Search Results (3,269)

Inflammatory bowel disease (IBD) is a chronic immune-mediated condition of the gastrointestinal tract, characterized by dysregulated inflammatory responses throughout the gastrointestinal tract. It includes two major phenotypes, Crohn’s disease (CD) and ulcerative colitis (UC), which present with varying gastrointestinal and systemic symptoms. The pathophysiology of IBD is multifactorial including genetic predisposition, mucosal and epithelial dysfunction, environmental injury, and both innate and adaptive immune response abnormalities. Several predisposing genetic factors have been associated with IBD explaining the strong hereditary risk for both CD and UC. For example, Caspase Recruitment Domain 9 (CARD9) variant rs10781499 increases risk for IBD, while other variants are specific to either CD or UC. CD is related to loss-of-function mutations in the nucleotide oligomerization domain containing the protein 2 (NOD2) gene and Autophagy-Related 16-like 1 (ATG16L1) gene. UC risk is increased particularly in Chinese populations by the A-1661G polymorphism of the Cytotoxic T-lymphocyte antigen 4 (CTLA-4) gene. This abnormal CTLA-4 interferes with B- and T-cell responses causing predisposition to autoimmune conditions. Previous studies suggested that IBD results from breakdown of the adaptive immune system, primarily of T-cells. However, new evidence suggests that a primary breakdown of the innate immune system in both CD and UC increases susceptibility to invasion by viruses and bacteria, with a compensatory overactivation of the adaptive immune system as a result. When this viral and microbial invasion continues, further damage is incurred, resulting in a downward cycle of further cytokine activation and epithelial damage. Released biomarkers also affect the permeability of the epithelial membrane, including lactoferrin, nitric oxide (NO), myeloperoxidase (MPO) and its activation of hypochlorous acid, matrix metalloproteinases (MMPs), especially MMP-9, omentin-1, and others. Increased macrophage and dendritic cell dysfunction, increased neutrophil activity, increased numbers of innate lymphoid cells, increased T-cells with decreased regulatory T-cells (Tregs), and changes in B-cell populations and immunoglobulin (Ig) functions are all associated with IBD. Finally, treatment of IBD has typically consisted of medical management (e.g., aminosalicylates and corticosteroids) and lifestyle modification, and surgical intervention in extreme cases. New classes of medications with more favorable side effect profiles include anti-integrin antibodies, vedolizumab, etrolizumab, and carotegrast methyl. Additionally, fecal microbiota transplant (FMT) is a newer area of research for treatment of IBD along with TNF-blockers, JAK inhibitors, and S1PR modulators. However, expense and long preparation time have limited the usefulness of FMT. Full article

A reassessment of the risk-benefit balance of the two lipid nanoparticle (LNP)-based vaccines, Pfizer’s Comirnaty and Moderna’s Spikevax, is currently underway. While the FDA has approved updated products, their administration is recommended only for individuals aged 65 years or older and for those aged 6 months or older who have at least one underlying medical condition associated with an increased risk of severe COVID-19. Among other factors, this change in guidelines reflect an expanded spectrum and increased incidence of adverse events (AEs) and complications relative to other vaccines. Although severe AEs are relatively rare (occurring in < 0.5%) in vaccinated individuals, the sheer scale of global vaccination has resulted in millions of vaccine injuries, rendering post-vaccination syndrome (PVS) both clinically significant and scientifically intriguing. Nevertheless, the cellular and molecular mechanisms of these AEs are poorly understood. To better understand the phenomenon and to identify research needs, this review aims to highlight some theoretically plausible connections between the manifestations of PVS and some unique structural properties of mRNA-LNPs. The latter include (i) ribosomal synthesis of the antigenic spike protein (SP) without natural control over mRNA translation, diversifying antigen processing and presentation; (ii) stabilization of the mRNA by multiple chemical modification, abnormally increasing translation efficiency and frameshift mutation risk; (iii) encoding for SP, a protein with multiple toxic effects; (iv) promotion of innate immune activation and mRNA transfection in off-target tissues by the LNP, leading to systemic inflammation with autoimmune phenomena; (v) short post-reconstitution stability of vaccine nanoparticles contributing to whole-body distribution and mRNA transfection; (vi) immune reactivity and immunogenicity of PEG on the LNP surface increasing the risk of complement activation with LNP disintegration and anaphylaxis; (vii) GC enrichment and double proline modifications stabilize SP mRNA and prefusion SP, respectively; and (viii) contaminations with plasmid DNA and other organic and inorganic elements entailing toxicity with cancer risk. The collateral immune anomalies considered are innate immune activation, T-cell- and antibody-mediated cytotoxicities, dissemination of pseudo virus-like hybrid exosomes, somatic hypermutation, insertion mutagenesis, frameshift mutation, and reverse transcription. Lessons from mRNA-LNP vaccine-associated AEs may guide strategies for the prediction, prevention, and treatment of AEs, while informing the design of safer next-generation mRNA vaccines and therapeutics. Full article

