Search Results (399)

Multiple sclerosis (MS) and allergic diseases, traditionally considered immunologically opposing entities, may share pathogenic mechanisms rooted in immune dysregulation. While MS is predominantly mediated by Th1 and Th17 responses and allergies by Th2 responses, emerging evidence suggests overlapping immunological pathways, including the involvement of histamine, regulatory T cells, and innate lymphoid cells. This review synthesizes current knowledge on the epidemiological and immunopathological associations between MS and allergies. Epidemiological studies have yielded inconsistent results, with some suggesting a protective role for respiratory and food allergies against MS onset, while others find no significant correlation. Clinical studies indicate that food allergies in adults may be associated with increased MS inflammatory activity, whereas childhood atopy might exert a protective effect. In addition, we review hypersensitivity reactions to disease-modifying treatments for MS, detailing their immunological mechanisms, clinical presentation, and management, including desensitization protocols where applicable. Finally, we explore how treatments for allergic diseases—such as clemastine, allergen immunotherapy, montelukast, and omalizumab—may modulate MS pathophysiology, offering potential therapeutic synergies. Understanding the interplay between allergic and autoimmune processes is critical for optimizing care and developing innovative treatment approaches in MS. Full article

Systemic lupus erythematosus (SLE) is a severe autoimmune disease characterized by autoantibody production and multi-organ involvement. Anifrolumab, a monoclonal antibody targeting the type I interferon (IFN) receptor, has been approved for the treatment of SLE. Our aim was to investigate the long-term effects of inhibited type I IFN signaling on circulating follicular helper T subsets (T_FH), follicular regulatory T cells (T_FR), and B lymphocyte subpopulations, reflecting the ongoing germinal center reactions in SLE patients. Peripheral blood samples were obtained from ten SLE patients before the initiation of anifrolumab treatment, and at months 6 and 12 of the intervention period. Flow cytometry analysis was performed to assess the frequencies of circulating T_FH cell subsets, T_FR cells, and certain B cell subpopulations. Serological parameters, including autoantibody levels and complement components, were determined as part of the routine diagnostic evaluation. We observed a significant and sustained reduction in the percentage of activated circulating T_FH cells. Notably, the frequency of CXCR3⁻CCR6⁺ T_FH17 cells decreased, whereas the proportion of CXCR3⁺CCR6⁻ T_FH1 cells increased significantly. Furthermore, the proportion of the IgD⁻CD27⁻ double-negative B lymphocytes was also significantly reduced. These findings suggest that anifrolumab therapy attenuates T_FH cell activation, which may contribute to its clinical efficacy by modulating germinal center responses in SLE. Full article

Background/Objective: Pulmonary fungal infections are a significant diagnostic challenge, primarily affecting immunocompromised individuals, such as those with HIV, cancer, or organ transplants, and they often lead to substantial morbidity and mortality if untreated. These infections trigger acute inflammatory and immune responses, which may progress to chronic inflammation. This process involves myofibroblast recruitment, the deposition of extracellular matrix, and vascular remodeling, ultimately contributing to pulmonary hypertension. Despite its clinical relevance, pulmonary hypertension secondary to fungal infections remains under-recognized in practice and poorly studied in research. Results/Conclusion: This narrative mini-review explores three key mechanisms underlying vascular remodeling in this context: (1) endothelial injury caused by fungal emboli or autoimmune reactions, (2) direct vascular remodeling during chronic infection driven by inflammation and fibrosis, and (3) distant vascular remodeling post-infection, as seen in granulomatous diseases like paracoccidioidomycosis. Further research and clinical screening for pulmonary hypertension in fungal infections are crucial to improving patient outcomes. Full article

