Search Results (344)

Severe fever with thrombocytopenia syndrome (SFTS) is a newly discovered tick-borne disease caused by SFTS virus (SFTSV) infection. Patients present with high fever, thrombocytopenia, and multiple organ dysfunction, with a high mortality rate and a lack of specific treatment, all of which indicate that research on the deterioration mechanism and treatment of this disease is urgent. Currently, multiple studies have indicated that cytokine storm is one of the core factors contributing to the deterioration of the disease. SFTSV inhibits the host’s type I interferon response through its non-structural protein NSs, thereby promoting immune evasion and viral replication. Extensive viral stimulation leads to dysfunction and abnormal polarization of immune cells (including monocytes, macrophages, dendritic cells, T cells, and B cells), triggering the massive release of pro-inflammatory factors(such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and interleukin-1 beta (IL-1β)), anti-inflammatory factors (such as interleukin-10 (IL-10)), and chemokines(such as interferon-gamma inducible protein 10 (IP-10), monocyte chemoattractant protein-1 (MCP-1), and interleukin-8 (IL-8)). This cytokine storm exacerbates the imbalance between pro-inflammatory and anti-inflammatory factors, as well as immune paralysis, leading to vascular endothelial damage, microthrombosis, and ultimately, multi-organ failure, which determines the clinical outcome. Simultaneously, specific cytokines and immune cell phenotypes can serve as biomarkers for disease severity and prognosis. In terms of treatment, this article further summarizes the intervention strategies targeting the aforementioned immune links, including intravenous immunoglobulin (IVIG), tocilizumab (targeting the IL-6 receptor), inhibitors of Janus kinase (JAK) and nuclear factor-kappa B (NF-κB) signaling pathways, interferon, neutralizing antibodies, and other immunotherapy methods. By analyzing the dynamic changes and mechanisms of cytokine storm in the course of SFTS, and summarizing current potential immunotherapy methods, this article aims to provide a theoretical framework for the future treatment of SFTS. Full article

Vernal keratoconjunctivitis (VKC) represents far more than a typical allergic eye disease. It is a distinct and often underestimated chronic inflammatory condition that primarily affects children during critical stages of physical and emotional development. Though frequently grouped with seasonal allergic conjunctivitis, VKC differs significantly in its immunopathology, clinical presentation, and long-term implications. Its intense ocular symptoms and its potential for corneal damage and substantial psychosocial burden require, rather than symptom control, coordinated and multidisciplinary management. This narrative review explores VKC from every angle, with a particular focus on its implications for pediatric care. VKC, in fact, represents a genuine clinical challenge: as its symptoms can mimic milder forms of conjunctivitis, its course is often unpredictable, and its treatment requires balancing efficacy and safety in vulnerable age groups. We examined the immunological mechanisms that make it a model of localized Th2 inflammation, the diagnostic pitfalls that delay recognition, and the evolving treatment landscape, from conventional therapies like cyclosporine A and tacrolimus to innovative agents such as omalizumab and dupilumab. We also highlighted the role of emerging biomarkers, the influence of environmental and microbiome factors, and the urgent need for standardized care pathways. As research continues to expand our understanding, VKC is emerging as a prime example of how personalized medicine and translational science can intersect to address complex immune-mediated diseases in children. For the ones treating pediatric allergic disorders, VKC is no longer a rare curiosity: it is a clinical challenge worth understanding deeply. Full article

Food allergy is an exaggerated immune response, mediated by Immunoglobulin E (IgE) or by cells, to food antigens. Dogs and cats may present with both dermatological and gastrointestinal manifestations, although non-seasonal pruritus is the most common clinical sign. Despite advances in understanding the immunopathogenesis of this condition, the elimination–provocation test remains the gold standard for diagnosis. However, new diagnostic approaches, like molecular allergen macroarrays and lymphocyte proliferation assays, may complement traditional strategies, opening new perspectives for accurate diagnosis. For long-term management, strict avoidance of offending allergens is essential, but emerging therapeutic interventions, including immunotherapy using food components and targeted modulation of the gut–skin axis, are promising for improving clinical outcomes. This review summarizes current knowledge and highlights innovative approaches that can transform the diagnosis and management of food allergy in companion animals. Full article

