Search Results (562)

Varicocele is a common, potentially correctable condition associated with impaired male fertility. Despite being frequently encountered in clinical andrology, its pathophysiological mechanisms, diagnostic criteria, and therapeutic approaches remain areas of active investigation and debate. The authors conducted a comprehensive literature search, using the PubMed database, covering clinical studies, systematic reviews, meta-analyses, and current international guidelines from the past ten years. Emphasis was placed on studies investigating novel diagnostic modalities, therapeutic innovations, and prognostic markers. Emerging evidence supports the multifactorial pathophysiology of varicocele, involving oxidative stress, hypoxia, inflammatory pathways, and potential genetic predisposition. Biomarkers, including microRNAs, antisperm antibodies, and sperm DNA fragmentation, offer diagnostic and prognostic utility, though their routine clinical implementation requires further validation. Advances in imaging, such as shear wave elastography, may improve diagnostic accuracy. While microsurgical subinguinal varicocelectomy remains the gold standard, technological refinements and non-surgical alternatives are being explored. Indications for treatment have expanded to include selected cases of non-obstructive azoospermia, hypogonadism, and optimization for assisted reproduction, though high-level evidence is limited. Full article

Background/Objectives: High-risk neuroblastoma patients are treated with approved anti-ganglioside GD2 antibodies of moderate (dinutuximab beta; DB) and higher binding affinity (naxitamab; NAXI). We evaluated the functional potency of DB compared to NAXI and investigated the target-mediated drug disposition (TMDD). Methods: Tumor spheroids were generated from neuroblastoma cells with varying GD2 expression, stably expressing iRFP680 as a viability marker. Antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) were assessed in a long-term life-cell viability assay using serial dilutions of the GD2 antibodies. Binding activity was determined by flow cytometry. Processes involved in TMDD were analyzed, including antibody binding to dead tumor cells and to soluble GD2 (sGD2), antibody internalization into tumor and immune cells and the impact of sGD2 on DB and NAXI-mediated ADCC. Results: DB and NAXI mediated a concentration-dependent ADCC response against GD2-positive spheroids and no response against GD2-negative spheroids. DB showed a significantly higher ADCC potency than NAXI in all GD2-positive spheroid models. Binding activity of DB and NAXI was not significantly different. However, the decrease of anti-GD2 antibody binding to viable GD2-positive tumor cells following co-incubation with dead GD2-positive tumor cells or sGD2 was significantly higher for NAXI than DB. Additionally, we found an increased internalization of NAXI compared to DB by tumor cells and particularly CD64+ monocytes. Finally, sGD2 impaired NAXI-mediated ADCC to a significantly greater extent than DB-mediated ADCC. Conclusions: DB has a higher ADCC potency over NAXI at clinically relevant concentrations, attributed to stronger TMDD effects of NAXI compared to DB. Full article

Porcine Rotavirus (PoRV), a predominant causative agent of neonatal diarrhea in piglets, shares substantial genetic homology with human rotavirus and represents a considerable threat to both public health and the global swine industry in the absence of specific antiviral interventions. The VP6 protein, an internal capsid component, is characterized by exceptional sequence conservation and robust immunogenicity, rendering it an ideal candidate for viral genotyping and vaccine development. In the present study, the recombinant plasmid pET28a(+)-VP6 was engineered to facilitate the high-yield expression and purification of the VP6 antigen. BALB/c mice were immunized to generate monoclonal antibodies (mAbs) through hybridoma technology, and the antigenic specificity of the resulting mAbs was stringently validated. Subsequently, a panel of truncated protein constructs was designed to precisely map linear B-cell epitopes, followed by comparative conservation analysis across diverse PoRV strains. Functional validation demonstrated that all three mAbs exhibited high-affinity binding to VP6, with a peak detection titer of 1:3,000,000 and exclusive specificity toward PoRVA. These antibodies effectively recognized representative genotypes such as G3 and X1, while exhibiting no cross-reactivity with unrelated viral pathogens; however, their reactivity against other PoRV serogroups (e.g., types B and C) remains to be further elucidated. Epitope mapping identified two novel linear B-cell epitopes, ¹²⁸YIKNWNLQNR¹³⁷ and ¹³⁸RQRTGFVFHK¹⁴⁷, both displaying strong sequence conservation among circulating PoRV strains. Collectively, these findings provide a rigorous experimental framework for the functional dissection of VP6 and reinforce its potential as a valuable diagnostic and immunoprophylactic target in PoRV control strategies. Full article