Background and Aims: Ornidazole, a nitroimidazole antibiotic, is widely used for protozoal and anaerobic infections and is generally considered safe. However, ornidazole-induced liver injury (OILI) is an underrecognized yet potentially severe adverse reaction. This multicenter study aims to characterize the clinical features, histopathology, and outcomes of OILI to improve the awareness and management of this rare entity worldwide. Methods: We conducted a retrospective analysis of 101 patients with OILI from eight tertiary centers between 2006 and 2023. Cases were included based on liver enzyme elevations temporally linked to ornidazole and the exclusion of other causes. Causality was assessed using the Roussel Uclaf Causality Assessment Method (RUCAM) score. Clinical data, laboratory parameters, autoantibody profiles, histology, treatments, and outcomes were evaluated. Results: OILI was classified as highly probable in 42.6% of cases (n = 43), probable in 51.5% of cases (n = 52), and possible in 5.9% (n = 6) of cases. The predominant pattern was acute hepatocellular injury (83.2%) (n = 84). Autoimmune-like hepatitis occurred in 5% of cases (n = 5), with ANA positivity in 16.8% of cases (n = 17). Corticosteroids were used in 24.8% of cases (n = 25) and were associated with higher ANA positivity and a 20% (n = 5) relapse rate post-discontinuation. Recovery was achieved in 87.7% of cases (n = 88), while 7.9% of cases (n = 8) required liver transplantation and 4% (n = 4) died. Conclusions: Ornidazole can cause serious idiosyncratic liver injury, including autoimmune phenotypes, and should be considered in the differential diagnosis of acute hepatitis. Given the notable risk of liver failure and death, early recognition, drug discontinuation, and close monitoring are essential. In select cases, corticosteroids and plasmapheresis may be beneficial, though the evidence remains limited. Full article

Background/Objectives: Immature platelet fraction (IPF) and reticulated platelets (RPs) are biomarkers reflecting the youngest and most metabolically active platelets in circulation. RPs, a subset of immature platelets, contain residual RNA and have been associated with increased thrombotic potential. Elevated IPF levels indicate enhanced platelet production, commonly observed during elevated platelet turnover, such as in autoimmune reactions, consumption, and thrombotic events. This systematic review aims to evaluate the potential role of IPF and RPs in the context of cerebrovascular events, specifically ischemic and hemorrhagic stroke, as well as transient ischemic attacks (TIAs), and to assess their clinical utility in stroke monitoring and management. Methods: A comprehensive literature search was conducted in PubMed, Scopus, Cochrane Library, and Web of Science for studies published between 2000 and 2024, which focused on IPF and RPs in human subjects with cerebrovascular events. Results: Six studies met the inclusion criteria. Findings suggest that elevated levels of IPF and RP are associated with the acute and chronic phases of ischemic stroke and TIA and may reflect increased platelet turnover and thrombotic activity. Some evidence supports their role in predicting stroke severity, recurrence, and underlying etiology, although results are not yet consistent across all studies. Conclusions: IPF and RPs are emerging biomarkers with potential applications in acute ischemic stroke and risk stratification. While current evidence is promising, further research is needed to standardize measurement techniques and validate their routine use in clinical practice. Full article

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disorder that predominantly affects synovial joints, leading to inflammation, pain, and progressive joint damage. Despite therapeutic advancements, the molecular basis of established RA remains poorly defined. Methods: In this study, we conducted an untargeted plasma proteomic analysis using two-dimensional differential gel electrophoresis (2D-DIGE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) in samples from RA patients and healthy controls in the discovery phase. Results: Significantly (ANOVA, p ≤ 0.05, fold change > 1.5) differentially abundant proteins (DAPs) were identified. Notably, upregulated proteins included mitochondrial dicarboxylate carrier, hemopexin, and 28S ribosomal protein S18c, while CCDC124, osteocalcin, apolipoproteins A-I and A-IV, and haptoglobin were downregulated. Receiver operating characteristic (ROC) analysis identified CCDC124, osteocalcin, and metallothionein-2 with high diagnostic potential (AUC = 0.98). Proteins with the highest selected frequency were quantitatively verified by multiple reaction monitoring (MRM) analysis in the validation cohort. Bioinformatic analysis using Ingenuity Pathway Analysis (IPA) revealed the underlying molecular pathways and key interaction networks involved STAT1, TNF, and CD40. These central nodes were associated with immune regulation, cell-to-cell signaling, and hematological system development. Conclusions: Our combined proteomic and bioinformatic approaches underscore the involvement of dysregulated immune pathways in RA pathogenesis and highlight potential diagnostic biomarkers. The utility of these markers needs to be evaluated in further studies and in a larger cohort of patients. Full article

