Search Results (550)

Viral outbreaks have caused significant mortality and economic losses in aquaculture, highlighting the urgent need for effective therapies and a deeper understanding of antiviral and immune mechanisms in key species. This study investigates the constitutive and virus-induced antiviral responses in juvenile rainbow trout (Oncorhynchus mykiss) following infection with viral hemorrhagic septicemia virus (VHSV). Trout (30 g) were infected by immersion with VHSV (TCID₅₀ = 10⁵ mL⁻¹) for two hours. Samples were collected at 24, 72, and 120 h post-infection to assess hematology, innate immunity, viral load, and transcriptomic response. At 24 h post-infection, no immune response or increase in viral load was detected, suggesting the host had not yet recognized the virus and was still in the incubation phase. By 72 h, viral replication peaked, with high viral loads observed in mucosal tissues (skin and gills) and immune organs (kidney, spleen, liver), alongside strong up-regulation of antiviral genes, such as viperin. This gene maintained high expression through the final sampling point, indicating its key role in the antiviral response. At this stage, reduced immune competence was observed, marked by elevated nitric oxide and circulating thrombocytes. At 120 h, modest increases in peripheral monocyte, plasma lysozyme, and peroxidase activity were detected; however, these responses were insufficient to reduce viral load, suggesting the resolution phase had not yet begun. In summary, while a limited immune response was observed by the end of the trial, the consistent antiviral activity of viperin from peak infection to 120 h post-infection underscores its importance in the defence against VHSV in rainbow trout. Full article

Nipah virus (NiV) is a highly pathogenic bat-borne zoonotic pathogen that poses a significant threat to human and animal health, with fatality rates exceeding 70% in some outbreaks. Despite its significant public health impact, there are currently no licensed vaccines or specific therapeutics available. Various virological tools—such as reverse genetics systems, replicon particles, VSV-based pseudoviruses, and recombinant Cedar virus chimeras—have been widely used to study the molecular mechanisms of NiV and to support vaccine development. Building upon these platforms, we developed a replication-competent recombinant vesicular stomatitis virus (rVSVΔG-eGFP-NiV_BD F/G) expressing NiV attachment (G) and fusion (F) glycoproteins. This recombinant virus serves as a valuable tool for investigating NiV entry mechanisms, cellular tropism, and immunogenicity. The virus was generated by replacing the VSV G protein with NiV F/G through reverse genetics, and protein incorporation was confirmed via immunofluorescence and electron microscopy. In vitro, the virus exhibited robust replication, characteristic cell tropism, and high viral titers in multiple cell lines. Neutralization assays showed that monoclonal antibodies HENV-26 and HENV-32 effectively neutralized the recombinant virus. Furthermore, immunization of golden hamsters with inactivated rVSVΔG-eGFP-NiV_BD F/G induced potent neutralizing antibody responses, demonstrating its robust immunogenicity. These findings highlight rVSVΔG-eGFP-NiV_BD F/G as an effective platform for NiV research and vaccine development. Full article

Background: Boiling histotripsy (BH) uses high-amplitude, short-pulse focused ultrasound to disrupt tissue mechanically. Oncolytic virotherapy using reovirus has shown modest clinical benefit in pancreatic cancer patients. Here, reovirus and BH were used to treat pancreatic tumours, and their effects on the immune transcriptome of these tumours were characterised. Methods: Orthotopic syngeneic murine pancreatic KPC tumours grown in immune-competent subjects, were allocated to control, reovirus, BH and combined BH and reovirus treatment groups. Acoustic cavitation was monitored using a passive broadband cavitation sensor. Treatment effects were assessed histologically with hematoxylin and eosin staining. Single-cell multi-omics combining whole-transcriptome analysis with the expression of surface-expressed immune proteins was used to assess the effects of treatments on tumoural leukocytes. Results: Acoustic cavitation was detected in all subjects exposed to BH, causing cellular disruption in tumours 6 h after treatment. Distinct cell clusters were identified in the pancreatic tumours 24 h post-treatment. These included neutrophils and cytotoxic T cells overexpressing genes associated with an N2-like and an exhaustion phenotype, respectively. Reovirus decreased macrophages, and BH decreased regulatory T cells compared to controls. The combined treatments increased neutrophils and the ratio of various immune cells to Treg. All treatments overexpressed genes associated with an innate immune response, while ultrasound treatments downregulated genes associated with the transporter associated with antigen processing (TAP) complex. Conclusions: Our results show that the combined BH and reovirus treatments maximise the overexpression of genes associated with the innate immune response compared to that seen with each individual treatment, and illustrate the anti-immune phenotype of key immune cells in the pancreatic tumour microenvironment. Full article