Bacterial lysates have emerged as promising immunomodulatory agents that can enhance innate immune responses. Given the crucial role of macrophages in recognizing and controlling intracellular pathogens such as Mycobacterium tuberculosis, this study aimed to evaluate the immunological effects of selected bacterial lysates on human monocyte-derived macrophages (MDMs). We examined the ability of commercial bacterial lysates, Pulmonarom, Ismigen, Uro-Vaxom, and a lysate of M. tuberculosis H37 Ra (LMtb) to stimulate the production of key pro-inflammatory cytokines, including TNF-α, IL-1β, and IL-8. In addition, we investigated whether these lysates could modulate the expression of bactericidal/permeability-increasing protein (BPI), a critical antimicrobial effector, and assessed their ability to reduce the intracellular burden of mycobacteria and induce autophagy. The results demonstrate diverse immunostimulatory profiles among the lysates, highlighting differences in both inflammatory and antimicrobial responses that may be relevant for host-directed therapeutic strategies against tuberculosis. Notably, beyond the in vitro antimycobacterial activity observed for BPI, this protein was also found to be elevated in both serum and bronchoalveolar lavage fluid from patients with active TB, reflecting local and systemic immune activation. Furthermore, the reduction in BPI levels after treatment suggests its potential utility for following the dynamics of infection. Full article

Excessive production of type I interferons (IFNs) underlies the immunopathogenesis of autoimmune disorders, including systemic lupus erythematosus and autoimmune pancreatitis. Whether type I IFNs play pathogenic or protective roles in the development of inflammatory bowel diseases (IBD) has been a matter of debate. The production of type I IFNs is tightly regulated by the conjugation and removal of polyubiquitin chains on or from intracellular signaling molecules. OTU deubiquitinases 3 (OTUD3) and 5 (OTUD5) are enzymes that cleave various polyubiquitin chains from target proteins. OTUD3 and OTUD5 deubiquitinate key critical intracellular molecules of the type I IFN signaling pathways, stimulator of interferon genes (STING), and TNF receptor-associated factor 3 (TRAF3), respectively, and thus regulate the production of type I IFNs by innate immune cells. Recent studies provided evidence that the impaired function of OTUD3 and OTUD5 increases susceptibility to human and experimental IBD owing to the excessive production of type I IFNs caused by the activation of STING and TRAF3, respectively. Collectively, OTUD3 and OTUD5 play protective rather than pathogenic roles in the development of IBD through the negative regulation of type I IFN-mediated signaling pathways. In this review article, we discuss the association between the development of IBD and impaired function of OTUD3 or OTUD5 by focusing on their deubiquitinase activity and type I IFN responses. Full article