Autoimmune ocular surface diseases represent a complex group of disorders in which systemic immune dysregulation triggers chronic inflammation, epithelial dysfunction, and progressive tissue fibrosis. Systemic lupus erythematosus, primary Sjögren’s syndrome, and ocular cicatricial pemphigoid are the principal entities linking systemic autoimmunity to ocular surface pathology. These conditions share convergent mechanisms—including dysregulated cytokine signaling (IFN-I, IL-6, and IL-17), complement activation, and epithelial–mesenchymal transition—culminating in tear film instability and visual impairment. Recent advances in molecular immunology and omics profiling have elucidated disease-specific pathways and identified actionable therapeutic targets. Conventional immunosuppressants such as corticosteroids and cyclosporine remain fundamental, yet emerging biologics targeting BAFF, IFNAR, and JAK/STAT signaling—alongside regenerative strategies employing mesenchymal and induced pluripotent stem cells—are transforming disease management. Parallel innovations in amniotic membrane transplantation, keratoprosthesis, and bioengineered corneal scaffolds integrate structural reconstruction with immune modulation. Furthermore, the convergence of multi-omics analytics, artificial intelligence-assisted diagnostics, and microbiome-based immunomodulation heralds a new era of precision ophthalmology. This review synthesizes current molecular insights, clinical observations, and translational advances that collectively redefine autoimmune ocular surface diseases—from chronic inflammatory disorders into a targetable, regenerative, and potentially reversible spectrum of conditions. Full article

Background/Objective: Long COVID is an important cause of disability following SARS-CoV-2 infection; yet, its underlying mechanisms are not completely understood. One proposed mechanism is the long-lasting dysregulation of the immune complement system. This systematic review is the first to summarize the current evidence and evaluate the potential role of long-lasting complement activation in people with long COVID. Methods: A systematic electronic search on PubMed, MEDLINE, CINAHL, and Embase was conducted up to 15 October 2025, to identify studies investigating complement activation in people with the post-COVID-19 condition. The Newcastle–Ottawa Scale was used to evaluate the risk of bias and methodological quality. Results: Among the 247 studies initially identified, eleven met the inclusion criteria, comprising 1435 individuals (age: 48.5 years, 70% females) with long COVID and 1124 controls (age: 43.6 years, 60% females). All studies were of a high quality, with scores ranging from 7 to 8 stars (mean: 7.6 ± 0.5). The activation of the classical complement pathway was investigated in nine studies, whereas the lectin, alternative, and terminal complement pathways were each assessed in three studies. Multiple studies investigated several complement pathways. The results were heterogeneous since several markers of complement activation spanning the classical (C2, C4a, C4b, and C1s-C1INH), alternative (Ba, iC3b, and Factor D), and terminal (C5bC6, C5a, C9, and TCC) pathways were elevated, whereas other markers were not significantly different (C3, C4, and C4d) between patients with/without long COVID. In addition, markers spanning the lectin complement pathway (MBL, and MASP1-C1INH) were not significantly different between individuals with and without long COVID. Conclusions: The current evidence suggests potential long-lasting complement system dysregulation in individuals with long COVID, although the clinical significance remains controversial, due to heterogenous findings. Specific post-COVID symptom clusters, such as fatigue, dyspnea, or brain fog, have been linked to a distinct pattern of complement dysregulation. Substantial methodological heterogeneity, including differences in follow-up periods, complement markers, assessment methods, and control groups, along with the small number of available studies, underscores the need for further research to clarify the mechanisms linking complement dysregulation to long COVID. Full article

Mycobacterium bovis is the causative agent of tuberculosis (TB) infecting a wide range of animal hosts, including humans. Domestic pigs (Sus scrofa domestica) are susceptible to different mycobacteria, particularly species within the Mycobacterium avium complex (MAC). However, in countries where bovine TB is endemic, such as Argentina, M. bovis is the most frequently reported species in pigs. This study aimed to evaluate the immune response and disease progression of a local strain (MB894) isolated from pigs and compare its pathogenicity with the highly virulent strain MB303, isolated from wild boar. Additionally, we sought to explore the genomic basis underlying the virulent phenotype of MB894. For this purpose, a murine infection model was used to assess pathogenicity, organ colonization, dissemination and cytokine induction. Whole-genome sequencing was performed to identify genetic features, including non-synonymous SNPs and INDELs, potentially associated with virulence. The severe immunopathogenesis produced by MB894, the higher multiplication rate in the evaluated organs, and the greater dissemination to other organs compared to MB303, combined with the cytokine levels induced by this strain, prompted us to classify MB894 as a hypervirulent strain. Genomic analysis revealed candidate genes that may be virulence factors contributing to this phenotype. In summary, MB894 represents a hypervirulent M. bovis strain with distinct pathogenic and genomic characteristics. These findings provide insights into the molecular determinants of virulence and highlight the need for further evaluation of identified gene candidates. Full article