Background and Objectives: Cardiac transplantation is currently the elective treatment choice in end-stage heart failure, and cellular rejection is a predictive factor for morbidity and mortality after surgery. We proposed an evaluation of the clinicopathologic factors involved in the mechanism of rejection. Materials and Methods: This study included 146 patients who underwent transplantation at the Institute of Cardiovascular Diseases and Transplantation in Targu Mures between 2010 and 2023, and we evaluated the function and structure of the myocardium after surgery by using endomyocardial biopsy. Results: Overall, 120 men and 26 women underwent transplantation, with an approximately equal proportion under and over 40 years old (48.6% and 51.4%). Evaluating the degree of acute cellular rejection according to the International Society for Heart and Lung Transplantation classification showed that most of the patients presented with acute cellular rejection (ACR) and antibody-mediated rejection (AMR) grade 0, and most cases of ACR and AMR were reported with mild changes (13% or 10.3% patients). Therefore, the most frequent histopathologic diagnoses were similar to lesions unrelated to rejection (45.2% of patients) and ischemia–reperfusion lesions (25.3% patients), respectively. Conclusions: Although 82.2% of the transplanted cases showed no rejection (ISHLT score 0), non-rejection-related lesion-like changes were present in 45.2% of cases, and because more of the non-rejection-related criteria could be detected, it may be necessary to adjust the grading of the rejection criteria. The histopathologic changes that characterize rejection are primarily represented by the mononuclear inflammatory infiltrate; in our study, inflammatory changes were mostly mild (71.9%), with myocyte involvement in all cases. These changes are associated with and contribute to the maintenance of the rejection phenomenon. Full article

Background/Objectives: Anti-drug antibody (ADA) formation can impact the safety, pharmacokinetics, and/or efficacy of biotherapeutics, including monoclonal antibodies (mAbs). Current strategies for ADA/immunogenicity risk prediction of mAbs include in silico algorithms, T cell proliferation assays, MHC-associated peptide proteomics assays (MAPPs), and dendritic cell internalization assays. However, B cell-mediated responses are not assessed in these assays. B cells are professional antigen-presenting cells (APCs) and secrete antibodies toward immunogenic mAbs. Therefore, methods to determine B cell responses would be beneficial for immunogenicity risk prediction and may provide a more comprehensive assessment of risk. Methods: We used a PBMC culture method with the addition of IL-4, IL-21, B cell activating factor (BAFF), and an anti-CD40 agonist mAb to support B cell survival and activation. Results: B cells in this assay format become activated, proliferate, and secrete IgG. A panel of 51 antibodies with varying clinical immunogenicity rates were screened in this assay with IgG secretion used as a readout for immunogenicity risk. IgG secretion differed among test articles but did not correlate with the clinical immunogenicity rating. Conclusions: This dataset highlights the challenges of developing a B cell assay for immunogenicity risk prediction and provides a framework for further refinement of a B cell-based assay for immunogenicity risk prediction of mAbs. 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

The rapid development of therapies using oncolytic viruses (OVs) has highlighted their unique advantages, such as their selective replication in tumor cells and their activation of a specific systemic antitumor immune response. However, effectively delivering OVs to tumor sites, especially solid tumor sites, remains a critical challenge. Intratumoral injections face significant barriers in treating some malignant tumors in internal organs, while increasing preclinical data support the use of intravenous injections. Nevertheless, intravenously injected viral particles may be prematurely cleared by circulating antibodies or complements, resulting in a reduced virus dose effectively reaching the tumor site. Therefore, developing methods to shield viruses from the neutralizing environment of the bloodstream while heading toward tumor sites is a must. In this review, we discuss some of the most promising delivery methods for OVs currently under investigation. Full article

Background: Inflammatory breast cancer (IBC) is a rare and aggressive subtype of breast cancer that accounts for 1–5% of BC patients and regularly affects women under 40 years of age. Approximately 50% of IBC cases are HER2+ and can be treated with the monoclonal antibody-based therapy Herceptin (trastuzumab). However, resistance to Herceptin develops within a year, and effective second-line targeted therapies are currently unavailable for IBC patients. Lipocalin-2 (LCN2) is a promising therapeutic target for IBC due to its role in promoting tumor invasiveness, angiogenesis, and the inflammatory tumor microenvironment characteristic of IBC. Objective: We developed Herceptin-conjugated liposomes loaded with LCN2-targeted small-interference RNA (siRNA) for HER2+ IBCs. Methods: We synthesized DSPE-PEG(2000)-maleimide-Herceptin in a three-step process and formulated the liposomes together with DOPC, PEG(2000)-PE, cholesterol, and siRNA. Results: Dynamic light scattering confirmed the liposome size distribution, which was 66.7 nm for the Herceptin-conjugated liposome versus 43.0 nm in a non-functionalized liposome. Here, we report efficient internalization of this formulation into HER2+ IBC cells, reducing LCN2 levels by 30% and disrupting tumor emboli formation. RNA sequencing revealed 139 genes that were differentially expressed upon LCN2 knockdown, with 25 canonical pathways identified through Ingenuity Pathway Analysis. Conclusions: These findings suggest that LCN2-targeted siRNA within Herceptin-targeted liposomes represents a promising therapeutic strategy for IBC. Full article