Hypertension affects over 1.39 billion people globally, causing 9.4 million deaths annually. This paper examines the intricate relationship between the immune system and hypertension, highlighting the contributions of both innate and adaptive immune responses. The innate response, involving natural killer (NK) cells, macrophages, toll-like receptors (TLRs), and dendritic cells, contributes to organ damage and inflammatory responses, exacerbating hypertension. Adaptive immunity, particularly T cells, further exacerbates vascular and renal dysfunction through the release of cytokines such as IFN-γ, IL-17A, and TNF-α, ultimately leading to multisystem damage. Therapeutic strategies targeting these immune responses are being explored, including immunosuppressants such as mycophenolate mofetil (MMF) and methotrexate (MTX), as well as monoclonal antibodies against IL-1β and TNF-α. While these strategies show promise, further research is needed to evaluate their efficacy and safety. Furthermore, this paper highlights the potential benefits of immunological approaches in managing the root causes of hypertension, offering an alternative to conventional therapies focused on the renin–angiotensin–aldosterone system. In conclusion, this work highlights the immune mechanisms in the hypertension pathogenesis, identifying them as potential therapeutic targets for enhanced management and improved patient outcomes. Full article

Interferons (IFNs) are key cytokines at the intersection of innate and adaptive immunity. While their antiviral and antitumor roles are well recognized, emerging evidence implicates IFNs—particularly types I, II, and III—in the initiation and progression of autoimmune diseases (ADs). This review synthesizes current data on IFN biology, their immunoregulatory and pathogenic mechanisms, and their contributions to distinct AD phenotypes. We conducted a comprehensive review of peer-reviewed literature on IFNs and autoimmune diseases, focusing on publications indexed in PubMed and Scopus. Studies on molecular pathways, immune cell interactions, disease-specific IFN signatures, and clinical correlations were included. Data were extracted and thematically organized by IFN type, signaling pathway, and disease context, with emphasis on rheumatic and systemic autoimmune disorders. Across systemic lupus erythematosus, rheumatoid arthritis, Sjögren’s syndrome, systemic sclerosis, idiopathic inflammatory myopathies, multiple sclerosis, type 1 diabetes, psoriasis, and inflammatory bowel diseases, IFNs were consistently associated with aberrant activation of pattern recognition receptors, sustained expression of interferon-stimulated genes (ISGs), and dysregulated T cell and B cell responses. Type I IFNs often preceded clinical onset, suggesting a triggering role, whereas type II and III IFNs modulated disease course and severity. Notably, IFNs exhibited dual immunostimulatory and immunosuppressive effects, contingent on tissue context, cytokine milieu, and disease stage. IFNs are central mediators in autoimmune pathogenesis, functioning as both initiators and amplifiers of chronic inflammation. Deciphering the context-dependent effects of IFN signaling may inform targeted therapeutic strategies and advance precision immunomodulation in autoimmune diseases. Full article

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease in which environmental factors modulate genetically determined immune dysregulation. Vitamin D has emerged as a plausible modifier of disease expression because its active metabolite signals through the vitamin D receptor on innate and adaptive immune cells and influences antigen presentation, cytokine balance, and lymphocyte differentiation. This narrative review synthesizes current evidence on vitamin D status and supplementation in SLE with attention to organ-specific domains. Observational studies consistently report high rates of hypovitaminosis D in SLE and associations with less favorable clinical profiles, including higher global and renal disease activity, adverse cardiometabolic features, greater infection vulnerability, and neuropsychiatric manifestations. Preclinical models demonstrate neuroprotective and barrier-stabilizing actions of vitamin D analogs, supporting biological plausibility. Interventional trials indicate that supplementation safely corrects deficiency and shows signals of benefit for selected outcomes (e.g., modest activity reductions or fatigue in specific contexts), although effects on interferon signatures, complement, and autoantibodies are heterogeneous and often limited. Overall, current evidence supports optimization of vitamin D status as a low-risk adjunct in comprehensive SLE care while highlighting the need for adequately powered, organ-focused randomized trials using standardized measurements and prespecified endpoints to define causality, therapeutic targets, and long-term safety. Full article