Introduction: Neuropathic pain (NP) in neuromyelitis optica spectrum disorder (NMOSD) represents a significant and often under-recognized complication arising from central nervous system (CNS) lesions. Unlike other demyelinating disorders, NMOSD involves a distinct immunopathogenesis primarily driven by aquaporin-4 antibodies (AQP4-IgG), leading to severe inflammatory damage. NP is typically the consequence of inflammatory damage to the spinothalamic tract or dorsal columns, resulting in both acute and chronic pain syndromes. Methods: A systematic review and meta-analysis were conducted following a comprehensive search of Medline and Scopus, identifying nine eligible studies reporting on NP in NMOSD. Results: Pooled prevalence was estimated using a random-effects metaprop meta-analysis with Freeman–Tukey transformation and REML-based heterogeneity estimation. The pooled prevalence of NP among patients with NMOSD was 56.2% (95% CI: 41.7–70.1%; I² = 95.3%, p < 0.001). Sensitivity analysis including only AQP4-IgG⁺ cohorts revealed a prevalence of 63.2% (95% CI: 23.4–94.7%; I² = 98.1%, p < 0.001). No significant difference was found between mixed and AQP4-IgG⁺-only populations (53.05% vs. 63.27%, p = 0.63). Meta-regression showed no significant associations between NP prevalence and age (β = 0.01, p = 0.33) or disability (β = 0.08, p = 0.18). Qualitative synthesis demonstrated an association between thoracic spinal cord lesions and NP, and also indicated that NP was often resistant and refractory to standard pharmacologic therapies. Conclusions: NP affects one in two NMOSD patients, and is associated with thoracic spinal cord lesions. In comparison with multiple sclerosis, NP in NMOSD is primarily structural and immunopathological in origin. Treatment strategies remain inadequate, emphasizing the need for early recognition and a disease-specific therapeutic approach. Full article

Acute disseminated encephalomyelitis (ADEM) is a rare, immune-mediated demyelinating disorder of the central nervous system (CNS) that predominantly affects children and young adults. ADEM typically follows an infectious or, less commonly, immunization-related trigger, and despite decades of clinical observation, its etiopathogenesis remains only partially understood. Clinically, the diagnosis of ADEM continues to pose significant challenges due to the absence of disease-specific biomarkers and its clinical and radiological overlap with other acquired demyelinating syndromes. This narrative review aims to summarize and critically discuss current knowledge on ADEM, with particular emphasis on its etiopathogenesis and clinical characteristics, highlighting the potential implications of recent research for clinical practice and management of this disease. Particular emphasis is placed on post-infectious immune mechanisms, including molecular mimicry, blood–brain barrier (BBB) disruption, loss of immune tolerance, and neuroinflammatory cascades. A wide spectrum of infectious triggers—viral, bacterial, parasitic—as well as post-vaccination, post-transplantation, paraneoplastic, metabolic, and host-related genetic factors are discussed in the context of immune dysregulation leading to CNS demyelination. We also highlight characteristic clinical and neuroimaging features that may aid in differentiating ADEM from other demyelinating syndromes, while acknowledging current diagnostic limitations. The integration of recent advances in ADEM immunopathogenesis with established clinical and radiological insights underscores the complexity of this disorder and highlights the evolving nature of current concepts regarding its diagnosis and clinical heterogeneity. Full article

Experimental autoimmune uveitis (EAU) in rats is a pivotal model for understanding the immunological mechanisms of human uveitis and developing therapies. In humans, optical coherence tomography (OCT) allows for the in vivo detection of characteristic findings in active uveitis, as well as sequelae of inflammation. The objective of this study was to correlate OCT findings in patients with uveitis with retinal histologies from two rat models of EAU caused by T cells with different autoantigen specificities and well-known underlying immunological pathomechanisms. Patients with various noninfectious uveitis subtypes underwent imaging using an ultra-widefield swept source or conventional OCT. Histological cryosections from rat eyes with experimental autoimmune uveitis were stained for T cell and/or macrophage markers. Typical human OCT findings were reproduced in the experimental animal model. Hyperreflective signals observed on OCT corresponded to lymphocyte infiltration in histological sections. This infiltration was typically found as vasculitis in the perivascular regions and snowballs in the posterior hyaloid. There was lymphocyte and macrophage infiltration of the retina through the retinal vessels and the retinal pigment epithelium. Comparing in vivo OCT imaging of human uveitis with corresponding histologies from rat models improves our understanding of the type of inflammation, extent of tissue destruction, and immunopathogenesis. Full article

