RESUMEN
Multiple sclerosis (MS) is an autoimmune disorder where T cells attack neurons in the central nervous system (CNS) leading to demyelination and neurological deficits. A driver of increased MS risk is the soluble form of the interleukin-7 receptor alpha chain gene (sIL7R) produced by alternative splicing of IL7R exon 6. Here, we identified the RNA helicase DDX39B as a potent activator of this exon and consequently a repressor of sIL7R, and we found strong genetic association of DDX39B with MS risk. Indeed, we showed that a genetic variant in the 5' UTR of DDX39B reduces translation of DDX39B mRNAs and increases MS risk. Importantly, this DDX39B variant showed strong genetic and functional epistasis with allelic variants in IL7R exon 6. This study establishes the occurrence of biological epistasis in humans and provides mechanistic insight into the regulation of IL7R exon 6 splicing and its impact on MS risk.
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ARN Helicasas DEAD-box/metabolismo , Epistasis Genética , Subunidad alfa del Receptor de Interleucina-7/genética , Empalme del ARN , ARN Helicasas DEAD-box/genética , Exones , Células HeLa , Humanos , Esclerosis Múltiple/genética , Biosíntesis de Proteínas , ARN Interferente Pequeño/metabolismo , Linfocitos T/inmunologíaRESUMEN
Here we critically discuss data supporting the view that microbial agents (pathogens, pathobionts or commensals alike) play a relevant role in the pathogenesis of multifactorial diseases, but their role is concealed by the rules presiding over T cell antigen recognition and trafficking. These rules make it difficult to associate univocally infectious agents to diseases' pathogenesis using the paradigm developed for canonical infectious diseases. (Cross-)recognition of a variable repertoire of epitopes leads to the possibility that distinct infectious agents can determine the same disease(s). There can be the need for sequential infection/colonization by two or more microorganisms to develop a given disease. Altered spreading of infectious agents can determine an unwanted activation of T cells towards a pro-inflammatory and trafficking phenotype, due to differences in the local microenvironment. Finally, trans-regulation of T cell trafficking allows infectious agents unrelated to the specificity of T cell to modify their homing to target organs, thereby driving flares of disease. The relevant role of microbial agents in largely prevalent diseases provides a conceptual basis for the evaluation of more specific therapeutic approaches, targeted to prevent (vaccine) or cure (antibiotics and/or Biologic Response Modifiers) multifactorial diseases.
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Interacciones Microbiota-Huesped , Interacciones Huésped-Patógeno , Linfocitos TRESUMEN
BACKGROUND: There are two major genetic types of Epstein-Barr Virus (EBV): type 1 (EBV-1) and type 2 (EBV-2). EBV functions by manipulating gene expression in host B cells, using virus-encoded gene regulatory proteins including Epstein-Barr Nuclear Antigen 2 (EBNA2). While type 1 EBNA2 is known to interact with human transcription factors (hTFs) such as RBPJ, EBF1, and SPI1 (PU.1), type 2 EBNA2 shares only ~ 50% amino acid identity with type 1 and thus may have distinct binding partners, human genome binding locations, and functions. RESULTS: In this study, we examined genome-wide EBNA2 binding in EBV-1 and EBV-2 transformed human B cells to identify shared and unique EBNA2 interactions with the human genome, revealing thousands of type-specific EBNA2 ChIP-seq peaks. Computational predictions based on hTF motifs and subsequent ChIP-seq experiments revealed that both type 1 and 2 EBNA2 co-occupy the genome with SPI1 and AP-1 (BATF and JUNB) hTFs. However, type 1 EBNA2 showed preferential co-occupancy with EBF1, and type 2 EBNA2 preferred RBPJ. These differences in hTF co-occupancy revealed possible mechanisms underlying type-specific gene expression of known EBNA2 human target genes: MYC (shared), CXCR7 (type 1 specific), and CD21 (type 2 specific). Both type 1 and 2 EBNA2 binding events were enriched at systemic lupus erythematosus (SLE) and multiple sclerosis (MS) risk loci, while primary biliary cholangitis (PBC) risk loci were specifically enriched for type 2 peaks. CONCLUSIONS: This study reveals extensive type-specific EBNA2 interactions with the human genome, possible differences in EBNA2 interaction partners, and a possible new role for type 2 EBNA2 in autoimmune disorders. Our results highlight the importance of considering EBV type in the control of human gene expression and disease-related investigations.