Gliomas present as highly heterogeneous and aggressive central nervous system (CNS) tumors with challenging diagnosis and management. Traditional and current therapies are lacking efficacy in overcoming the complex and dynamic behavior of gliomas and the local tumor microenvironment. Emerging research highlights the significant role of innate immune receptors including Toll-like, NOD-like and RIG-like receptors, as well as cGAS-STING receptors, scavenger and C-type lectin receptors in glioma development and progression. These receptors can both impact immune modulation as well as facilitate tumor growth through interactions with tumor-associated macrophages, myeloid-derived suppressor cells and cytokine networks, contributing to immune evasion in the tumor microenvironment. Herein, we discuss the main signaling pathways induced through innate immune receptors in gliomas along with their functional properties in glioma pathology while exploring current applications to treatment. Utilizing innate immune receptors as therapeutic targets holds great promise, especially when used along with traditional chemotherapy and radiation schemes, strengthening immune responses. Future studies focusing on the deeper understanding of innate immune receptors signaling and complexity are highly required to enable novel immunoregulatory treatment schemes for gliomas. Full article

Local recurrence after breast cancer surgery presents a critical challenge, demanding novel local immunotherapies capable of eliminating residual disease while avoiding systemic toxicity. In situ-forming hydrogels, functionalized with bioactive cargoes, represent a promising platform for precise spatiotemporal drug delivery directly into the post-resection tumor microenvironment. This review comprehensively examines the core design principles governing these advanced materials, highlighting their biocompatibility, stimuli-responsive behavior, tunable mechanics for conforming to surgical cavity, and capacity for multifunctional integration. A key mechanism discussed is how this controlled release profile orchestrates a temporal progression from innate immune activation to robust adaptive immunity. Despite significant promise, translational success faces substantial hurdles, including efficacy validation, scalable manufacturing, regulatory pathway definition, and the lack of predictive biomarkers. Future research priorities include optimizing drug/antigen release kinetics, establishing standardized characterization methods for complex biohybrid systems, and designing adaptive clinical trials incorporating detailed immunomonitoring. By integrating functional biomaterials with immuno-oncology, in situ-forming hydrogels offer a paradigm-shifting approach for postoperative cancer treatment. This review provides a strategic roadmap to accelerate their translation from bench to bedside. Full article

Background: Most immunologically “cold” tumors do not respond durably to checkpoint blockade because tumor antigen (TA) release and presentation are insufficient to prime effective T-cell immunity. While prior work demonstrated synergy between cisplatin and a TLR7/8/9 agonist (CR108) in 4T1 tumors, the underlying mechanism—particularly whether chemotherapy functions as a broad antigen-releasing agent enabling TLR-driven immune amplification—remained undefined. Methods: Using murine models of breast (4T1), melanoma (B16-F10), and colorectal cancer (CT26), we tested multiple chemotherapeutic classes combined with CR108. We quantified intratumoral and systemic soluble TAs, antigen presentation and cross-priming by antigen-presenting cells, tumor-infiltrating lymphocytes, and cytokine production by flow cytometry/ICS. T-cell receptor β (TCRβ) repertoire dynamics in tumor-draining lymph nodes were profiled to assess amplitude and breadth. Tumor microenvironment remodeling was analyzed, and public datasets (e.g., TCGA basal-like breast cancer) were interrogated for expression of genes linked to TA generation/processing and peptide loading. Results: Using cisplatin + CR108 in 4T1 as a benchmark, we demonstrate that diverse chemotherapies—especially platinum agents—broadly increase the repertoire of soluble tumor antigens available for immune recognition. Across regimens, chemotherapy combined with CR108 increased T-cell recognition of candidate TAs and enhanced IFN-γ⁺ CD8⁺ responses, with platinum agents producing the largest expansions in soluble TAs. TCRβ sequencing revealed increased clonal amplitude without loss of repertoire breadth, indicating focused yet diverse antitumor T-cell expansion. Notably, therapeutic efficacy was not predicted by canonical damage-associated molecular pattern (DAMP) signatures but instead correlated with antigen availability and processing capacity. In human basal-like breast cancer, higher expression of genes involved in TA generation and antigen processing/presentation correlated with improved survival. Conclusions: Our findings establish an antigen-centric mechanism underlying chemo–TLR agonist synergy: chemotherapy liberates a broadened repertoire of tumor antigens, which CR108 then leverages via innate immune activation to drive potent, T-cell-mediated antitumor immunity. This framework for rational selection of chemotherapy partners for TLR7/8/9 agonism and support clinical evaluation to convert “cold” tumors into immunologically responsive disease. Full article

