Search Results (971)

Allergic contact dermatitis (ACD) is a common inflammatory skin disease induced by exposure of the skin to contact allergens. Classically, ACD is defined as a delayed-type (type IV) hypersensitivity reaction mediated by allergen-specific T cells, with symptoms peaking 48–72 h after exposure to the contact allergen. This delayed response to the contact allergen is seen during patch testing, where allergen-naïve, unaffected skin of allergic individuals is exposed to the contact allergen. However, in daily life and in certain occupational settings, allergic individuals often experience rapid flare-ups/exacerbations with intensely itching erythema, oedema, and often vesicles within hours after re-exposure to the specific contact allergen. These rapid flare-ups only develop at skin sites previously exposed to the contact allergen. Thus, it is important to distinguish between the rapid-onset reaction typically experienced by the allergic individual and the delayed-type reaction typically seen after patch testing. This review summarizes current insights into the immunopathology of rapid- versus delayed-type ACD reactions and outlines potential therapeutic opportunities, as well as their current limitations, against rapid-onset ACD, including modulation of cytokine signaling, T cell survival, checkpoint pathways, and redox balance. Full article

Objectives: To assess the association between serum concentrations of adalimumab (ADL) and etanercept (ETN) and the occurrence of a flare in rheumatoid arthritis (RA) patients who are tapering methotrexate (MTX) or their TNF inhibitor. In addition, we explored the impact of tapering MTX on immunogenicity in patients with longstanding ADL use. Methods: ADL and ETN serum concentrations and anti-drug antibodies (ADAs) quantified with a drug-tolerant assay were determined in all RA patients who participated in the TARA trial. Within the TARA trial, two tapering strategies were compared, namely gradually tapering MTX followed by tapering a TNF-inhibitor (ADL or ETN) or vice versa. Results: In the current analysis, 111 RA patients who strictly followed the tapering strategy and had >3 blood samples were included, of them 41% tapered ADL and 59% tapered ETN. Both ADL and ETN concentrations decreased during tapering and stopping, but ADL was longer detectable after cessation compared to ETN. If MTX was tapered first, more ADAs against ADL were detectable in the serum, but it did not affect the serum concentrations. Conclusions: Our data showed that the majority of flares occur when the median serum concentration of ADL and ETN falls below 1 mg/L. If MTX is tapered first, there is a notable increase in the detection of ADAs, but this does not impact the median ADL serum concentration. Full article

Neutrophils are the most abundant immune cells in the human body. Neutrophil extracellular traps (NETs) have recently garnered significant attention as a novel, non-traditional mechanism for combating pathogenic microorganisms. Recent studies have shown that NETs play a crucial role in antiviral immunity, providing new perspectives on how neutrophils defend against viral invasion. Viruses not only induce NET formation through various mechanisms but have also developed multiple escape strategies targeting NETs. It is worth noting that NETs are a double-edged sword for the host: while they possess antiviral effects that inhibit viral spread and replication, their constituent components may also exacerbate tissue damage and play important pathological roles in the progression of certain viral infections. Therefore, a thorough understanding of the regulatory mechanisms and dynamic balance of NETs in viral infections is of critical importance. Additionally, since the components of NETs may vary depending on the stimulus, NET-related markers have the potential to serve as biomarkers for the severity and prognosis of viral diseases. This article provides a systematic review of the induction mechanisms, antiviral effects, viral escape strategies, and virus-induced NET-related immunopathological damage in viral infections, offering new insights for antiviral immunotherapy. Full article

