UNCovering new causes of monogenic systemic lupus erythematosus.

UNC93B1 is essential for the stability and endosomal trafficking of nucleic-acid sensing Toll-like receptors (TLRs) including TLR7 and TLR8. Increased TLR7 responses are associated with lupus autoimmunity in both mice and humans. In a recent article, Al-Azab et al. demonstrate the role of a variant of UNC93B1 (p.V117L) in the induction of pediatric systemic lupus erythematosus in patients and in mice through TLR7/8 hyperresponsiveness. They also highlight a potential role for the pharmacological inhibition of interleukin-1 receptor-associated kinase (IRAK) 1 and/or 4 in ameliorating disease.

The Role of the Nrf2 Pathway in Airway Tissue Damage Due to Viral Respiratory Infections.

Respiratory viruses constitute a significant cause of illness and death worldwide. Respiratory virus-associated injuries include oxidative stress, ferroptosis, inflammation, pyroptosis, apoptosis, fibrosis, autoimmunity, and vascular injury. Several studies have demonstrated the involvement of the nuclear factor erythroid 2-related factor 2 (Nrf2) in the pathophysiology of viral infection and associated complications. It has thus emerged as a pivotal player in cellular defense mechanisms against such damage. Here, we discuss the impact of Nrf2 activation on airway injuries induced by respiratory viruses, including viruses, coronaviruses, rhinoviruses, and respiratory syncytial viruses. The inhibition or deregulation of Nrf2 pathway activation induces airway tissue damage in the presence of viral respiratory infections. In contrast, Nrf2 pathway activation demonstrates protection against tissue and organ injuries. Clinical trials involving Nrf2 agonists are needed to define the effect of Nrf2 therapeutics on airway tissues and organs damaged by viral respiratory infections.

Vitamin C Supplementation in the Treatment of Autoimmune and Onco-Hematological Diseases: From Prophylaxis to Adjuvant Therapy.

Vitamin C is a water-soluble vitamin introduced through the diet with anti-inflammatory, immunoregulatory, and antioxidant activities. Today, this vitamin is integrated into the treatment of many inflammatory pathologies. However, there is increasing evidence of possible use in treating autoimmune and neoplastic diseases. We reviewed the literature to delve deeper into the rationale for using vitamin C in treating this type of pathology. There is much evidence in the literature regarding the beneficial effects of vitamin C supplementation for treating autoimmune diseases such as Systemic Lupus Erythematosus (SLE) and Rheumatoid Arthritis (RA) and neoplasms, particularly hematological neoplastic diseases. Vitamin C integration regulates the cytokines microenvironment, modulates immune response to autoantigens and cancer cells, and regulates oxidative stress. Moreover, integration therapy has an enhanced effect on chemotherapies, ionizing radiation, and target therapy used in treating hematological neoplasm. In the future, integrative therapy will have an increasingly important role in preventing pathologies and as an adjuvant to standard treatments.

[Rare Autoimmune Diseases Role of Genetics - Example of Systemic Lupus Erythematosus]. / Maladies auto-immunes rares : place de la génétique, exemple du lupus systémique.

Systemic lupus erythematosus (SLE) presents a complex clinical landscape with diverse manifestations, suggesting a multifactorial etiology. However, the identification of rare monogenic forms of the disease has shed light on specific genetic defects underlying SLE pathogenesis, offering valuable insights into its underlying mechanisms and clinical heterogeneity. By categorizing these monogenic forms based on the implicated signaling pathways, such as apoptotic body clearance, type I interferon signaling, JAK-STAT pathway dysregulation, innate immune receptor dysfunction and lymphocytic abnormalities, a more nuanced understanding of SLE's molecular basis emerges. Particularly in pediatric populations, where monogenic forms are more prevalent, routine genetic testing becomes increasingly important, with a diagnostic yield of approximately 10% depending on the demographic and methodological factors involved. This approach not only enhances diagnostic accuracy but also informs personalized treatment strategies tailored to the specific molecular defects driving the disease phenotype.