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Infecciones por Virus de Epstein-Barr , Herpesvirus Humano 4 , Humanos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/metabolismo , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/metabolismo , Genoma Humano , Antígenos Nucleares del Virus de Epstein-Barr/genética , Antígenos Nucleares del Virus de Epstein-Barr/metabolismo , Proteínas Virales/genética , Factores de Transcripción/metabolismoRESUMEN
Fyn, Blk, and Lyn are part of a group of proteins called Src family kinases. They are crucial in controlling cell communication and their response to the growth, changes, and immune system. Blocking these proteins with inhibitors can be a way to treat diseases where these proteins are too active. The primary mode of action of these inhibitors is to inhibit the phosphorylation of Fyn, Blk, and Lyn receptors, which in turn affects how signals pass within the cells. This review shows the structural and functional aspects of Fyn, Blk, and Lyn kinases, highlighting the significance of their dysregulation in diseases such as cancer and autoimmune disorders. The discussion encompasses the design strategies, SAR analysis, and chemical characteristics of effective inhibitors, shedding light on their specificity and potency. Furthermore, it explores the progress of clinical trials of these inhibitors, emphasizing their potential therapeutic applications.
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Proteínas Tirosina Quinasas , Proteínas Proto-Oncogénicas , Proteínas Tirosina Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-fyn/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Familia-src Quinasas , FosforilaciónRESUMEN
PURPOSE: Owing to adverse event following immunization (AEFI) related to autoimmune disorders and coronavirus disease 2019 (COVID-19) vaccines sharing common biological mechanisms, identifying the risk of AEFIs associated with COVID-19 vaccines remains a critical unmet need. We aimed to assess the potential safety signals for 16 AEFIs and explore co-reported adverse events (AEs) and drugs using the global database of the World Health Organization, VigiBase. METHODS: We assessed the occurrence of 16 AEFIs following COVID-19 vaccination through the Standardized MedDRA Queries group "Immune-mediated/Autoimmune Disorders" from MedDRA and performed a disproportionality analysis using reporting odds ratio (ROR) and information component (IC) with 95% confidence intervals (CIs). RESULTS: We identified 25,219 events associated with COVID-19 vaccines in VigiBase. Although rare, we detected four potential safety signals related to autoimmune disorders following COVID-19 vaccination, including ankylosing spondylitis or psoriatic arthritis (ROR 1.86; 95% CI 1.53-2.27), inflammatory bowel disease (ROR 1.77; 95% CI 1.60-1.96), polymyalgia rheumatica (ROR 1.42; 95% CI 1.30-1.55), and thyroiditis (ROR 1.40; 95% CI 1.30-1.50), with positive IC025 values. The top co-reported AEs were musculoskeletal disorders, and immunosuppressants were the most representative co-reported drugs. CONCLUSION: In addressing the imperative to comprehend AEFI related to autoimmune disorders following COVID-19 vaccination, our study identified four potential safety signals. Thus, our research underscores the importance of proactive safety monitoring for the identification of the four AEFIs following COVID-19 vaccination, considering the associated advantages.
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Enfermedades Autoinmunes , COVID-19 , Humanos , Vacunas contra la COVID-19/efectos adversos , Farmacovigilancia , COVID-19/epidemiología , COVID-19/prevención & control , Vacunación/efectos adversos , Enfermedades Autoinmunes/inducido químicamente , Enfermedades Autoinmunes/epidemiología , Sistemas de Registro de Reacción Adversa a MedicamentosRESUMEN
TMEM39A encodes an evolutionarily conserved transmembrane protein and carries single-nucleotide polymorphisms associated with increased risk of major human autoimmune diseases, including multiple sclerosis. The exact cellular function of TMEM39A remains not well understood. Here, we report that TMEM-39, the sole Caenorhabditis elegans (C. elegans) ortholog of TMEM39A, regulates lysosome distribution and accumulation. Elimination of tmem-39 leads to lysosome tubularization and reduced lysosome mobility, as well as accumulation of the lysosome-associated membrane protein LMP-1. In mammalian cells, loss of TMEM39A leads to redistribution of lysosomes from the perinuclear region to cell periphery. Mechanistically, TMEM39A interacts with the dynein intermediate light chain DYNC1I2 to maintain proper lysosome distribution. Deficiency of tmem-39 or the DYNC1I2 homolog in C. elegans impairs mTOR signaling and activates the downstream TFEB-like transcription factor HLH-30. We propose evolutionarily conserved roles of TMEM39 family proteins in regulating lysosome distribution and lysosome-associated signaling, dysfunction of which in humans may underlie aspects of autoimmune diseases.