Various therapeutic approaches have been explored to speed up wound healing, with angiogenesis being a crucial factor in this process and skin repair. This study shows that a polysaccharide extracted from the red alga Osmundea pinnatifida (PSOP) can promote angiogenesis and accelerate healing. The structural properties of PSOP were investigated using various techniques, including scanning electron microscopy, X-ray diffraction, Fourier–transform infrared spectroscopy, ultraviolet–-visible spectroscopy, and high-performance liquid chromatography coupled with a refractive index detector. Additionally, the in vitro antioxidant activity of PSOP was evaluated using the reducing power assay, total antioxidant capacity measurement, and DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging tests. The PSOP extract exhibited significant pro-angiogenic effects in the avian chorioallantoic membrane model. Furthermore, the efficacy of PSOP-based hydrogels for wound healing was assessed in vivo using an excision wound model in Wistar rats. The results indicated accelerated wound healing, increased collagen deposition, and enhanced tissue regeneration. Computational studies suggest that the observed wound healing and pro-angiogenic effects may be attributed to the affinity of the PSOP units for cyclooxygenase-2 and vascular endothelial growth factor. These findings support the potential use of PSOP as a bioactive agent in wound care. Full article

Antinuclear antibodies, especially anti-DNA antibodies, are known to be a hallmark of systemic lupus erythematosus (SLE) and represent a diverse pool of autoantibodies with different origins, antigenic properties, and physicochemical features. Antibodies with catalytic properties have been found among the antibody repertoire in SLE, but the specific features and clinical associations of such antibodies have not been sufficiently studied. This study showed that chromatographically purified IgG from the serum of SLE patients effectively hydrolyzed DNA and DNA-associated proteins such as histones and high-mobility group box 1 (HMGB1) compared to healthy individuals. Remarkably, the level of hydrolysis of DNA and DNA-associated proteins was closely correlated. At the same time, these antibodies did not hydrolyze the control protein, tumor necrosis factor-α (TNFα), which does not possess DNA-binding properties. IgG DNase activity levels varied significantly, so patients were divided into high- and low-activity subgroups using the DBSCAN algorithm, with the difference between median values being greater than 49 times. The subgroup with high IgG DNase activity was characterized by an increase in anti-DNA antibodies (p < 0.04) than the subgroup with low activity, which had a shorter duration of the disease (p = 0.03) and was more often characterized by a subacute rather than a non-chronic course of the disease (p = 0.048). High catalase-like activity of IgG was also detected in SLE. Thus, the antibody pool in SLE contains not only high-affinity antinuclear autoantibodies but also catalytic antibodies capable of hydrolyzing DNA and DNA-associated proteins. These findings expand our understanding of the heterogeneity of the repertoire of catalytic autoantibodies among SLE patients. Full article

Myelin oligodendrocyte glycoprotein antibody–associated disease (MOGAD) is an inflammatory demyelinating disorder of the central nervous system characterised by heterogeneous clinical and radiological presentations. Accurate interpretation of serum anti–myelin oligodendrocyte glycoprotein (anti-MOG) antibody titres is critical to improve diagnostic precision and prognostic assessment. This single-centre retrospective study evaluated 19 patients diagnosed with MOGAD in 2023, all of whom were seropositive for anti-MOG IgG, as confirmed by live cell-based assays (CBAs) using full-length human MOG and IgG1-specific secondary antibodies. Antibody quantification combined a ratiometric semi-quantitative fluorescence index with classical endpoint dilution titres, enabling classification into low, medium, and high titre groups. Stratification revealed titre-dependent phenotypic heterogeneity: high-titre patients were older at onset and predominantly presented with optic neuritis, often bilateral, and encephalic involvement, whereas low-titre patients more frequently exhibited spinal cord syndromes, cerebellar or brainstem symptoms, and a higher prevalence of cerebrospinal fluid-restricted oligoclonal bands. Semi-quantitative fluorescence ratios correlated consistently with endpoint titres, and exponential decay analysis demonstrated slower signal loss in high-titre sera, confirming assay reliability. No significant association emerged between titre level and monophasic versus relapsing disease course. Anti-MOG antibody titres could serve not only as a diagnostic biomarker but also to capture clinically relevant immunopathological diversity, supporting a titre-stratified approach to diagnosis and early prognostication. Incorporating semi-quantitative metrics alongside clinical and imaging features may refine the diagnostic algorithm and prevent misclassification of atypical presentations. Full article