Title: Maladies auto-immunes rares : place de la génétique, exemple du lupus systémique. Abstract: Le lupus érythémateux systémique (LES) est une maladie auto-immune chronique caractérisée par une grande hétérogénéité clinique. Certaines formes rares de LES sont causées par des mutations génétiques spécifiques, contrairement à la nature multifactorielle généralement associée à la maladie. Ces formes monogéniques ont été décrites particulièrement dans les cas de LES à début pédiatrique. Leur découverte a permis une meilleure compréhension de la physiopathologie du LES, mettant en lumière la grande complexité des présentations cliniques. Nous proposons ici une classification basée sur les voies de signalisation sous-jacentes, impliquant la clairance des corps apoptotiques et des complexes immuns, les interférons de type I, les voies JAK-STAT, les récepteurs de l'immunité innée et les fonctions lymphocytaires. Dans les formes pédiatriques, un test génétique devrait être proposé systématiquement avec un rendement diagnostique autour de 10 % selon la population et les approches utilisées.

Unveiling the intricacies of COVID-19: Autoimmunity, multi-organ manifestations and the role of autoantibodies.

COVID-19 is a severe infectious disease caused by a SARS-CoV-2 infection. It has caused a global pandemic and can lead to acute respiratory distress syndrome (ARDS). Beyond the respiratory system, the disease manifests in multiple organs, producing a spectrum of clinical symptoms. A pivotal factor in the disease's progression is autoimmunity, which intensifies its severity and contributes to multi-organ injuries. The intricate interaction between the virus' spike protein and human proteins may engender the generation of autoreactive antibodies through molecular mimicry. This can further convolute the immune response, with the potential to escalate into overt autoimmunity. There is also emerging evidence to suggest that COVID-19 vaccinations might elicit analogous autoimmune responses. Advanced technologies have pinpointed self-reactive antibodies that target diverse organs or immune-modulatory proteins. The interplay between autoantibody levels and multi-organ manifestations underscores the importance of regular monitoring of serum antibodies and proinflammatory markers. A combination of immunosuppressive treatments and antiviral therapy is crucial for managing COVID-19-associated autoimmune diseases. The review will focus on the generation of autoantibodies in the context of COVID-19 and their impact on organ health.

Sex-specific differences in SLE - Significance in the experimental setting of inflammation and kidney damage in MRL-Faslpr mice.

Animal models are an important tool in the research of chronic autoimmune diseases, like systemic lupus erythematosus (SLE). MRL-Faslpr mice are one of different lupus models that develop spontaneously an SLE-like disease with autoantibodies and immune complex deposition that leads into damage of different organs. In contrast to human SLE, both sexes of MRL-Faslpr mice develop a similar autoimmune disease. Due to the sex bias in human and the delayed disease progression in male MRL-Faslpr mice, the majority of studies have been performed in female mice. To determine the suitability of male MRL-Faslpr mice for SLE research, especially with regard to the 3 R-principle and animal welfare, analyses of phenotype, inflammation and damage with focus on kidney and spleen were performed in mice of both sexes. Female mice developed lymphadenopathy and skin lesions earlier as males. At an age of 3.5 month, more immune cells infiltrated kidney and spleen in females compared to males. At the age of 5 months, however, substantially less sex-specific differences were detected. Since other studies have shown differences between both sexes on other manifestations like autoimmune pancreatitis and Sjögren syndrome in MRL-Faslpr mice, the use of male mice as part of 3 R-principle and animal welfare must be carefully considered.

Thyroid ultrasonic changes relate to implantation failure in euthyroid women with thyroid autoimmunity undergoing in vitro fertilization/intracytoplasmic sperm injection.