Herpesviruses are DNA viruses that evade the immune response and persist as lifelong infections. Human gamma-herpesviruses Epstein–Barr virus (EBV) and Kaposi’s sarcoma herpesvirus (KSHV) are oncogenic; they can lead to cancer. Oncogenic viruses are responsible for 10–15% of human cancer development, which can have poor prognoses. Non-coding RNAs (ncRNAs) are RNAs that regulate gene expression without encoding proteins, and are being studied for their roles in viral immune evasion, infection, and oncogenesis. ncRNAs are classified by their size, and include long non-coding RNAs, microRNAs, and circular RNAs. EBV and KSHV manipulate host ncRNAs, and encode their own ncRNAs, regulating host processes and immune responses. Viral ncRNAs regulate host functions by post-transcriptionally modifying host RNAs, and by serving as mimics of other host RNAs, promoting immune evasion. ncRNAs in gamma-herpesvirus infection are also important for tumorigenesis, as dampening immune responses via ncRNAs can upregulate pro-tumorigenic pathways. Emerging topics such as RNA modifications, target-directed miRNA degradation, competing endogenous RNA networks, and lncRNA/circRNA–miRNA interactions provide new insights into ncRNA functions. This review compares ncRNAs and the mechanisms of viral immune evasion in EBV and KSHV, while also expanding on recent developments in the roles of ncRNAs in immune evasion, viral infection, and oncogenesis. Full article

Torquetenovirus (TTV) is a ubiquitous, non-pathogenic DNA virus that has been suggested as a biomarker of immune competence, with the viral load correlating with the level of immunosuppression. However, by detecting non-intact viral particles, standard PCR-based quantification may overestimate the TTV viremia. To improve the clinical relevance of TTV quantification, in this study, we investigated the use of PMAxx™, a virion viability dye that selectively blocks the amplification of compromised virions. Serum samples from 10 Hepatitis C Virus-positive (HCV+) individuals, 81 liver transplant recipients (LTRs), and 40 people with HIV (PWH) were treated with PMAxx™ and analyzed for TTV DNA loads by digital droplet PCR (ddPCR). Furthermore, anti-SARS-CoV-2 IgG levels and neutralizing antibody (nAbs) titers were measured post-COVID-19 vaccination. Using ddPCR, the PMAxx™ treatment significantly reduced the TTV DNA levels in all the groups (mean reduction: 0.66 Log copies/mL), indicating the abundant presence of non-intact, circulating viral genomes. However, correlations between TTV DNA and SARS-CoV-2 IgG or nAbs were weak or absent in both PMAxx™-treated and untreated samples. These findings suggest that while PMAxx™ enhanced the specificity of TTV quantification, it did not improve the predictive value of TTV viremia at assessing vaccine-induced humoral responses. Full article