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Enfermedades Autoinmunes/genética , Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/genética , Secuencia Conservada/genética , Lisosomas/metabolismo , Proteínas de la Membrana/genética , Animales , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/metabolismo , Dineínas/metabolismo , Predisposición Genética a la Enfermedad , Proteínas de la Membrana/química , Proteínas de la Membrana/metabolismo , Mutación/genética , Neuronas/metabolismo , Factores de Riesgo , Transducción de Señal , Tejido Subcutáneo/metabolismo , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
INTRODUCTION: Increasing evidence suggests that autoimmune disorders and their immunomodulating medications may increase the risk of rhinosinusitis compared to rhinitis. GOAL: To investigate the association between autoimmune disorders and rhinosinusitis. METHODS: We performed a case-control study of patients referred to West Virginia University from August 2020 to October 2022 for rhinologic complaints. Rhinosinusitis patients were diagnosed with either chronic rhinosinusitis (CRS) or recurrent acute rhinosinusitis (RARS). These patients were compared to non-rhinosinusitis patients. Patients' characteristics, comorbidities, and type of treatment of autoimmune disorders were reviewed. RESULTS: The sample consisted of 527 rhinosinusitis [184 CRS without nasal polyps (CRSsNP), 263 CRS with nasal polyps (CRSwNP) and 80 RARS patients] patients and 564 non-rhinosinusitis patients. Patients with rhinosinusitis were more likely to be older, males, have asthma, and have current and past smoking history (all with p-value < 0.05). Autoimmune disorders, primary antibody deficiency, and immunomodulator agents were more common in rhinosinusitis patients (16.5 % vs 9.4 %, OR = 1.9, p < 0.001; 5.1 % vs 0.5 %, OR = 10.1, p < 0.001; and 3.8 % vs 1.1 %, OR = 3.7, p = 0.003 respectively). Multivariate logistic regression adjusting for confounders showed that autoimmune disorders were strongly associated with rhinosinusitis [OR = 1.6, 95 % CI = 1.10-2.48], whereas the immunomodulators did not reach statistical significance [OR = 2.4, 95 % CI = 0.87-6.47]. Subgroup analysis showed the autoimmune disorders did not significantly differ between CRS and RARS groups [OR = 1.0, 95 % CI = 0.5-2.1], or between the CRSsNP and CRSwNP groups [OR = 0.9, 95 % CI = 0.5-1.7]. CONCLUSION: Autoimmune disorders are associated with rhinosinusitis, both CRS and RARS, independently of other risk factors.
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Enfermedades Autoinmunes , Pólipos Nasales , Rinosinusitis , Sinusitis , Adulto , Masculino , Humanos , Estudios de Casos y Controles , Pólipos Nasales/complicaciones , Pólipos Nasales/epidemiología , Sinusitis/complicaciones , Sinusitis/epidemiología , Enfermedades Autoinmunes/complicaciones , Enfermedades Autoinmunes/epidemiología , Adyuvantes Inmunológicos , Enfermedad CrónicaRESUMEN
Immune disorders arise from complex genetic and environmental factors, which lead to dysregulation at the cellular and inflammatory levels and cause tissue damage. Recent research highlights the crucial role of reactive antibodies in autoimmune diseases and graft rejection, but their complex determination poses challenges for clinical use. Therefore, our study aimed to ascertain whether the presence of reactive antibodies against membrane antigens in tissues from both animal models and humans could serve as biomarkers in patients with autoimmune disorders. To address this issue, we examined the binding profile of serological antibodies against a diverse panel of cell membranes from the spleen, liver, and kidney tissues of monkeys, rats, and humans. After developing the cell membrane microarrays, human sera were immunologically assayed. The study was first conducted on sera from two groups, healthy subjects and patients with inflammatory and autoimmune disorders, and then optimized for kidney transplant patient sera. A significant increase in antibody reactivity against specific monkey kidney and spleen membranes was observed in the serum of patients with lupus nephritis, while kidney transplant patients showed a significant enhancement against human tissues and human embryonic kidney 293 cells. These results show the potential importance for clinical and basic research purposes of studying the presence of specific IgG against membrane antigens in patients' serum as potential biomarkers of immune disorders. However, it is important to note that these results need to be verified in further studies with a larger sample size to confirm their relevance.