Therapeutic plasma exchange (TPE) is increasingly recognized as a critical escalation therapy for managing acute multiple sclerosis (MS) relapses refractory to high-dose corticosteroids. Neuropathological and clinical evidence implicate humoral immune mechanisms, particularly autoantibodies, immune complexes, and complement activation, as key pathogenic drivers in a subset of MS attacks, notably those consistent with immunopathological pattern II. By removing these circulating immune effectors, TPE provides a rational strategy to dampen inflammation and promote neurological recovery. This review integrates current mechanistic insights with clinical efficacy data and practical implementation strategies for TPE in corticosteroid-refractory MS. Evidence from randomized controlled trials and observational cohorts demonstrates moderate-to-marked functional improvement in 40–60% of patients, with the greatest benefit observed when therapy is initiated within 14 days of symptom onset and cases demonstrating active inflammatory lesions on MRI. Predictors of a favorable response include younger age, short disease duration, severe syndromes involving optic nerve, brainstem, or spinal cord, and CSF markers of intrathecal B-cell activity. Although TPE is generally well tolerated in experienced centers, its broader adoption of TPE is limited by variability in access, institutional protocols, and provider familiarity. Standardization of treatment algorithms, validation of predictive biomarkers, and incorporation into streamlined clinical pathways are critical to maximizing its clinical impact. Future priorities include comparative trials against alternative escalation therapies, biomarker-guided patients’ selection, and comprehensive health-economic evaluations. Taken together, current evidence and recommendations from major neurology and apheresis societies support TPE as a valuable therapeutic modality capable of significantly improving relapse outcomes in appropriately selected MS patients. Full article

Background/Objectives: Some lung transplant (LungTx) recipients do not achieve the expected lung function within the first year, a condition known as baseline lung allograft dysfunction (BLAD). Our objective was to analyze the risk factors associated with BLAD, focusing on the variables associated with a higher risk of developing a more intense alloimmune response. Methods: We carried out a prospective study including 88 LungTx recipients. BLAD was defined as failure to reach 80% of the predicted value for forced expiratory volume in one second (FEV1) and/or forced vital capacity (FVC) on two tests conducted at least three weeks apart. Tacrolimus time in therapeutic range (TTR) and mycophenolic acid area under the curve (MPA AUC_0–12h) were measured at the third month. Donor–recipient compatibility was assessed using HLA eplet mismatch analysis, performed via HLA Matchmaker 3.1. Results: BLAD patients showed greater eplet mismatch burden (67, IQR 20 vs. 55, IQR 22, p = 0.018) and had been exposed to a lower TTR (26.6%, IQR 14.0% vs. 39.6%, IQR 24.3%, p = 0.039) and less frequently to an adequate third-month MPA AUC_0–12 > 30 mg × h/L (57.1% vs. 89.2%, p = 0.020). DR/DQ eplet mismatches (β = −0.348, p = 0.002) and third-month MPA AUC_0–12 (β = 0.285, p = 0.009) were independently associated with six-month predicted FEV1%. Conclusions: Among other variables, BLAD and initial lung graft function are associated with greater eplet discordance and lower immunosuppressive drug exposure, suggesting a potential role of underlying alloimmune responses in their pathogenesis. Full article

Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) has emerged as a distinct autoimmune demyelinating disorder, characterised by clinical, radiological, and immunopathological features that differentiate it from Multiple Sclerosis (MS) and AQP4+ neuromyelitis optica spectrum disorder (AQP4+NMOSD). This review provides a comprehensive synthesis of the evolving landscape of MOGAD, from its immunopathogenesis and diagnostic criteria to treatment strategies and global epidemiological insights. We explore the role of MOG-IgG antibodies in disease mechanisms, the utility of emerging biomarkers, and the prognostic value of tools like clinical scores or longitudinal MOG-IgG assessment. Special attention is given to regional disparities, with a focus on Latin America, highlighting diagnostic delays, access inequities, and unique clinical phenotypes. We also examine the limitations of current evidence, including gaps in long-term longitudinal follow-up and variability in diagnostic testing. Finally, we discuss global collaborative efforts and clinical trials that are shaping the future of personalised care in MOGAD. As the field advances, integrating biomarker-driven monitoring, equitable access to therapies, and regionally adapted guidelines will be essential to improving outcomes for patients worldwide. Full article