The success of checkpoint inhibitors in improving cancer patient survival has demonstrated the therapeutic potential of immunotherapies. This advancement has reshaped oncology treatment and driven interest in harnessing immune modulation for a wider range of diseases. However, developing drugs that modulate immune activity presents unique challenges. A major limitation in preclinical research is the inefficiency of testing human-specific immune targets in animal models, which often fail to translate to clinical outcomes. Additionally, conventional in vitro systems lack immune reactivity due to their static and monocellular nature, limiting their predictive value. Advanced in vitro models can bridge this gap by offering increasingly relevant human physiology for testing drug efficacy and safety, along with absorption, distribution, metabolism, and excretion (ADME). In particular, immune-competent spheroids, organoids, and organs-on-a-chip (OoC) have emerged as promising tools. Although still in their infancy, these microphysiological systems (MPSs) have demonstrated the feasibility of replicating immune responses ex vivo, providing a new avenue for studying immune-targeting drugs with higher translational potential. In this review, we explore recent advances in immune-competent organoid and OoC models, highlighting their capabilities and limitations. We provide a perspective on their applications for cancer drug testing, discussing how these systems could refine preclinical immuno-oncology research and accelerate the development of next-generation immunotherapies. Full article

Pediatric high-grade gliomas (pHGGs), particularly diffuse midline gliomas (DMGs), are among the most lethal brain tumors due to poor survival and resistance to therapies. DMGs possess a distinct genetic profile, primarily driven by hallmark mutations such as H3K27M, ACVR1, and PDGFRA mutations/amplifications and TP53 inactivation, all of which contribute to tumor biology and therapeutic resistance. Developing physiologically relevant preclinical models that replicate both tumor biology and the tumor microenvironment (TME) is critical for advancing effective treatments. This review highlights recent progress in in vitro, ex vivo, and in vivo models, including patient-derived brain organoids, genetically engineered mouse models (GEMMs), and region-specific midline organoids incorporating SHH, BMP, and FGF2/8/19 signaling to model pontine gliomas. Key genetic alterations can now be introduced using lipofectamine-mediated transfection, PiggyBac plasmid systems, and CRISPR-Cas9, allowing the precise study of tumor initiation, progression, and therapy resistance. These models enable the investigation of TME interactions, including immune responses, neuronal infiltration, and therapeutic vulnerabilities. Future advancements involve developing immune-competent organoids, integrating vascularized networks, and applying multi-omics platforms like single-cell RNA sequencing and spatial transcriptomics to dissect tumor heterogeneity and lineage-specific vulnerabilities. These innovative approaches aim to enhance drug screening, identify new therapeutic targets, and accelerate personalized treatments for pediatric gliomas. Full article

Background/objectives: Nutritional status is increasingly acknowledged as a pivotal determinant of clinical course and recovery in patients with acute ischemic stroke (AIS). Malnutrition can compromise immune competence, delay neurological recovery, and exacerbate adverse outcomes, particularly in those undergoing intensive interventions such as mechanical thrombectomy (MT). To objectively assess nutritional status, indices such as the Prognostic Nutritional Index (PNI) and the Controlling Nutritional Status (CONUT) score have been utilized in various clinical populations. These indices incorporate routinely available laboratory parameters, reflecting both nutritional and inflammatory states. This study explores whether PNI and CONUT scores are associated with 90-day clinical outcomes in AIS patients treated with MT, aiming to evaluate their potential utility as prognostic biomarkers in acute stroke care. Methods: A total of 404 patients with AIS who underwent MT between 2023 and 2024 were retrospectively evaluated. Demographic, clinical, and laboratory data were collected, and nutritional status was assessed using PNI and CONUT scores. Clinical outcomes were stratified as favorable (modified Rankin Scale [mRS] 0–2) or unfavorable (mRS 3–6) at 90 days post-stroke. Results: Among the 404 patients included in the study, 50.5% had favorable and 49.5% had unfavorable clinical outcomes. Patients with favorable outcomes were younger (71 vs. 78 years, p = 0.001), had lower National Institutes of Health Stroke Scale (NIHSS) scores, and higher Alberta Stroke Program Early CT Scores (ASPECTS) (p = 0.001). The puncture-to-recanalization time was significantly longer in the unfavorable outcome group (47.5 min vs. 30.0 min, p = 0.003). Laboratory findings revealed higher glucose levels (p = 0.029), and lower serum albumin (p = 0.003) and lymphocyte levels (p = 0.001) in the unfavorable outcome group. Among nutritional indices, the CONUT score was significantly higher in the unfavorable outcome group (p = 0.001), whereas the PNI score was higher in the favorable outcome group (p = 0.001). ROC analysis showed that the CONUT score had significant prognostic performance (AUC = 0.721, p < 0.001), while the PNI had poor discriminatory power (AUC = 0.274, p < 0.001). Multivariate logistic regression identified age, baseline NIHSS, ASPECT score, and CONUT score as independent predictors of clinical outcome (p < 0.05). Conclusions: Among the two nutritional indices evaluated, the CONUT score demonstrated significant prognostic value in predicting 90-day clinical outcomes after MT. In contrast, the PNI showed limited discriminatory power, highlighting the superiority of CONUT as a reliable biomarker in acute stroke care. Full article