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Nefritis Lúpica , Bazo , Humanos , Ratas , Animales , Antígenos , Hígado , Autoanticuerpos , Riñón , Rechazo de InjertoRESUMEN
Bruton's tyrosine kinase (BTK) inhibitors have revolutionized the landscape for the treatment of hematological malignancies, solid tumors, and, recently, autoimmune disorders. The BTK receptor is expressed in several hematopoietic cells such as macrophages, neutrophils, mast cells, and osteoclasts. Similarly, the BTK receptor is involved in signaling pathways such as chemokine receptor signaling, Toll-like receptor signaling, and Fc receptor signaling. Due to their unique mechanism, these agents provide a diverse utility in a variety of disease states not limited to the field of malignant hematology and are generally well-tolerated.
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Neoplasias Hematológicas , Neoplasias , Humanos , Agammaglobulinemia Tirosina Quinasa , Transducción de Señal , Neoplasias/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéuticoRESUMEN
A few cases of multiple sclerosis (MS) onset after COVID-19 vaccination have been reported, although the evidence is insufficient to establish causality. The aim of this study is to compare cases of newly diagnosed relapsing-remitting MS before and after the outbreak of the COVID-19 pandemic and the impact of COVID-19 vaccination. Potential environmental and genetic predisposing factors were also investigated, as well as clinical patterns. This is a single-centre retrospective cohort study including all patients who presented with relapsing-remitting MS onset between January 2018 and July 2022. Data on COVID-19 vaccination administration, dose, and type were collected. HLA-DRB1 genotyping was performed in three subgroups. A total of 266 patients received a new diagnosis of relapsing-remitting MS in our centre, 143 before the COVID-19 pandemic (until and including March 2020), and 123 during the COVID-19 era (from April 2020). The mean number of new MS onset cases per year was not different before and during the COVID-19 era and neither were baseline patients' characteristics, type of onset, clinical recovery, or radiological patterns. Fourteen (11.4%) patients who subsequently received a new diagnosis of MS had a history of COVID-19 vaccination within one month before symptoms onset. Patients' characteristics, type of onset, clinical recovery, and radiological patterns did not differ from those of patients with non-vaccine-related new diagnoses of MS. The allele frequencies of HLA-DRB1*15 were 17.6% and 22.2% in patients with non-vaccine-related disease onset before and during the COVID-19 era, respectively, while no case of HLA-DRB1*15 was identified among patients with a new diagnosis of MS post-COVID-19 vaccine. In contrast, HLA-DRB1*08+ or HLA-DRB1*10+ MS patients were present only in this subgroup. Although a causal link between COVID-19 vaccination and relapsing-remitting MS cannot be detected, it is interesting to note and speculate about the peculiarities and heterogeneities underlying disease mechanisms of MS, where the interactions of genetics and the environment could be crucial also for the follow-up and the evaluation of therapeutic options.
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Vacunas contra la COVID-19 , COVID-19 , Cadenas HLA-DRB1 , Haplotipos , SARS-CoV-2 , Humanos , Femenino , Masculino , Cadenas HLA-DRB1/genética , Adulto , COVID-19/genética , COVID-19/prevención & control , COVID-19/inmunología , COVID-19/epidemiología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/inmunología , Estudios Retrospectivos , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Persona de Mediana Edad , Vacunación , Esclerosis Múltiple Recurrente-Remitente/genética , Esclerosis Múltiple Recurrente-Remitente/inmunología , Esclerosis Múltiple/genética , Predisposición Genética a la EnfermedadRESUMEN
Some 90 autoimmune disorders have been described in medical literature, affecting most of the tissues within the body. Autoimmune disorders may be difficult to treat, and there is a need to develop novel therapeutic strategies for these disorders. Autoimmune disorders are characterised by mitochondrial dysfunction, oxidative stress, and inflammation; there is therefore a rationale for a role for coenzyme Q10 in the management of these disorders, on the basis of its key role in normal mitochondrial function, as an antioxidant, and as an anti-inflammatory agent. In this article, we have therefore reviewed the potential role of CoQ10, in terms of both deficiency and/or supplementation, in a range of autoimmune disorders.