Background/Objectives: Allergic features of anisakiasis, caused by ingestion of third-stage larvae of Anisakis simplex via raw or undercooked fish, manifest clinically as acute gastroallergic anisakiasis (GAA) or chronic urticaria with Anisakis sensitization (CU+). Differentiating these clinical phenotypes remains challenging. This study aimed to evaluate the maturation and avidity of specific antibodies (IgE, IgG4, IgG, and IgA) as biomarkers for discriminating between acute and chronic forms of anisakiasis. Methods: A prospective cohort of 65 patients from Madrid, Spain, was classified into three groups: GAA (n = 22), CU+ (n = 22), and chronic urticaria without sensitization (CU−, n = 21). Serum samples were analyzed for antigen-specific immunoglobulins using ELISA and Western blot. Avidity indices (AIs) were quantified through urea dissociation assays. Statistical comparisons and correlation analyses were performed to associate antibody avidity with clinical phenotype and demographic variables. Results: GAA patients exhibited significantly lower IgE avidity indices compared to CU+ individuals (mean AI: 79.9% vs. 88.5%), indicating a less mature IgE response during acute infection. Conversely, IgG4 and IgG avidity were elevated in GAA relative to CU+, reflecting an active but transient immune response. IgA antibodies were detected in both groups, although avidity differences lacked discriminatory capacity. No sex- or age-related differences in antibody avidity were observed. Longitudinal follow-up of GAA patients demonstrated an increase in IgE avidity over time. Conclusions: Quantitative assessment of antibody avidity, particularly for IgE and IgG4, enhances understanding of A. simplex immunopathogenesis and serves as a valuable biomarker for distinguishing acute from chronic clinical presentations. These findings support the use of avidity indices in the diagnosis, staging, and clinical management of anisakiasis. Full article

Advanced glycation end-products (AGEs) are a variety of endogenous and exogenous substances that play an important role in inflammation, allergies, and autoimmune diseases. AGEs’ pathogenicity, alongside advanced oxidation protein products (AOPPs) and other ligands, lies in their ability to bind the receptor for advanced glycation end-products (RAGE) and trigger pro-inflammatory signaling pathways and cytokine release. The literature reports numerous studies on the role of the AGE-RAGE axis in various allergic conditions, including bronchial asthma, atopic dermatitis, food allergies, and autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, or Hashimoto’s thyroiditis, where the significant role of the AGE–RAGE axis in the immunopathogenesis of both allergic and autoimmune conditions is largely discussed and demonstrated. They suggest promising opportunities for the development of new diagnostic markers and targeted therapeutic strategies. However, further large-scale studies are needed to fully understand this multifaceted pathway and translate these insights into effective clinical interventions. Full article

The Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is characterized by profound immune dysregulation where interleukins play a central role in determining disease severity and response to interventions. This review summarizes the role of interleukins in the immunopathogenesis of COVID-19, with particular emphasis on differences observed across major SARS-CoV-2 variants. Pro-inflammatory interleukins like IL-1β, IL-6, IL-2, IL-17 and IL-18 are critically involved in cytokine storm, hyperinflammation, and acute respiratory distress syndrome, whereas anti-inflammatory cytokines like IL-10 contribute to immune regulation and resolution of inflammation. Elevated levels of IL-1α, IL-1β, IL-4, IL-8, IL-9, IL-16, IL-18 have been documented in the Delta variant as compared with the Omicron variant, with IL-6 being the most frequent interleukin reported to be increased across all SARS-CoV-2 variants relative to the ancestral Wuhan strain. Elevated IL-2, IL-4, IL-6, and IL-10 levels have been associated with Omicron sub-variants. The review encompasses interleukin-based therapeutic strategies, where several IL-1 and IL-6 inhibitors were studied across clinical trials, but only tocilizumab has shown some promise against severe COVID-19. IL-2, IL-6, IL-15 and IL-21 levels were positively correlated with IgG and neutralizing antibody activity after vaccination with longevity of post-vaccination immunity being determined by IL-2 and IL-7. Full article