Programmed Death-Ligand 1 (PD-L1) is a major target for immunotherapy using checkpoint inhibitors (CPIs), particularly in lung cancer treatment. Tumoral PD-L1 expression has been recognized as a natural predictor of CPI response. This predictive relationship is primarily due to its upregulation by interferon-gamma, which is released by immune cells (mainly T lymphocytes and natural killer cells) in proximity to tumor cells, driving an immune resistance mechanism. However, PD-L1 expression is modulated at multiple levels, including oncogenic signaling pathways, and transcriptional and post-transcriptional regulations, potentially leading to false positive predictions. Conversely, variable glycosylation of PD-L1 may compromise the accuracy of immunohistochemical measurements, resulting in false negative predictive data. In addition, PD-L1 expression demonstrates relative instability throughout treatment courses (e.g., chemotherapy and tyrosine kinase inhibitors), further limiting its clinical utility. In this review, we focused on the molecular mechanisms governing PD-L1 expression with a special emphasis on lung cancer. We also discussed biomarker strategies for optimizing patient selection for checkpoint inhibitor therapy where multimodal/multi-omics meta-biomarker approaches are emerging. Such comprehensive PD-L1-enriched biomarker strategies require evaluation through large-scale prospective studies, particularly in lung cancer, where numerous competing predictive candidates exist for CPI response. Full article

Cell therapy is promising for heart failure treatment, with growing interest in cardiovascular progenitor cells (CPCs) from pluripotent stem cells. A major challenge is managing the immune response, due to their allogeneic source. Regulatory T cells (Treg) offer an alternative to pharmacological immunosuppression by inducing immune tolerance. This study assesses whether Treg therapy can mitigate the xeno-immune response, improving cardiac outcomes in a mouse model of human CPC intramyocardial transplantation. CPCs stimulated immune responses in allogeneic and xenogeneic settings, causing proliferation in T cell subsets. Tregs showed immunosuppressive effects on T lymphocyte populations when co-cultured with CPCs. Post infarction, CPCs were transplanted intramyocardially into an immune-competent mouse model 3 weeks after myocardial infarction. Human or murine Tregs were intravenously administered on transplantation day and three days later. Control groups received CPCs without Tregs or saline (PBS). CPCs with Tregs improved LV systolic function in three weeks, linked to reduced myocardial fibrosis and enhanced angiogenesis. This was accompanied by decreased splenocyte NK cell populations and pro-inflammatory cytokine levels in cardiac tissue. Treg therapy with CPC transplantation enhances cardiac functional and structural outcomes in mice. Though it does not directly avert graft rejection, it primarily affects NKG2D+ cytotoxic cells, indicating systemic immune modulation and remote heart repair benefits. Full article