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Enfermedades Autoinmunes , Ubiquinona , Ubiquinona/análogos & derivados , Ubiquinona/uso terapéutico , Humanos , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/metabolismo , Animales , Estrés Oxidativo/efectos de los fármacos , Antioxidantes/uso terapéutico , Mitocondrias/metabolismoRESUMEN
Iterative advances in understanding of the genetics of type 1 diabetes have identified >70 genetic regions associated with risk of the disease, including strong associations across the HLA class II region that account for >50% of heritability. The increased availability of genetic data combined with the decreased costs of generating these data, have facilitated the development of polygenic scores that aggregate risk variants from associated loci into a single number: either a genetic risk score (GRS) or a polygenic risk score (PRS). PRSs incorporate the risk of many possibly correlated variants from across the genome, even if they do not reach genome-wide significance, whereas GRSs estimate the cumulative contribution of a smaller subset of genetic variants that reach genome-wide significance. Type 1 diabetes GRSs have utility in diabetes classification, aiding discrimination between type 1 diabetes, type 2 diabetes and MODY. Type 1 diabetes GRSs are also being used in newborn screening studies to identify infants at risk of future presentation of the disease. Most early studies of type 1 diabetes genetics have been conducted in European ancestry populations, but, to develop accurate GRSs across diverse ancestries, large case-control cohorts from non-European populations are still needed. The current barriers to GRS implementation within healthcare are mainly related to a lack of guidance and knowledge on integration with other biomarkers and clinical variables. Once these limitations are addressed, there is huge potential for 'test and treat' approaches to be used to tailor care for individuals with type 1 diabetes.
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Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Recién Nacido , Humanos , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/diagnóstico , Predisposición Genética a la Enfermedad/genética , Factores de Riesgo , Biomarcadores , Estudio de Asociación del Genoma CompletoRESUMEN
BACKGROUND: Patients with Sjögren's syndrome, like other patients with autoimmune disorders, display dysregulation in the function of their immune system. Fas and Fas Ligand (FasL) are among the dysregulated proteins. METHODS: We studied Fas and FasL on IL-2Rα+ cells and in serum of patients with Sjögren's syndrome (n = 16) and healthy individuals (n = 16); both from same ethnic and geographical background. We used flow cytometry and enzyme-linked immunosorbent for this purpose. We also measured the expression of Bcl-2 and Bax by reverse transcription quantitative real-time PCR (RT-qPCR) and percentage of apoptotic and dead cells using Annexin V and 7-AAD staining in lymphocytes. RESULTS: FasL was increased in patients' T and B cells while Fas was increased in patients' monocytes, T and B cells. No signs of increased apoptosis were found. sFas and sFasL in patients' serum were increased, although the increase in sFasL was not significant. We suspect an effect of non-steroidal anti-inflammatory therapy on B cells, explaining the decrease of the percentage Fas+ B cells found within our samples. In healthy individuals, there was a noticeable pattern in the expression of FasL which mutually correlated to populations of mononuclear cells; this correlation was absent in the patients with Sjögren's syndrome. CONCLUSIONS: Mononuclear cells expressing IL-2Rα+ had upregulated Fas in Sjögren's syndrome. However, the rate of apoptosis based on Annexin V staining and the Bcl-2/Bax expression was not observed in mononuclear cells. We suspect a functional role of abnormal levels of Fas and FasL which has not been cleared yet.