OBJECTIVE: To determine whether ultrasonic manifestations of Hashimoto's thyroiditis (HT) related to embryo qualities or pregnancy outcomes in women with thyroid autoimmunity (TAI) undergoing in vitro fertilization/intracytoplasmic sperm injection. METHODS: Our study was a retrospective cohort study. A total of 589 euthyroid women enrolled from January 2017 to December 2019. 214 TAI women and 375 control women were allocated in each group according to serum levels of thyroid peroxidase antibodies (TPOAb) and/or anti-thyroglobulin antibodies (TgAb). Basal serum hormone levels and thyroid ultrasound were assessed, embryo qualities, pregnancy outcomes were collected from medical records. Diagnosis of thyroid ultrasound was used for subanalysis. Logistic regression was used to evaluate outcomes of embryo development and pregnancy. RESULTS: Implantation rate was significantly lower in euthyroid women with TAI compared with control group (TAI group: 65.5% vs. Control group: 73.0%, adjusted OR (95% CI): 0.65 (0.44, 0.97), p = 0.04). We further stratified TAI group into two groups: one group with HT features under ultrasound and another group with normal thyroid ultrasound. After regression analysis, TAI women with HT morphological changes had a lower chance of implantation compared with control group (TAI group with HT: 64.1% vs. Control group: 73.0%, adjusted OR (95% CI): 0.63 (0.41, 0.99), p = 0.04), while there was no significant difference on implantation rate between TAI women with normal thyroid ultrasound and control group. Other outcomes, such as embryo qualities and pregnancy rate, were comparable between TAI and control groups. CONCLUSIONS: A higher risk of implantation failure was seen among euthyroid women with TAI, especially women with HT morphological changes under ultrasound. The underlying mechanisms of implantation failure among euthyroid HT patients need further research.

Impaired embryo development potential associated with thyroid autoimmunity in euthyroid infertile women with diminished ovarian reserve.

Purpose: The aim of this study was to evaluate the associations of thyroid autoimmunity (TAI) with the number of oocytes retrieved (NOR), fertilization rate (FR), and embryo quality (EQ) in euthyroid women with infertility and diminished ovarian reserve (DOR). Methods: This retrospective cohort study involved 1,172 euthyroid women aged 20-40 years with infertility and DOR who underwent an oocyte retrieval cycle. TAI was diagnosed in the presence of serum thyroperoxidase antibody (TPOAb) concentrations higher than 34 IU/ml and/or serum thyroglobulin antibody (TgAb) concentrations exceeding 115.0 IU/ml. Among these women, 147 patients with TAI were classified as the TAI-positive group, while 1,025 patients without TAI were classified as the TAI-negative group. Using generalized linear models (GLMs) adjusted for confounding factors, we evaluated the associations of TAI and the serum TPOAb and TgAb concentrations and NOR, FR, and EQ in this study's subjects. The TPOAb and TGAb values were subjected to log10 transformation to reduce skewness. Logistic regression models were used to estimate the effects of TPOAb and TgAb concentrations on the probabilities of achieving a high NOR (≥7) and high FR (>60%). Results: For the whole study population, women with TAI had a significantly lower NOR and poorer EQ than women without TAI (P < 0.001 for both). Interestingly, in the TSH ≤2.5 subgroup, the TAI-positive group also had a significantly lower NOR and poorer EQ than the TAI-negative group (P < 0.001 for both). Furthermore, negative associations were observed between log10(TPOAb) concentrations and NOR and the number of high-quality embryos and available embryos (P < 0.05 for all). The log10(TgAb) concentrations were inversely associated with NOR and the number of high-quality embryos (P < 0.05 for all). In the regression analysis, the log10(TPOAb) concentrations had lower probabilities of achieving a high NOR [adjusted odds ratio (aOR): 0.56; 95% confidence interval (95% CI) 0.37, 0.85; P = 0.007]. Conclusions: TAI and higher TPOAb and TgAb concentrations were shown to be associated with reductions in the NOR and EQ in the study population. Our findings provide further evidence to support systematic screening and treatment for TAI in euthyroid women with infertility and DOR.

The phenotypic landscape of primary biliary cholangitis and autoimmune hepatitis variants.