Background/Objectives: Coeliac disease is an immune-mediated disorder of the gastrointestinal tract that may result in significant nutritional deficiencies. Effective management requires strict, lifelong adherence to a gluten-free diet. Both underdiagnosis and unnecessary dietary restrictions can adversely affect patients’ health and quality of life. To assess adherence to the current recommendations for the laboratory diagnosis of coeliac disease and promote evidence-based practices while reducing inter-laboratory variability, the Spanish Group on Autoimmunity of the Spanish Society of Immunology conducted a nationwide survey. Methods: A thirty-item survey was distributed to fifty autoimmune laboratories across Spain. Data were collected through a structured Excel-based questionnaire comprising multiple-choice items, which was distributed via email to the participating laboratories. It explored practices related to the diagnosis of coeliac disease in the general population and among at-risk groups as well as approaches to patient follow-up and demand management. Results: Thirty-five laboratories completed the electronic questionnaire. For the serological screening of coeliac disease, all the respondents reported using IgA anti-tissue transglutaminase (tTG-IgA) antibody testing together with total IgA measurement to assess IgA competence. However, consistent use of anti-endomysial antibody testing and HLA genotyping and adherence to pre-analytical recommendations for accurate interpretation of results were not uniform across centres. Conclusions: At the time these data were collected (the third trimester of 2021), the 2020 ESPGHAN guidelines for the diagnosis of coeliac disease in the paediatric population had not yet been fully implemented in most of the laboratories surveyed. For diagnosing adults, most laboratories adhered to local and European guidelines. Full article

Viral evasion from effective human immunodeficiency virus type 1 (HIV-1)-specific CD8+ T-cell responses and from antiretroviral therapy through viral sequence variation is frequently accompanied by a loss in viral fitness. The impact of sequence variations on replication capacity in vitro was mostly studied by introducing single mutations into a specific clonal strain such as NL4-3. How the specific viral backbone itself impacts replicative fitness remains elusive. To test for a potential effect of the viral backbone, we constructed HIV-1 clade B clones with consensus sequences for gag and/or pol and evaluated the infectivity of viral variants harboring well-defined cytotoxic T-lymphocyte (CTL) escape mutations or drug resistance mutations within this backbone or the clonal NL4-3 strain. Viral variants with consensus sequences were replication-competent in vitro, although at lower rates than the NL4-3 virus. Introduction of the dominant CTL escape mutation R₂₆₄K into the newly constructed viruses or into NL4-3 led to a dramatic reduction in infection rates. In contrast to the NL4-3 backbone, the combination of R₂₆₄K with its compensatory mutation S₁₇₃A on the consensus backbone led to higher infection rates as compared to the same virus in the absence of R₂₆₄K and S₁₇₃A. Furthermore, 2 out of 10 drug resistance mutations in pol led to opposing effects, with an increase in infection rates on the consensus gag/pol backbone and a reduction on NL4-3. Therefore, the effect of the respective viral backbone on infectivity observed in vitro might constitute an additional factor to explain differential kinetics of mutational evasion from immune and pharmaceutical pressure. Full article

Background/Objectives: CD47 is a cell surface glycoprotein moderately expressed in healthy cells and upregulated in cancer and viral infected cells. CD47’s interaction with signal regulatory protein alpha (SIRPα) inhibits phagocytic cells and its interaction with thrombospondin-1 inhibits T cell response. Experimental evidence has revealed that the blockade of CD47 resulted in the increased activation and function of both innate and adaptive immune cells, therefore exerting antitumoral and antiviral effects. Recent studies have shown that the combination of vaccines and immune checkpoint inhibitors could be a promising approach to increasing vaccine immunogenicity. Here, we investigated the vaccinal effect of anti-CD47 antibodies and discussed the possibilities of combining anti-CD47 treatments with vaccines. Methods: Using vesicular stomatitis virus (VSV), a widely used replication-competent vaccine vector, we evaluated the impact of the immunotherapeutic blockade of CD47 on cellular, humoral, and protective immunity. We infected C57BL/6 mice with VSV, treated them with anti-CD47 antibodies or an isotype, and evaluated the total immunoglobulin (Ig), IgG neutralizing antibodies, B cell activation, CD8+ T cell effector function, and survival of the mice. Results: We found that the treatments of anti-CD47 antibodies led to significantly increased Ig and IgG neutralizing antibody levels compared to the isotype treatment. Flow cytometric analysis of B cells revealed no difference in the number of circulating B cells; however, we observed an increased surface expression of CD80 and CD86 in B cells among anti-CD47-treated mice. Further analysis of the impact of CD47 blockade on T immunity revealed a significantly higher percentage of IFN-γ⁺ CD4 and IFN-γ⁺ CD8 T cells in anti-CD47-treated mice. Upon infecting mice with a lethal VSV dose, we observed a significantly higher survival rate among the anti-CD47-treated mice compared to control mice. Conclusions: Our results indicate that anti-CD47 treatment induces a stronger cellular and humoral immune response, leading to better protection. As such, immunotherapy by CD47 blockade in combination with vaccines could be a promising approach to improve vaccine efficacy. Full article

