (CNFs). The working electrode microzone was defined by incorporating aminofunctionalized TiO₂ nanoparticles (TiO₂NPs). The interactions and morphology of CNFs/wax and TiO₂NPs/CNFs/wax electrodes were assessed through different characterization techniques. Furthermore, the device was electrochemically characterized, demonstrating that the incorporation of CNFs into the wax matrix significantly enhanced its conductivity and increased the active surface area of the electrode, while TiO₂NPs contributed to the immunoreaction area. The developed device exhibited remarkable sensitivity, selectivity, and reproducibility. These results indicate that the fabricated device is a robust and reliable tool for the precise serological diagnosis of CD. Full article

Primary Sjögren’s syndrome (pSS) exhibits considerable clinical and immunological heterogeneity, complicating personalized management. We aimed to delineate the demographic, functional, serological, histopathological, and therapeutic features of a Romanian pSS cohort and to identify biomarker–treatment correlations that could inform patient-oriented strategies. Thirty-two patients meeting the 2016 ACR/EULAR classification criteria for pSS were retrospectively analyzed. Data collected included demographics, autoantibody profiles (Anti-Ro/SSA, Anti-La/SSB, ANA, RF, Anti-CCP), immunoglobulin levels, complement consumption (C3/C4), minor salivary gland biopsy (focus score), salivary flow tests, and systemic inflammation markers (CRP). Pearson correlation matrices were constructed to explore the associations between serological markers and prescribed therapies. The cohort was predominantly female (87.5%) with a mean age of 52.8 ± 9.9 years. Seropositivity rates were 50% for Anti-Ro/SSA, 77% for Anti-La/SSB, and 40% for ANA. Clinically significant glandular dysfunction was evident in 65% of patients (unstimulated flow ≤ 0.1 mL/min), and all biopsies demonstrated focus scores > 1. Methotrexate use correlated strongly with Anti-Ro/SSA and Anti-La/SSB positivity (p ≤ 0.05), indicating its targeted application in seropositive sub-phenotypes. Conclusion: These findings underscore the immunologic and clinical diversity of pSS and support a biomarker-driven, multidisciplinary framework for personalized treatment. Larger prospective and multicenter studies are warranted to validate these correlations and to refine precision medicine approaches in pSS. Full article

Background and Objectives: Pediatric Sjögren’s syndrome is a rare autoimmune disease with a heterogeneous clinical expression and limited pediatric-specific diagnostic criteria. Ocular involvement often represents an early manifestation, yet it may go unrecognized in children due to poor symptom reporting and the underuse of objective diagnostic tools. This retrospective study evaluated six pediatric patients with Sjögren’s syndrome, integrating systemic and ocular findings with a focus on early immunological and clinical markers. Materials and Methods: All patients underwent ophthalmological assessments, including tear break-up time, Schirmer’s test, and slit-lamp examination. Results: Tear break-up time values consistently indicated tear film instability (mean RE 7.4 ± 2.5 s; LE 7.7 ± 2.3 s), while Schirmer’s test showed greater variability. Slit-lamp examination revealed inhomogeneous tear films in all patients and blepharitis in 66.7%, consistent with Meibomian gland dysfunction. Systemic features included arthralgia, Raynaud’s phenomenon, fatigue, and frequent seropositivity for ANA and anti-SSA/Ro antibodies. Minor salivary gland biopsy confirmed lymphoepithelial sialadenitis in all cases. Conclusions: These findings highlight the importance of combining laboratory and clinical markers with ophthalmological parameters to support an early diagnosis of Sjögren’s syndrome in pediatric patients. Integrating TBUT and slit-lamp evaluation with serological and histopathological data may enhance diagnostic accuracy and guide timely, targeted intervention to prevent long-term complications. Full article