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Enfermedades Autoinmunes , Síndrome de Sjögren , Humanos , Anexina A5 , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Apoptosis , Receptor fas/metabolismoRESUMEN
Extracellular vesicles (EVs) are a diverse collection of lipid bilayer-membrane-bound particles which are released from cells into the extracellular space and biologic fluids. In multicellular organisms, these vesicles facilitate the exchange of bioactive compounds such as RNA, DNA, proteins, various metabolites, and lipids between the cells. EVs are produced and released by almost all eukaryotic cells including immune cells and can have immunomodulating effects by either stimulation or suppression of their activities. This immune-modulating feature may provide a promising strategy for treating immune-mediated diseases such as cancer, neurodegenerative diseases, autoimmune disorders and graft-versus-host disease. Moreover, immune cell-derived EVs have received attention as potential biomarkers for being used as diagnostic tools and preventive strategies such as for developing vaccines. In this review, we focus on the EVs produced by different immune cell types, their effects on the immune system, and highlight their potential applications for immunotherapy.
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Vesículas Extracelulares , Vesículas Extracelulares/metabolismo , Inmunomodulación , Inmunoterapia , Sistema Inmunológico , Biomarcadores/metabolismoRESUMEN
Metabolic dysfunction-associated fatty liver disease (MAFLD) occurs in a low-grade inflammatory milieu dependent on highly complex networks that span well-beyond the hepatic tissue injury. Dysfunctional systemic metabolism that characterizes the disease, is further induced in response to environmental cues that modify energy and metabolic cellular demands, thereby altering the availability of specific substrates that profoundly regulate, through epigenetic mechanisms, the phenotypic heterogeneity of immune cells and influence hematopoietic stem cell differentiation fate. This immuno-metabolic signaling drives the initiation of downstream effector pathways and results in the decompensation of hepatic homeostasis that precedes pro-fibrotic events. Recent evidence suggests that innate immune cells reside in different tissues in a memory effector state, a phenomenon termed trained immunity, that may be activated by subsequent exogenous (e.g., microbial, dietary) or endogenous (e.g., metabolic, apoptotic) stmuli. This process leads to long-term modifications in the epigenetic landscape that ultimately precondition the cells towards enhanced transcription of inflammatory mediators that accelerates MAFLD development and/or progression. In this mini review we aimed to present current evidence on the potential impact of trained immunity on the pathophysiology of MAFLD, shedding light on the complex immunobiology of the disease and providing novel potential therapeutic strategies to restrain the burden of the disease.
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Inmunidad Innata , Hepatopatías , Humanos , Inmunidad Entrenada , Memoria InmunológicaRESUMEN
BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disorder in which excessive CD4+ T-cell activation and imbalanced effector T-cell differentiation play critical roles. Recent studies have implied a potential association between posttranscriptional N6-methyladenosine (m6A) modification and CD4+ T-cell-mediated humoral immunity. However, how this biological process contributes to lupus is not well understood. In this work, we investigated the role of the m6A methyltransferase like 3 (METTL3) in CD4+ T-cell activation, differentiation, and SLE pathogenesis both in vitro and in vivo. METHODS: The expression of METTL3 was knocked down and METTL3 enzyme activity was inhibited using siRNA and catalytic inhibitor, respectively. In vivo evaluation of METTL3 inhibition on CD4+ T-cell activation, effector T-cell differentiation, and SLE pathogenesis was achieved using a sheep red blood cell (SRBC)-immunized mouse model and a chronic graft versus host disease (cGVHD) mouse model. RNA-seq was performed to identify pathways and gene signatures targeted by METTL3. m6A RNA-immunoprecipitation qPCR was applied to confirm the m6A modification of METTL3 targets. RESULTS: METTL3 was defective in the CD4+ T cells of SLE patients. METTL3 expression varied following CD4+ T-cell activation and effector T-cell differentiation in vitro. Pharmacological inhibition of METTL3 promoted the activation of CD4+ T cells and influenced the differentiation of effector T cells, predominantly Treg cells, in vivo. Moreover, METTL3 inhibition increased antibody production and aggravated the lupus-like phenotype in cGVHD mice. Further investigation revealed that catalytic inhibition of METTL3 reduced Foxp3 expression by enhancing Foxp3 mRNA decay in a m6A-dependent manner, hence suppressing Treg cell differentiation. CONCLUSION: In summary, our findings demonstrated that METTL3 was required for stabilizing Foxp3 mRNA via m6A modification to maintain the Treg differentiation program. METTL3 inhibition contributed to the pathogenesis of SLE by participating in the activation of CD4+ T cells and imbalance of effector T-cell differentiation, which could serve as a potential target for therapeutic intervention in SLE.