Background: Cryptococcus species constitute opportunistic fungi that seldom cause infections in individuals with competent immune systems. In the rare case of cryptococcal endocarditis, the fungus infiltrates the endocardium. This disease occurs almost exclusively in patients with active immunosuppression, implanted cardiac devices, or prosthetic valves. Objectives: This study aims to analyze all documented cases of Cryptococcus spp. endocarditis in humans, emphasizing the epidemiology, microbiology, clinical manifestations, therapeutic approaches, and infection outcomes. Methods: A comprehensive review was performed by searching the PubMed and Scopus databases. Results: A total of 16 studies reported data on 16 patients diagnosed with cryptococcal endocarditis. The mean patient age was 46.6 years, with males comprising 81.25% of cases. Immunosuppression was the most prevalent predisposing factor (31.25%), followed by a history of end-stage renal disease and prosthetic cardiac valves (25%). The most commonly affected intracardiac sites were the mitral (60%) and aortic valve (46.6%), while in 33.3% of cases, multiple-valve infection was observed. Cryptococcus neoformans was detected as the causative organism in the majority of cases (87.5%). The most frequently administered antifungal treatments included amphotericin B (87.5%) and fluconazole (43.75%), with combination therapy used in 62.5% of cases. Overall mortality was relatively high at 56.25%, with 50% of deaths directly attributed to the infection. Conclusions: Considering the ability of Cryptococcus spp. to induce severe systemic infections, healthcare providers should consider this pathogen in the differential diagnosis when yeast microorganisms are identified in microbiological samples. This is particularly crucial for patients with underlying comorbidities or immunodeficiency, as early recognition is crucial to ensure precise diagnosis and treatment. Full article

Neutrophil extracellular trap (NET) formation is a process known as NETosis and is a critical innate immune response mechanism that can become pathologically dysregulated in various inflammatory, autoimmune, infectious, and neoplastic diseases. Reactive oxygen species (ROS) play a central role in NETosis induction, making antioxidants a promising therapeutic approach. This review outlines the molecular mechanisms underlying NET formation and highlights three principal antioxidant-based inhibitory strategies: NADPH oxidase (NOX) inhibition, ROS scavenging, and myeloperoxidase (MPO) inhibition. Evidence supports the use of agents such as diphenylene iodonium (NOX inhibitor), N-acetylcysteine and glutathione (ROS scavengers), and thiocyanate (MPO inhibitor), which significantly reduce NETosis in vitro and in vivo. Moreover, natural compounds like resveratrol show pleiotropic effects by modulating neutrophil activation, ROS production, and protease activity. Combination therapies that enhance total antioxidant capacity are particularly effective, though their translation to clinical practice faces challenges such as stimulus specificity, bioavailability, and maintaining immune competence. Antioxidant-based therapies thus represent a promising avenue for targeted NETosis modulation. Future research should focus on improving delivery systems, identifying NET-specific biomarkers, and integrating antioxidants into broader immunomodulatory strategies. Full article