Autoimmune Hepatitis (AIH) and Primary Biliary Cholangitis (PBC) stand as distinct diseases, yet occasionally intertwine with overlapping features, posing diagnostic and management challenges. This recognition traces back to the 1970s, with initial case reports highlighing this complexity. Diagnostic scoring systems like IAIHG and simplified criteria for AIH were introduced but are inherently limited in diagnosing variant syndromes. The so-called Paris Criteria offer a diagnostic framework with high sensitivity and specificity for variant syndromes, although disagreements among international guidelines persist. Histological findings in AIH and PBC may exhibit overlapping features, rendering histology alone inadequate for a definitive diagnosis. Autoantibody profiles could be helpful, but similarly cannot be considered alone to reach a solid and consistent evaluation. Treatment strategies vary based on the predominant features observed. Individuals with overlapping characteristics favoring AIH ideally benefit from corticosteroids, while patients primarily manifesting PBC features should initially receive treatment with choleretic drugs like ursodeoxycholic acid (UDCA).

SOCS1 is a critical checkpoint in immune homeostasis, inflammation and tumor immunity.

The Suppressor of Cytokine Signaling (SOCS) family proteins are important negative regulators of cytokine signaling. SOCS1 is the prototypical member of the SOCS family and functions in a classic negative-feedback loop to inhibit signaling in response to interferon, interleukin-12 and interleukin-2 family cytokines. These cytokines have a critical role in orchestrating our immune defence against viral pathogens and cancer. The ability of SOCS1 to limit cytokine signaling positions it as an important immune checkpoint, as evidenced by the detection of detrimental SOCS1 variants in patients with cytokine-driven inflammatory and autoimmune disease. SOCS1 has also emerged as a key checkpoint that restricts anti-tumor immunity, playing both a tumor intrinsic role and impacting the ability of various immune cells to mount an effective anti-tumor response. In this review, we describe the mechanism of SOCS1 action, focusing on the role of SOCS1 in autoimmunity and cancer, and discuss the potential for new SOCS1-directed cancer therapies that could be used to enhance adoptive immunotherapy and immune checkpoint blockade.

Aberrant immunity in the oral cavity-a link with rheumatoid arthritis?

There are well established epidemiological links between rheumatoid arthritis and periodontitis. Recent data have started to shed light on the mechanisms that might underlie the relationship between these two complex diseases. Unravelling the roles of distinct pathways involved in these mechanisms has the potential to yield novel preventative and therapeutic strategies for both diseases. Perhaps most intriguingly, this represents an area where understanding the biology in the oral cavity might reveal fundamental advances in understanding immune regulation and the relationships between the host and microbiome. Here we seek to discuss aspects of the adaptive immune response that might link periodontitis and rheumatoid arthritis.

High salt diet alleviates disease severity in native experimental autoimmune uveitis.

Background: Recent studies reported a link between high salt diet (HSD) and clinical exacerbation in mouse models of autoimmune diseases, mainly through the induction of pathogenic Th17 cells and/or HSD-induced dysbiosis. However, the topic remains controversial and not fully understood. Purpose: In this study, we investigated the effects of HSD on the development of experimental autoimmune uveitis (EAU) in C57BL/6J mice. Methods and results: Unexpectedly, our data showed a significant attenuating effect of HSD on disease severity of native EAU, induced by direct immunization with IRBP peptide. That said, HSD had no effect on EAU disease severity induced by adoptive transfer of semi-purified auto-reactive IRBP-specific T lymphocytes. Accordingly, HSD did not affect IRBP-specific systemic afferent immune response as attested by no HSD-linked changes in T lymphocytes proliferation, cytokine production and Treg proportion. Gut microbiota analysis from cecal samples in naïve and EAU mice demonstrated that HSD affected differentially α-diversity between groups, whereas ß-diversity was significantly modified in all groups. Unknown Tannerellaceae was the only taxon associated to HSD exposure in all treatment groups. Interestingly, a significantly higher abundance of unknown Gastranaerophilales, with potential anti-inflammatory properties, appeared in HSD-fed native EAU mice, only. Discussion: In conclusion, our study suggests a possible impact of HSD on gut microbiota composition and consequently on development and clinical severity of EAU. Further studies are required to investigate the potential beneficial role of Gastranaerophilales in EAU.