The mismatch repair system is critical for correcting base–base mismatches and insertion-deletion loops during DNA replication. Deficiencies in MMR (due to mutations in MLH1, MSH2, MSH6, or PMS2) lead to microsatellite instability and contribute to the development of various cancers, such as Lynch syndrome-related colorectal cancer and sporadic tumors. This review will delve into the molecular basis of MMR deficiency. Additionally, the review will cover diagnostic approaches for detecting MSI and MMR deficiency, including next-generation sequencing and PCR-based methods. The implications for treatment will be discussed, emphasizing immune checkpoint inhibitors (e.g., pembrolizumab) that target tumors with high mutational burdens due to MMR deficiency, as well as novel therapeutic approaches like synthetic lethality exploiting DNA repair vulnerabilities. Full article

Jellyfish stings represent a significant global marine hazard, causing injuries from localized skin damage to fatal systemic complications. While skin reactions are the most common symptom, heart toxicity (cardiotoxicity) is the primary cause of death. A growing body of evidence shows that the immune system’s response worsens this venom-induced heart damage. However, current research remains disproportionately focused on cutaneous inflammatory responses, leaving systemic immunopathological processes—especially those potentiating cardiotoxicity—poorly understood. Moreover, few jellyfish toxins (like those from the Chironex fleckeri) have been thoroughly studied, and the molecular mechanisms of heart injury remain largely unknown. This review introduces a novel pathophysiological classification of jellyfish envenomation into three distinct categories—immunotoxicity-dominant, cardiotoxicity-dominant, and dual-mechanism synergistic—based on clinical and mechanistic profiles. By synthesizing current knowledge on venom components and their multi-system interaction, we aim to identify actionable therapeutic targets and propose mechanism-driven treatment strategies. This refined classification offers a foundation for future clinical decision-making and the development of targeted therapies, potentially improving patient outcomes through more personalized envenomation management. Full article

Inducible forms of chronic urticaria are characterized by an early age of onset and a long duration of disease. In addition, cold and cholinergic urticaria have a risk of developing systemic, sometimes life-threatening, reactions. Determining the pathogenetic mechanisms and laboratory and clinical predictors of their development is an open question in the understanding of these diseases. This literature review demonstrates the current known facts that allow the identification of patients with cold and cholinergic urticaria in high-risk groups of anaphylaxis development and, therefore, the possibility to prevent emergency situations and to manage them in time. For cold and cholinergic urticaria, observations of Kounis syndrome–acute coronary syndrome (myocardial infarction or unstable angina) have been described. A series of trials, including the large international multicenter COLD-CE study of anaphylaxis in cold urticaria, have identified early age of urticaria onset, severe clinical symptoms, shortening of the critical temperature threshold, comorbid bronchial asthma, concomitant angioedema, and pruritus of the earlobes as warning signs. No such large-scale studies have been conducted for cholinergic urticaria. Among the few high-risk factors for systemic reactions in cholinergic urticaria described in the literature is the occurrence of angioedema. Thus, it is possible to identify some patients in the high-risk group already at the stage of initial anamnesis collection, and additional data can be collected during the examination. Laboratory biomarkers, clinical predictors, understanding the mechanisms of anaphylaxis by physical triggers or their consequences, and optimal options for pathogenetic therapy are still unresolved issues that require further research. The aim of this review is to provide a content analysis of current knowledge about chronic inducible urticarias in order to increase clinicians’ awareness and, consequently, reduce the risk of urgent conditions associated with them. Full article