Infectious bursal disease virus (IBDV) is one of the most important immunosuppressive viruses in poultry, causing the global spread of infectious bursal disease (IBD). It poses a significant threat to the healthy development of the poultry industry. Vaccination is an effective approach for controlling IBDV infection. Therefore, reliable immune monitoring for IBDV is critical for maintaining poultry health. The enzyme-linked immunosorbent assay (ELISA) is a common technique used to detect specific antibodies in clinical serum testing and for the serological evaluation of IBDV vaccines. Among the currently available and under development IBDV vaccines, IBD VP2 subunit-based vaccines account for a considerable proportion. These vaccines stimulate the production of antibodies that are specific only to VP2. However, most IBDV antibody ELISA kits approved for use have applied the whole virus as the coating antigen, which does not adequately meet the diverse requirements for IBDV detection across different conditions. This study utilized a prokaryotic expression system to express the VP2 protein of the IBDV epidemic strain, assembling it into virus-like particles to be used as coating antigens. This approach enabled the establishment of an indirect ELISA method for detecting IBDV VP2 antibody (VP2-ELISA). The optimal coated antigen concentration was determined to be 2.5 μg/mL, with overnight coating at 4 °C; sealing with 5% skim milk at 37 °C for 4 h; serum dilution at 1:500 with incubation at 37 °C for 30 min; secondary antibody dilution at 1:4000 with incubation at 37 °C for 40 min; and then incubation with the substrate solution 3,3′,5,5′-tetramethylbenzidine at room temperature for 20 min. The criterion for interpreting the detection results was OD_450nm ≥ 0.111 indicates IBDV antibody positivity, while OD_450nm < 0.111 indicates negativity. The established VP2-ELISA can specifically detect IBDV-positive sera at the lowest serum dilution of 1:6400, with intra- and inter-batch coefficients of variation of <2%. This indicates that the VP2-ELISA exhibits good specificity, sensitivity, and stability. Detection experiments using 20 laboratory-immunized chicken serum samples and 273 clinical serum samples demonstrated that the results of VP2-ELISA were consistent with those of commercial ELISA kits coated with whole virus. In summary, the VP2-ELISA developed in this study offers advantages in immune response detection for IBD VP2 subunit-based vaccines and is appropriate for evaluating the efficacy of IBD vaccines and detecting clinical serum samples. Full article

The wild boar (Sus scrofa) has experienced significant population growth as well as geographic expansion across Europe over the past 15 years, leading to increased concerns regarding its role in the transmission of zoonotic pathogens. Among these, Babesia spp. and Anaplasma spp. are of particular importance due to their impact on both wildlife and domestic animals. This study systematically reviews the prevalence and distribution of Babesia and Anaplasma spp. in wild boars and associated tick vectors across multiple European countries, synthesizing data from literature published between 2010 and 2024. A comprehensive search of Scopus, Google Scholar, and PubMed databases was conducted using predefined keywords related to babesiosis, anaplasmosis, wild boars, Europe, and tick-borne diseases. A total of 281 studies were initially retrieved, of which 19 met the inclusion criteria following relevance assessment. Data extraction focused on pathogen identification, diagnostic methods, sample type, host species, and prevalence rates. Molecular detection methods, primarily PCR and sequencing, were the most used diagnostic tools. Results indicate substantial regional variations in the prevalence of Babesia and Anaplasma spp. A. phagocytophilum was detected in wild boar populations across multiple countries, with the highest prevalence rates observed in Slovakia (28.2%) and Poland (20.34%). Conversely, lower prevalence rates were recorded in France (2%) and Portugal (3.1%). Babesia spp. showed higher prevalence rates in Italy (6.2%), while its detection in other regions such as Romania and Spain was minimal or absent. Notably, spleen and multi-organ samples (spleen/liver/kidney) exhibited higher positivity rates compared to blood samples, suggesting an organotropic localization of these pathogens. The findings underscore the role of wild boars as reservoirs for tick-borne pathogens and highlight their potential to contribute to the epidemiological cycle of these infections. The increasing distribution of wild boars, coupled with climate-driven shifts in tick populations, may further facilitate pathogen transmission. Future studies should focus on integrating molecular, serological, and ecological approaches to improve surveillance and risk assessment. Standardized methodologies across different regions will be essential in enhancing comparative epidemiological insights and informing targeted disease management strategies. Full article