Psoriasiform dermatitis refers to a spectrum of inflammatory skin disorders that resemble psoriasis both clinically and histologically. These conditions can occur idiopathically or as paradoxical reactions to biologic or targeted therapies, particularly in patients with atopic or autoimmune backgrounds. Histologic features often include acanthosis, parakeratosis, and lymphocytic infiltrates, but without the full molecular signature of classical psoriasis. This review provides an overview of psoriasiform dermatitis with a focus on its clinical presentation, differential diagnosis, and the immune pathways involved. Drug-induced forms, especially those triggered by anti-TNF agents, IL-4/IL-13 blockers, and JAK inhibitors, are highlighted due to their growing clinical relevance. We also summarize the main topical and systemic treatments, including corticosteroids, calcineurin inhibitors, PDE4 inhibitors, and JAK-STAT- or IL-23-targeted therapies. A better understanding of psoriasiform dermatitis is crucial to improve diagnosis and to guide treatment, especially in complex or refractory cases. Full article

IgG antibodies, particularly those of the IgG4 subclass, have generated significant debate regarding their role in immune tolerance versus food intolerance. This article comprehensively reviews the literature on the subject, exploring evidence from healthy individuals and patient populations with varied clinical conditions. On one hand, IgG—especially IgG4—is frequently detected in individuals without adverse food reactions and may represent a normal adaptive immune response to constant dietary antigen exposure, contributing to the development of regulatory T-cell–mediated tolerance. On the other hand, several studies have linked elevated food-specific IgG levels with conditions characterized by increased intestinal permeability and inflammation, including eosinophilic esophagitis, irritable bowel syndrome, inflammatory bowel disease, and autoimmune disorders. The review discusses multiple investigations where IgG-guided elimination diets have yielded symptomatic improvements, suggesting a potential benefit for targeted dietary interventions. However, these findings are tempered by the observation that IgG antibodies are commonly present in asymptomatic individuals, thereby questioning their specificity as markers of adverse food reactions. Current diagnostic guidelines from leading allergy and immunology organizations discourage routine IgG testing for food allergies and intolerances, highlighting that these antibodies might instead indicate exposure or underlying inflammation rather than an actual pathogenic mechanism. There is a need for well-controlled, large-scale studies to clearly define the clinical relevance of food-specific IgG responses. Until more substantial evidence is provided, clinicians are advised to interpret the IgG results cautiously and to consider them within the broader context of each patient’s clinical presentation before recommending restrictive dietary changes. Full article

Aim of the study: Idiopathic inflammatory myopathies (IIM) are autoimmune diseases with a low prevalence and incidence worldwide. The levels of IFN-γ production by T-lymphocytes are related to disease activity. IFN-γ +874 T/A (rs2430561) has been shown to alter the serum levels of IFN-γ in different pathologies. The aim of this work is to explore the role of IFN-γ +874 T/A polymorphism in IIM. Methods: Using a specific sequence primer-polymerase chain reaction (SSP-PCR), the genotype was defined for normal healthy controls (HC) and patients with IIM. Markers of muscle damage, clinical features and treatment were collected from chart at the time of diagnosis and at recruitment point. All the data were analyzed by demographic characteristics, genotype, type of IIM, treatment, clinical features, and enzymatic levels. Results: No association was found comparing the genotypes or alleles of the IIM patients vs. HC. On the other hand, the TT genotype, previously described as a high producer of INF γ, showed higher levels of CPK at diagnosis in IIM patients, whereas females at diagnosis and males in remission presented higher levels. Conclusions: Even with a limited number of patients due to the rarity of this disease, no association was found between the disease development. Further, the TT genotype promoted muscle damage due to CPK elevation in the sera compared to the TA/AA genotype in patients with IIM. This could be genetic evidence of the impact of IFN-γ in the disease activity of IIM patients. A larger cohort is needed to confirm these results. Full article