The early secreted antigenic target of 6 kDa (ESAT-6), a main effector molecule of the ESX-1 secretion system, is identified as a virulence determinant and immunoregulatory protein of Mycobacterium tuberculosis (Mtb), affecting the interaction between host immune cells and pathogens. ESAT-6 facilitates the survival of mycobacteria and their cell-to-cell spreading through membrane-permeabilizing activity and the regulation of host immune cell functions. In this review, we first summarize the recent knowledge of the roles of ESAT-6 in the survival of bacteria, phagosomal escape, and pathogenicity during Mtb infection. Then, we focused on its complex immunomodulatory effects on different immune cells, such as macrophages, dendritic cells, neutrophils, and T cells, accentuating its capability to either facilitate or inhibit immune responses through different signaling pathways. While our review has summarized its main roles in immunopathology in the context of tuberculosis, we additionally search for emerging evidence indicating that ESAT-6 has anti-inflammatory and immunosuppressive properties. Particularly, we discuss recent preclinical studies showing its capability to suppress transplant rejection and alloimmunity, probably via the induction of regulatory T cells. Nevertheless, the potential clinical use of ESAT-6 remains uncertain and needs further verification by comprehensive preclinical and clinical studies. Thus, we propose that ESAT-6 may be exploited to ameliorate immunopathology in TB infection and to suppress immune-mediated inflammation or transplant rejection as well. Full article

The reactivation of BK polyomavirus (BKPyV) during severe immunosuppression plays a crucial role in two significant syndromes observed in transplant recipients: BK polyomavirus-associated nephropathy (BKPyVAN) in kidney transplant patients and BK polyomavirus-associated hemorrhagic cystitis (BKPyV-HC) in hematopoietic cell transplant (HCT) recipients. This review aims to summarize the current understanding and lingering ambiguity by looking at three primary questions: (1) In cases with BKPyV-related illnesses in transplant patients, which diagnostic methods have the best track record of accuracy and success? (2) Which therapy approaches have the best track records of safety and efficacy in real-world clinical settings? (3) What can immunological research teach us about the development of future tailored treatments? Diagnosis involves the patient’s appearance, ruling out other potential causes, and employing quantitative PCR to identify active viral replication in urine or plasma. BKPyV-HC can vary from self-limited hematuria to potentially fatal bleeding, while BKPyVAN may lead to loss and dysfunction of the allograft. Reducing immunosuppression remains the key aspect of treatment. However, the effectiveness of antivirals (such cidofovir and leflunomide) is not always the same, and supporting measures depend on the syndrome. Researchers are looking into new immunotherapies, such as virus-specific cytotoxic T cells. Due to the intricate viro-immunopathology and lack of defined treatment regimens, future initiatives should focus on prospective studies to establish validated thresholds, enhance management algorithms, and integrate immune surveillance into individualized therapy. Full article

While Moringa oleifera Lam. (MO) extracts are known to have various bioactive properties, including anti-inflammatory properties, the components responsible still remain to be identified. This study explores the protective effects of the MO component, 7-octenoic acid (7OCT) in LPS-stimulated THP-1 macrophage inflammatory responses. The compound significantly downregulated the production of the pro-inflammatory cytokines TNF-α, IL-1β, and IL-6, as well as the expression of inflammation-related genes NFKB1, PTGS2, and NOS2. Additionally, it inhibited the nuclear translocation of NF-κB p65, a key transcription factor of inflammatory signaling cascade. Effects on oxidative stress showed that 7OCT inhibited LPS-induced NADPH oxidase 2 (NOX2) component genes including CYBB, CYBA, NCF1, NCF2, and NFE2L2, along with phosphorylated NOX2 and p47^phox proteins. The compound reduced the expression of TP53, BAX, CASP3, and CASP7, while enhancing BCL2 expression and Bcl-2 protein levels, suggesting an effect on apoptosis. Decreased levels of BAX, caspase-3, and cleaved caspase-3 proteins further confirmed its anti-apoptotic effect. Our findings suggest that 7OCT exhibits strong anti-inflammatory, antioxidant, and anti-apoptotic properties. Full article