Rabies, a zoonotic infectious disease causing central nervous system inflammation, remains a threat to public health in regions with limited medical resources. Vaccination effectively reduces rabies incidence and mortality, underscoring the need for vaccines that are cost-effective, immunogenic, protective, and safe. This study constructed a recombinant rabies virus (rRABV)-overexpressing glucocorticoid-induced tumor necrosis factor receptor ligand (GitrL), named rLBNSE-GitrL, using a reverse genetic operating system. rLBNSE-GitrL exhibited similar in vitro phenotypic characteristics and immune safety as the parent RABV (rLBNSE). This recombinant virus stimulated the production of a greater number of activated dendritic cells (DCs) compared to rLBNSE. The enhanced innate immune response induced by rLBNSE-GitrL may be mediated through the activation of innate immune-related signaling pathways, such as the tumor necrosis factor (TNF), and chemokine signaling pathways, and the upregulation of a series of innate immune-related genes, including MMP2, IL-6, CXCL9, TIMP1, IL-17d, and TNF-α. Consequently, rLBNSE-GitrL elicited significantly higher levels of RABV vaccine-induced virus-neutralizing antibodies (VNA), IgG, and IgM compared to rLBNSE as early as 3 days post-immunization (dpi), thereby improving the protective effect in mice. Collectively, the overexpression of GitrL facilitated the induction of early and potent antibody responses following RABV immunization. Full article

The interaction between microorganisms in the dental microfilm (plaque) at the gingival margin, the immune system, and the brain is vital for gingival health. The brain constantly receives information regarding microbial composition and inflammation status through afferent nerves and the bloodstream. It modulates immune responses via efferent nerves and hormonal systems to maintain homeostasis. This relationship determines whether the gingiva remains healthy or develops into gingivitis (non-destructive inflammation) or periodontitis (a destructive condition), collectively referred to as periodontal disease. Factors associated with severe periodontitis heighten the responsiveness of this homeostatic system, diminishing the adaptive immune system’s defence against symbiotic microorganisms with pathogenic properties, known as pathobionts. This leads to excessive innate immune system activation, effectively preventing infection but damaging the periodontium. Consequently, investigating the microbiota–brain axis is vital for understanding its impact on periodontal health and disease. Herein, we examine recent advancements in how the defence against pathobionts is organised within the brain, and how it regulates and adapts the pro-inflammatory and anti-inflammatory immune balance, controlling microbiota composition. It also discussed how pathobionts and emotional stress can trigger neurodegenerative diseases, and how inadequate coping strategies for managing daily stress and shift work can disrupt brain circuits linked to immune regulation, weakening the adaptive immune response against pathobionts. Full article