Human T-lymphotropic virus 1 (HTLV-1) infection has been associated with inflammatory, autoimmune, and lymphoproliferative diseases with a wide spectrum of clinical manifestations. Among patients with inflammatory rheumatological disease manifestations, cases of rheumatoid arthritis, Sjögren’s syndrome, polymyositis, and fibromyalgia, among others, have been reported. Another common feature of rheumatological diseases is the presence of joint manifestations, such as arthralgia and arthritis. In the present study, we sought to determine the laboratory profile and clinical rheumatological manifestations of people living with HTLV-1/2 residing in a metropolitan area in the Brazilian Amazon. A total of 957 individuals were screened for HTLV-1/2 infection by enzyme-linked immunosorbent assay (ELISA), and samples from seropositive individuals were subjected to infection confirmation by Western blotting or quantitative polymerase chain reaction (qPCR). Individuals with confirmed HTLV-1 and HTLV-2 infection were clinically evaluated for signs and symptoms of rheumatological diseases. Of the 957 individuals tested, 69 were positive for HTLV-1/2 infection, with 56 confirmed cases of HTLV-1 infection (5.9%), 12 of HTLV-2 infection (1.2%), and 1 classified as undetermined (0.1%). After clinical screening, 15 infected individuals with complaints suggestive of rheumatological disease were selected for evaluation by a rheumatologist (11 with HTLV-1 infection (1.1%) and 4 with HTLV-2 infection (0.4%)). The predominant pain pattern was symmetrical polyarthralgia, with large joints predominantly being affected. The diseases diagnosed were psoriatic arthritis, osteoarthritis, fibromyalgia, and regional pain syndromes. Antinuclear antibody (ANA) positivity was observed in two patients. Our findings confirm that HTLV-1 infection is associated with rheumatological disease manifestations and highlight the novel finding of cases of HTLV-2 infection in patients with rheumatoid arthritis symptoms. Full article

Background: Narcolepsy type 1 (NT1) is a rare neurological sleep disorder characterized by excessive daytime sleepiness and cataplexy. NT1 is thought to be caused by the loss of hypocretin-producing neurons in the hypothalamus due to autoimmunity. Since cerebrospinal fluid hypocretin testing is invasive and not always feasible in clinical practice, there is a critical need for less invasive biomarkers to improve diagnostic accuracy and accessibility. Very few studies have explored serum-based biomolecules that could serve as biomarkers for NT1. Methods: This study examines the differential abundance of serum metabolites in patients with NT1 using an LC-MS/MS-based comprehensive metabolomics approach. Results: An untargeted analysis identified a total of 1491 metabolites, 453 of which were differentially abundant compared to the control cohort. Ingenuity pathway analysis revealed that key pathways, such as the inflammatory response (p-value of 0.01, activation z-score of 0.5), generation and synthesis of reactive oxygen species (p-value of 0.0008, z-score of 1.3), and neuronal cell death (p-value of 0.04, z-score of 0.4), are predicted to be activated in NT1. A targeted analysis using parallel reaction monitoring validated 49 metabolites, including important downregulated metabolites such as uridine (fold change (FC) of 0.004), epinephrine (FC of 0.05), colchicine (FC of 0.2), corticosterone (FC of 0.3), and arginine (FC of 0.6), as well as upregulated metabolites such as p-cresol sulfate (FC of 2601.7), taurine (FC of 1315.4), inosine (FC of 429.7), and malic acid (FC of 7.9). Conclusions: Understanding the pathways identified in this study and further investigating the differentially abundant metabolites associated with them may pave the way for gaining insight into disease pathogenesis and developing novel therapeutic interventions. Full article

Understanding the mechanisms of immune activation and deactivation is paramount. A host must initiate effective immunity against pathogenic infections while avoiding triggering immunity against self-antigens, which can lead to detrimental autoimmune disorders. Host immunological pathways can be categorized as Immunoglobulin (Ig)G-dominant eradicable immune reactions and IgA-dominant tolerable immune reactions. Eradicable immune reactions include Th1, Th2, Th22, and Thαβ immune responses against four different types of pathogens. Tolerable immune reactions include Th1-like, Th9, Th17, and Th3 immune responses against four different types of pathogens. Here, we try to determine the mechanisms of activation and deactivation of host immune reactions. The spleen and liver play contrasting roles in mediating immune responses: the spleen is primarily involved in immune activation, whereas the liver is responsible for immune deactivation. Similarly, the sympathetic and parasympathetic nervous systems have opposing functions in immune modulation, with the sympathetic system promoting pro-inflammatory responses and the parasympathetic system facilitating anti-inflammatory processes. Furthermore, adrenocorticotropic hormone (ACTH) and glucocorticosteroids exhibit contrasting effects on immune regulation: ACTH is involved in activating adaptive immunity while inhibiting innate immunity, whereas glucocorticosteroids activate natural IgM antibody associated with innate immunity while inhibiting adaptive immunity. Heat shock proteins, particularly molecular chaperones induced by fever, play pivotal roles in immune activation. Conversely, IgD B cells and gamma/delta T cells contribute to immune deactivation through mechanisms such as clonal anergy. Understanding these mechanisms provides insights into immunological pathways, aiding in the better management of infectious diseases and autoimmune disorders. Full article