Malaria is still one of the biggest global health problems, especially in parts of the world, such as sub-Saharan Africa, which remains most heavily affected. Despite significant advancements in testing, treatment, and prevention, malaria continues to seriously impact millions, primarily young children and populations in rural and impoverished areas. This paper looks at how the malaria parasite works inside the body, how it avoids the immune system, and how it becomes resistant to current drugs. Thanks to new advances in genetic and biochemical research, scientists are discovering new weak points in the parasite that could lead to better treatments. New vaccines, like RTS, S and R21, along with antibody-based therapies, offer renewed hope; however, extending the duration of the immunity they induce and ensuring effectiveness across diverse parasite strains remain significant challenges. Solving the malaria crisis will require more than science—it also necessitates equitable and timely access to treatments, robust health systems, and international collaboration. Continued research and global cooperation bring the world closer to ending malaria for good. Full article

Background: An effective vaccine against Nipah virus (NiV) is crucial due to its high fatality rate and recurrent outbreaks in South and Southeast Asia. Vaccine development is challenged by the lack of validated accessible neutralization assays, as virus culture requires BSL-4 facilities, restricting implementation in resource-limited settings. To address this, we standardized and validated a pseudotyped virus neutralization assay (PNA) for assessing NiV-neutralizing antibodies in BSL-2 laboratories. Methods: The NiV-PNA was validated following international regulatory standards, using a replication-defective recombinant Vesicular stomatitis virus (rVSV) backbone dependent pseudotyped virus. Assessments included sensitivity, specificity, dilutional linearity, relative accuracy, precision, and robustness. The assay was calibrated using the WHO International Standard for anti-NiV antibodies and characterized reference sera to ensure reliable performance. Findings: Preliminary evaluation of the developed NiV-PNA showed 100% sensitivity and specificity across 10 serum samples (5 positive, 5 negative), with a positive correlation to a calibrated reference assay (R² = 0.8461). Dilutional linearity (R² = 0.9940) and accuracy (98.18%) were confirmed across the analytical titer range of 11-1728 IU/mL. The assay also exhibited high precision, with intra-assay and intermediate precision geometric coefficients of variation of 6.66% and 15.63%, respectively. Robustness testing demonstrated minimal variation across different pseudotyped virus lots, incubation times, and cell counts. Conclusions: The validated NiV-PNA is a reproducible and scalable assay platform for quantifying NiV neutralizing antibodies, offering a safer alternative to virus culture. Its validation and integration into the CEPI Centralized Laboratory Network will enhance global capacity for vaccine evaluation and outbreak preparedness. Full article

Brucellosis continues to be a significant global zoonotic infection, with diagnosis largely relying on the detection of antibodies against the Brucella O-polysaccharide (O-PS) A and M antigens. In this study, computational methods, including homology modeling, molecular docking, and molecular dynamics simulations, were applied to investigate the interaction of the four murine monoclonal antibodies (mAbs) YsT9.1, YsT9.2, Bm10, and Bm28 with hexasaccharide fragments of the A and M epitopes. Through stringent stability criteria, based on interaction energies and mobility of the antigens, high-affinity binding of A antigen with YsT9.1 antibody and M antigen with Bm10 antibody was predicted. In both the complexes hydrophobic interactions dominate the antigen–antibody binding. These findings align well with experimental epitope mapping, indicating YsT9.1’s preference for internal sequences of the A epitope and Bm10’s preference for internal elements of the M epitope. Interestingly, no stable complexes were identified for YsT9.2 or Bm28 interacting with A or M antigen. This study provides valuable insights into the mechanism of molecular recognition of Brucella O-antigens that can be applied for the development of improved diagnostics, synthetic glycomimetics, and improved vaccine strategies. Full article

Assessment for the presence or absence of lupus anticoagulant (LA) represents a common investigation in hemostasis laboratories. In particular, LA represents one of the laboratory criteria for the diagnosis of definite antiphospholipid syndrome (APS). The other laboratory criteria are the solid phase assays (anticardiolipin (aCL) and anti-β2Glycoprotein I (aβ2GPI) antibodies of IgG and IgM isotypes). Current International Society on Thrombosis and Haemostasis (ISTH) guidance recommends testing LA by at least two tests based on different principles, with the activated partial thromboplastin time (aPTT) and dilute Russell viper venom time (dRVVT) being preferred. Additional assays may be used in addition, or instead of these assays in particular situations. For example, aPTT and dRVVT assays are very sensitive to the presence of various anticoagulants, and this may lead to false-positive identification of LA. This is particularly problematic in the age of the DOACs (direct oral anticoagulants), which are now the leading anticoagulants in use worldwide. We review recent literature on LA testing as well as our local practice to provide an update on this common test procedure. Our experience should be useful for laboratories struggling with LA interpretation for diagnosis or exclusion of APS. Full article