Growth factors play a significant role in the immunopathogenesis of liver diseases, especially liver cirrhosis and hepatocellular carcinoma (HCC). The somatostatin analog octreotide has been used as treatment in advanced HCC, based on its anti-neoplastic effects in vitro. Therefore, the effect of somatostatin and octreotide was studied on several growth factors in patients with HCC. Nineteen patients with advanced HCC were treated with octreotide and compared with thirty-seven patients with viral cirrhosis (19 decompensated) treated with intravenous somatostatin for severe bleeding from portal gastropathy. Five growth factors, namely Gastrin, Insulin-like growth factor 1 (IGF 1), Hepatocyte growth factor (HGF), Stem cell factor (SCF) and Vascular endothelial growth factor (VEGF) were measured in serum before and after treatment with specific commercially available ELISAs. Seventeen healthy individuals and nineteen patients with chronic viral hepatitis C (CAH) were used as pre-treatment controls. Eighteen patients with advanced Primary Biliary Cholangitis (stage III and IV) before and after Ursodeoxycholic acid (UDCA) treatment were also studied. Pre-treatment levels of Gastrin were significantly increased in HCC, cirrhosis and PBC but not in CAH. Levels were significantly reduced by octreotide or somatostatin but also by UDCA in PBC. By contrast, IGF1 showed a mirror image being significantly reduced in HCC, cirrhosis and PBC, but not in CAH. Post-treatment levels were reduced in all groups, but not in PBC. Levels of HGF were significantly increased in HCC and cirrhosis but not in CAH and PBC. They were further increased in HCC after treatment. SCF increased only in HCC and was reduced after octreotide but not after somatostatin treatment. VEGF was reduced in cirrhosis and CAH but not in PBC. It was not significantly increased in HCC, but it was reduced by octreotide and was increased after UDCA. In this retrospective observational study, somatostatin and its analog octreotide have a significant effect on several growth factors involved in HCC pathogenesis. Full article

Background/Objectives: Acute generalized exanthematous pustulosis (AGEP) is a severe drug-induced cutaneous reaction characterized by the abrupt onset of sterile pustules, fever, neutrophilia, and a T cell-mediated type IVd hypersensitivity response. This narrative review synthesizes current evidence on pharmacological triggers, immunopathogenic mechanisms, diagnostic criteria, and differential diagnosis to provide a clinically oriented framework. Methods: A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, ScienceDirect, and SpringerLink for studies published between 2000 and 2025, complemented by selected clinical reference sources. Studies addressing clinical features, immunological pathways, pharmacovigilance signals, and diagnostic tools for AGEP were included. Synthesis of Evidence: β-lactam antibiotics remain the most frequent triggers, while increasing associations have been reported with hydroxychloroquine, targeted therapies, immune checkpoint inhibitors, psychotropic agents, and vaccines. Immunopathogenesis is driven by IL-36 activation, CXCL8/IL-8–mediated neutrophil recruitment, and IL36RN mutations, explaining overlap with pustular psoriasis. Diagnostic accuracy improves through integration of drug latency, clinical morphology, histopathology, biomarkers, and standardized tools such as the EuroSCAR score. Conclusions: AGEP is a complex pustular reaction induced by diverse drugs and amplified by IL-36-mediated inflammation. Accurate diagnosis requires a multidimensional approach supported by structured algorithms and robust pharmacovigilance to identify evolving drug-associated patterns. Full article

Paraneoplastic neurological syndromes (PNSs) are immune-mediated disorders caused by an antitumor response that cross-reacts with the nervous system, leading to severe and often irreversible neurological disability. Once considered exceedingly rare, PNSs are now increasingly recognized owing to the identification of novel neural autoantibodies, wider use of commercial testing, and the emergence of immune checkpoint inhibitor (ICI)-related neurotoxicity that phenotypically overlaps with classic PNS. In this narrative review, we performed a structured search of PubMed/MEDLINE, Scopus, Web of Science, and Google Scholar, without date restrictions, to summarize contemporary advances in the epidemiology, pathogenesis, diagnosis, and management of PNS. Population-based data show rising incidence, largely reflecting improved ascertainment and expanding indications for ICIs. Pathogenetically, we distinguish T-cell-mediated syndromes associated with intracellular antigens from antibody-mediated disorders targeting neuronal surface proteins, integrating emerging concepts of molecular mimicry, tumor genetics, and HLA-linked susceptibility. The 2021 PNS-Care criteria are also reviewed, which replace earlier “classical/non-classical” definitions with risk-stratified phenotypes and antibodies, and demonstrate superior diagnostic performance while underscoring that “probable” and “definite” PNS should be managed with equal urgency. Newly described antibodies and methodological innovations such as PhIP-Seq, neurofilament light chain, and liquid biopsy are highlighted, which refine tumor search strategies and longitudinal monitoring. Management principles emphasize early tumor control, prompt immunotherapy, and a growing repertoire of targeted agents, alongside specific considerations for ICI-associated neurological syndromes. Remaining challenges include diagnostic delays, limited high-level evidence, and the paucity of validated biomarkers of disease activity. Future work should prioritize prospective, biomarker-driven trials and multidisciplinary pathways to shorten time to diagnosis and improve long-term outcomes in patients with PNS. Full article