It is now known that diet or food is one of the environmental factors that can induce or contribute to autoimmunity. In a healthy person with a normal functioning immune system, food substances encounter no resistance and are allowed passage through the immune barriers without triggering immune reactivity. However, clinicians are becoming increasingly aware that modern food-processing methods can increase or decrease the immune reactivity of foods, including allergic reactions. Immune reactions to undigested food antigens could result in the production of IgE antibodies, which are involved in immediate immune reactivity, and in IgG and IgA antibodies, which are involved in delayed immune reactivity. Currently, measurements of these antibodies are generally only performed against antigens derived from raw foods. However, testing for food reactivity based only on raw food consumption is inaccurate because people eat both raw and cooked foods. Even home-cooked foods undergo different kinds of preparation or processing. Food processing can change the structure of raw food materials into secondary, tertiary, and quaternary structures that can have different reactive properties. This can affect the body’s normal oral tolerance of food, causing the immune system to mistakenly identify food as a harmful foreign substance and react to it immunologically, leading to food immune reactivity. This abnormal reaction to food molecules can lead to the production of antibodies against not just target food antigens but also the body’s own tissues, which can have significant implications in autoimmunity induction due to cross-reactivity and the other mechanisms discussed here. We hope that this present review will stimulate further research on the role of modified food antigens in the induction of autoimmunity based on some or all of the key points discussed in this review. Full article

Introduction: About one in four people show an immunological reaction to an infection with Mycobacterium tuberculosis, which can remain latent or lead to active forms of the disease. Psoriasis is a chronic, immune-mediated skin disease that can be associated with numerous comorbidities. Biologic therapies have revolutionized psoriasis treatment but carry the risk of reactivating latent tuberculosis infection. However, the link between tuberculosis as a triggering factor for the onset of psoriasis remains unknown. Clinical Case: We present the case of a patient initially diagnosed with secondary pulmonary tuberculosis, who, two months after the diagnosis, showed a remarkable clinical evolution by developing lesions consistent with vulgar psoriasis, necessitating a multidisciplinary treatment approach. Discussions: This unique case highlights the shared immune mechanism of these diseases, particularly involving TNF-α, IL-17, and CD4+ T cells. Conclusions: The coexistence of these conditions raises critical questions about the interplay between infectious and autoimmune diseases and the impact of genetic susceptibility. Full article

Background: Celiac disease (CD) is a type of systemic autoimmune condition triggered by gluten consumption among genetically predisposed individuals. Aim: To assess the knowledge, awareness, and practices pertaining to CD and associated conditions among dietitians in Jordan. Method: A cross-sectional web-based survey was carried out between April and October 2023. The survey was an internet-based questionnaire with closed-ended questions. Results: The majority of dietitians answered correctly that CD is caused due to an immunological reaction to gluten, gliadin, and protamine (91.7%); it is an autoimmune disease (71.2%); and the risk of developing an autoimmune disease is higher among CD patients (78.8). The majority of respondents (93.6%) correctly identified that a strict gluten-free diet is the treatment approach for CD patients. However, only (18.9%) of dietitians correctly identified the FDA guidelines for “Gluten Free” food labeling. Approximately 53.4% of respondents identified immunoglobulin (IgA) antibody testing as the most reliable way to diagnose patients with CD. Conclusions: The dietitians have a good understanding of CD topics. The development of credentials in CD would ensure that dietitians practicing in CD are skilled. Full article