Background. To meet the WHO’s viral hepatitis elimination goal by 2030, the Minister of Health (Italy) introduced free HCV screening among people born between 1969 and 1989 and those at greater risk (people in the care of the addiction services and detained). Aims. To estimate the following: (i) the prevalence of HCV in hospitalized patients born before 1969 not included in the free HCV screening, (ii) the prevalence of transaminase values outside the range, and (iii) the HBV prevalence in a subgroup of patients. Methods. Anti-HCV antibodies and transaminase values were prospectively evaluated in patients born before 1969 and admitted to the Santa Maria alle Scotte Hospital in Siena. The first screening (October 2021–July 2022) was conducted in the Internal Medicine Division (cohort 0), and the second one (May 2024–October 2024) in Internal Medicine, Gastroenterology, and Geriatric Units (cohorts 1–3), including clinical features and HBV markers in a subgroup of patients. Results. Overall, 774 subjects underwent HCV screening. In the first screening period, 1.4% (8/567) of patients were anti-HCV+, of whom 0.7% were HCV RNA+ (4/567). In the second, 3.9% of patients (8/207) were anti-HCV+ and 0.9% were viremic (2/207). Overall, HCV prevalence was 0.8%. Of 96 patients in the gastroenterology cohort, 8 patients were at risk for occult HBV infection (8.3%). Conclusions. Our study demonstrates a chronic HCV infection prevalence of 0.8% in hospitalised patients born before 1969 and a prevalence of 8.3% of people at risk for occult HBV infection in a subgroup of patients residing in South-Eastern Tuscany, confirming that an opportunistic screening can identify the unrecognized people affected by viral hepatitis. Full article

The resistance of breast cancer cells to therapeutic antibodies such as anti-HER2 trastuzumab can be overcome by engaging natural killer (NK) cells for killing antibody-binding tumor cells via antibody-dependent cellular cytotoxicity (ADCC). Here, we investigated how autophagy modulation affects trastuzumab-mediated ADCC in HER2-positive JIMT1 breast cancer cells and NK cells. Autophagy inducers (rapamycin and resveratrol) had no significant impact, but the inhibitor bafilomycin nearly abolished ADCC. Protection occurred when either cancer or NK cells were pretreated, indicating dual effects. Bafilomycin reduced phosphatidylserine externalization, the loss of plasma membrane integrity, caspase-3/7 activity, and DNA fragmentation. It downregulated pro-apoptotic BAK1 and BAX without altering BCL-2. Additionally, bafilomycin decreased HER2 surface expression, impairing trastuzumab binding, and modulated immune regulators (STAT1, CD95, and PD-L1) in NK and/or in the cancer cells. Bafilomycin disrupted HER2 trafficking and induced HER2 internalization, leading to its accumulation in cytoplasmic vesicles. These findings show that autophagy inhibition by bafilomycin confers ADCC resistance by altering apoptosis, immune signaling, and HER2 dynamics. The study underscores autophagy’s role in antibody-based cancer therapy efficacy. Full article

Droplet microfluidics has emerged as a transformative technology that can substantially increase the throughput of antibody “hit” discovery. This review provides a comprehensive overview of the recent advances in this dynamic field, focusing primarily on the technological and methodological innovations that have enhanced the antibody discovery process. This investigation starts with the fundamental principles of droplet microfluidics, emphasizing its unique capabilities for precisely controlling and manipulating picoliter-volume droplets. This discussion extends to various assay types employed in droplet microfluidics, including binding assays, functional assays, Förster Resonance Energy Transfer (FRET) assays, internalization assays, and neutralization assays, each offering distinct advantages for antibody screening and characterization. A critical examination of methods to improve droplet encapsulation is presented, besides addressing challenges such as reducing the leakage of small molecules from droplets and explaining what a “hit” droplet looks like. Furthermore, we assess design considerations essential for implementing high-throughput fluorescence-activated droplet sorting (FADS) workstations and emphasize the need for automation. This review also delves into the evolving commercial landscape, identifying key market players and emerging industry trends. This review paper aims to catalyze further research and innovation, ultimately advancing the field towards more efficient and robust solutions for antibody identification and development. Full article