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Lupus Eritematoso Sistémico , Metiltransferasas , Linfocitos T Reguladores , Animales , Ratones , Diferenciación Celular , Factores de Transcripción Forkhead/genética , Metiltransferasas/genética , Metiltransferasas/metabolismo , Linfocitos T Reguladores/metabolismoRESUMEN
Antinuclear antibodies (ANA) have been detected in children with primary immune thrombocytopaenia (ITP), but the effect of ANA titres on clinical outcomes is unclear. Liu et al. retrospectively analysed a cohort of 324 children with primary ITP with a median follow-up time of 25 months and found that patients with high-ANA titres (≥1:160) had lower platelet counts at the onset with a higher subsequent platelet count recovery rate, and additionally were at an increased risk to develop autoimmune disease. These data highlight the possible predictive potential of ANA titres with respect to platelet counts and the development of autoimmunity in children with primary ITP. Commentary on: Liu, et al. The effect of antinuclear antibody titre and its variation on outcomes in children with primary immune thrombocytopaenia. Br J Haematol 2023;202:412-421.
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Enfermedades Autoinmunes , Púrpura Trombocitopénica Idiopática , Trombocitopenia , Niño , Humanos , Anticuerpos Antinucleares/análisis , Estudios Retrospectivos , Recuento de PlaquetasRESUMEN
The gut microbiome plays a key role in influencing several pathways and functions involved in human health, including metabolism, protection against infection, and immune regulation. Perturbation of the gut microbiome is recognised as a pathogenic factor in several gastrointestinal and extraintestinal disorders, and is increasingly considered as a therapeutic target in these conditions. Faecal microbiota transplantation (FMT) is the transfer of the microbiota from healthy screened stool donors into the gut of affected patients, and is a well-established and highly effective treatment for recurrent Clostridioides difficile infection. Despite the mechanisms of efficacy of FMT not being fully understood, it has been investigated in several chronic noncommunicable disorders, with variable results. This review aims to give an overview of mechanisms of efficacy of FMT in chronic noncommunicable disorders, and to paint the current landscape of its investigation in these medical conditions, including inflammatory bowel disease (IBD), chronic liver disorders, and also extraintestinal autoimmune conditions.
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Infecciones por Clostridium , Microbioma Gastrointestinal , Microbiota , Humanos , Trasplante de Microbiota Fecal , Heces , Microbioma Gastrointestinal/fisiología , Infecciones por Clostridium/terapia , Resultado del Tratamiento , Enfermedad CrónicaRESUMEN
STUDY QUESTION: Can potential mechanisms involved in the likely concurrence of diminished ovarian reserve (DOR) and miscarriage be identified using genetic data? SUMMARY ANSWER: Concurrence between ovarian reserve and spontaneous miscarriage was observed, and may be attributed to shared genetic risk loci enriched in antigen processing and presentation and autoimmune disease pathways. WHAT IS KNOWN ALREADY: Previous studies have shown that lower serum anti-Müllerian hormone (AMH) levels are associated with increased risk of embryo aneuploidy and spontaneous miscarriage, although findings have not been consistent across all studies. A recent meta-analysis suggested that the association between DOR and miscarriage may not be causal, but rather a result of shared underlying causes such as clinical conditions or past exposure. Motivated by this hypothesis, we conducted the present analysis to explore the concurrence between DOR and miscarriage, and to investigate potential mechanisms using genetic data. STUDY DESIGN, SIZE, DURATION: Three data sources were used in the study: the clinical IVF data were retrospectively collected from an academically affiliated Reproductive Medicine Center (17 786 cycles included); the epidemiological data from the UK Biobank (UKB), which is a large-scale, population-based, prospective cohort study (35 316 white women included), were analyzed; and individual-level genotype data from the UKB were extracted for further analysis. PARTICIPANTS/MATERIALS, SETTING, METHODS: There were three modules of analysis. First, clinical IVF data were used to test the association between ovarian reserve biomarkers and the subsequent early spontaneous miscarriage risk. Second, the UKB data were used to test the association of spontaneous miscarriage history and early menopause. Third, individual-level genotype data from the UKB were analyzed to identify specific pleiotropic genes which affect the development of miscarriage and menopause. MAIN RESULTS AND THE ROLE OF CHANCE: In the analysis