Neutrophils are an essential protective component of the innate immune system. However, in severe bacterial infections, neutrophils are known to mis-localise from the primary site of infection to other organs, where excessive release of cytokines, chemokines, and neutrophil extracellular traps (NETs) can induce organ damage and death. In this study, we use an animal model of bacterial infection originating in the peritoneum to show that hydrogen peroxide (H₂O₂, a potent neutrophil chemoattractant) is initially released in high concentrations both in the peritoneum and in multiple ‘off-target’ organs (lungs, liver and kidneys). The initial high H₂O₂ release inhibits neutrophil chemotaxis, but after 24 h concentrations of H₂O₂ reduce and can promote neutrophil migration to organs, where they release pro-inflammatory cytokines and chemokines along with NETs. The antimalarial compound artesunate potently inhibits neutrophil migration to off-target organs. It also abolishes cytokine, chemokine, and NET production, suggesting that artesunate may be a valuable novel therapy for preventing off-target organ inflammation associated with severe bacterial infections. Finally, the potency of H₂O₂ as a chemoattractant is shown by in vitro experiments in which, faced with competing gradients of H₂O₂ and other chemoattractants, neutrophils preferentially migrate towards H₂O₂. Full article

Background/Objectives: This review article highlights the role of the nucleotide-binding domain, leucine-rich repeat, pyrin domain-containing 3 protein (NLRP3) inflammasomes in various gastrointestinal and hepatic disorders in the pediatric age group. NLRP3 inflammasomes are one of the principal intracellular innate immune sensors. During inflammation, molecules such as caspase-1 and the release of IL-1β and IL-18 are produced. The NLRP3 inflammasome participates in the preservation of intestinal homeostasis and mucosal immune response. The objective is to evaluate the published articles related to the role of NLRP3 inflammasomes in common pediatric gastrointestinal and hepatic disorders in order to identify the future perspective regarding their possible therapeutic values. Methods: We searched Medline for NLRP3 inflammasomes and disorders of the digestive system during childhood. Results: Although the majority of articles were related to various disorders of adults, such as Alzheimer’s disease, Parkinson’s disease, atherosclerosis, as well as neurodevelopmental disorders, such as schizophrenia, a few published datasets were related to the roles of NLRP3 in the pediatric age group: they addressed autism, rheumatoid arthritis, and other autoimmune diseases, as well as inflammatory bowel diseases (IBD) and hepatic infection. Some research demonstrated that the NLRP3 inflammasome has a protective role; however, it also has a pathogenic function. Conclusions: This review focused on the comprehensive role of inflammasome NLRP3 in the most common pediatric and neonatal gastrointestinal and hepatic diseases, including clinical and experimental studies, as well as the pharmacological inhibitors for NLRP3 inflammasomes, which may provide future therapy for GIT problems, such as IBD. Full article

Sindbis virus (SINV) is a mosquito-borne alphavirus capable of causing neurological and immunological symptoms in humans, yet its effects on neural/immune systems remain insufficiently characterized. This study aimed to examine SINV replication, UV-C light inactivation, apoptosis induction, and immune gene modulation in human SH-SY5Y neuroblastoma cells. Following viral adaptation and infectious dose determination, SINV replication and inactivation were assessed using RT-qPCR and dsRNA immunofluorescence. Apoptotic markers (caspase-3, Bax, Bcl-2) were analyzed by immunofluorescence and immune genes expression kinetics (TLR3/7, RIGI, MDA5, IL-1β, IL-6, TNFα, IL-10, IFNβ and β-catenin) were measured at defined time points post-infection by RT-qPCR. SH-SY5Y cells supported productive SINV infection, with viral RNA detectable as early as 3 hpi and marked cytopathic effects by 24 hpi. A custom-built UV-C chamber achieved complete viral inactivation following 3 × 30 s exposures. We observed SINV time-course replication and UV-C inactivation with conspicuous morphological alterations in SH-SY5Y cells. Furthermore, SINV triggered caspase-dependent apoptosis and robust transcriptional upregulation of innate immune genes, peaking between 12–16 hpi and declining by 30 hpi. These findings elucidate the temporal dynamics of SINV replication, cell death mechanisms, and immune activation in a neuronal context, contributing to a better understanding of SINV neuropathogenesis. Full article