of clinical IVF data, the risk of early spontaneous miscarriage was 1.57 times higher in the group with AMH < 1.1 ng/ml group (P < 0.001), 1.62 times for antral follicular count <5 (P < 0.001), and 1.39 times for FSH ≥10 mIU/ml (P < 0.001) in comparison with normal ovarian reserve groups. In the analysis of UKB data, participants with a history of three or more miscarriages had a one-third higher risk of experiencing early menopause (odds ratio: 1.30, 95% CI 1.13-1.49, P < 0.001), compared with participants without spontaneous miscarriage history. We identified 158 shared genetic risk loci that affect both miscarriage and menopause, which enrichment analysis showed were involved in antigen processing and presentation and autoimmune disease pathways. LIMITATIONS, REASONS FOR CAUTION: The analyses of the UKB data were restricted to participants of European ancestry, as 94.6% of the cohort were of white ethnicity. Further studies are needed in non-white populations. Additionally, maternal age at the time of spontaneous miscarriage was not available in the UKB cohort, therefore we adjusted for age at baseline assessment in the models instead. It is known that miscarriage rate in IVF is higher compared to natural conception, highlighting a need for caution when generalizing our findings from the IVF cohort to the general population. WIDER IMPLICATIONS OF THE FINDINGS: Our findings have implications for IVF clinicians in terms of patient counseling on the prognosis of IVF treatment, as well as for genetic counseling regarding miscarriage. Our results highlight the importance of further research on the shared genetic architecture and common pathophysiological basis of DOR and miscarriage, which may lead to new therapeutic opportunities. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the Hunan Youth Science and Technology Innovation Talent Project (2020RC3060), the International Postdoctoral Exchange Fellowship Program (Talent-Introduction Program, YJ20220220), the fellowship of China Postdoctoral Science Foundation (2022M723564), and the Natural Science Foundation of Hunan Province, China (2023JJ41016). This work has been accepted for poster presentation at the 39th Annual Meeting of ESHRE, Copenhagen, Denmark, 25-28 June 2023 (Poster number: P-477). The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: N/A.
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Aborto Espontáneo , Enfermedades Autoinmunes , Menopausia Prematura , Enfermedades del Ovario , Reserva Ovárica , Embarazo , Humanos , Femenino , Adolescente , Aborto Espontáneo/epidemiología , Estudios Retrospectivos , Estudios Prospectivos , Hormona Antimülleriana , Fertilización In Vitro/métodosRESUMEN
BACKGROUND: Polybrominated biphenyls (PBBs), a class of endocrine disrupting chemicals, were the main chemicals present in one of the largest industrial accidents in the United States. We investigated the association between serum PBB-153 levels and autoimmune disorders among members of the Michigan PBB Registry. METHODS: Eight hundred and ninety-five members of the registry had both a serum PBB-153 measurement and had completed one or more questionnaires about autoimmune disorders. Autoimmune disorders were examined collectively and within specific organ systems. Sex-stratified unadjusted and adjusted log-binomial models were used to examine the association between tertiles of serum PBB-153 levels and autoimmune disorders. Models were adjusted by lifestage at exposure (in utero, childhood, adulthood), smoking history (never, past, current), and total serum lipid levels (continuous). We utilized cubic spline models to investigate non-linearity between serum PBB-153 levels and the prevalence of autoimmune disorders. RESULTS: Approximately 12.9% and 20.7% of male and female participants reported having one or more autoimmune disorders, respectively. After adjustment for potential confounders, we observed no association between PBB-153 tertiles and the composite classification of 'any autoimmune disorder' in either sex. We observed some evidence for an association between serum PBB-153 levels and rheumatoid arthritis in males and females; however, this was not statistically significant in females. We also observed some evidence for an association between serum PBB-153 levels and neurological- and thyroid-related autoimmune disorders in females, but again this was not statistically significant. Additionally, we identified dose-response curves for serum PBB-153 levels and the prevalence of autoimmune disorders that differed by lifestage of exposure and sex. CONCLUSIONS: We observed some evidence that increasing serum PBB-153 levels were associated with three specified autoimmune disorders. Studies focusing on these three autoimmune disorders and the potential non-linear trend differences by lifestage of exposure warrant further investigation.