STING trafficking activates MAPK-CREB signaling to trigger regulatory T cell differentiation.

The Type-I interferon (IFN-I) response is the major outcome of stimulator of interferon genes (STING) activation in innate cells. STING is more abundantly expressed in adaptive T cells; nevertheless, its intrinsic function in T cells remains unclear. Intriguingly, we previously demonstrated that STING activation in T cells activates widespread IFN-independent activities, which stands in contrast to the well-known STING-mediated IFN response. Here, we have identified that STING activation induces regulatory T cells (Tregs) differentiation independently of IRF3 and IFN. Specifically, the translocation of STING from the endoplasmic reticulum to the Golgi activates mitogen-activated protein kinase (MAPK) activity, which subsequently triggers transcription factor cAMP response element-binding protein (CREB) activation. The activation of the STING-MAPK-CREB signaling pathway induces the expression of many cytokine genes, including interleukin-2 (IL-2) and transforming growth factor-beta 2 (TGF-ß2), to promote the Treg differentiation. Genetic knockdown of MAPK p38 or pharmacological inhibition of MAPK p38 or CREB markedly inhibits STING-mediated Treg differentiation. Administration of the STING agonist also promotes Treg differentiation in mice. In the Trex1-/- autoimmune disease mouse model, we demonstrate that intrinsic STING activation in CD4+ T cells can drive Treg differentiation, potentially counterbalancing the autoimmunity associated with Trex1 deficiency. Thus, STING-MAPK-CREB represents an IFN-independent signaling axis of STING that may have profound effects on T cell effector function and adaptive immunity.

Effects of low-dose methotrexate with MMI in patients with Graves' disease: results of a randomized clinical trial.

CONTEXT: Supplemental methotrexate (MTX) may affect the clinical course of Graves' disease (GD). OBJECTIVE: Evaluate efficacy of add-on MTX on medical treatment in GD. DESIGN: Prospective, open-label, randomized supplementation controlled trial. SETTING: Academic endocrine outpatient clinic. PATIENTS: One hundred and fifty-three untreated hyperthyroid patients with GD. INTERVENTION: Patients received MTX 10 mg/d with methimazole (MMI) or MMI only. MTX and MMI were discontinued at months 12-18 in euthyroid patients. MAIN OUTCOME MEASURES: Discontinuation rate at months 18 in each group. RESULTS: In the MTX with MMI group, the discontinuation rate was higher than the MMI group at months 15-18 (50.0 vs. 33.3%, P=0.043, 95% CI 1.020 to 3.922; and 55.6 vs 38.9%, P=0.045, 95%CI 1.011 to 3.815, respectively). The decrease in TRAb levels in the MTX with MMI group was significant from baseline to months 6 compared to the MMI alone group [MTX+MMI 67.22% (43.12-80.32), MMI 54.85% (33.18-73.76), P= 0.039) and became more significant from months 9 [MTX+MMI 77.79% (62.27-88.18), MMI 69.55% (50.50-83.22), P= 0.035] to months 18 (P < 0.01 in 15-18 months). A statistically significant difference between the levels of TRAb in the MTX with MMI group and the MMI group at 9-18 months. There were no significant differences in the levels of FT3, FT4 and TSH between two groups. No serious drug-related adverse events were observed in both groups(P=0.771). CONCLUSIONS: Supplemental MTX with MMI resulted in higher discontinuation rate and improvement in decreased TRAb levels to homeostatic levels faster than methimazole treatment alone at months 12-18.

An update on the endocrine manifestations of antiphospholipid syndrome.

Antiphospholipid Syndrome (APS), characterized by hypercoagulability and pregnancy morbidity, poses a significant clinical challenge when involving organ systems, such as the endocrine system. APS can directly and indirectly influence the anterior and posterior lobes of the pituitary gland. The thyroid gland exhibits involvement, especially in patients with positive anticardiolipin antibodies, yet the clinical significance of the relationship with APS remains elusive. The pancreas, often overlooked, manifests in diverse ways, from pancreatitis to implications in diabetes. Adrenal insufficiency emerges as a common endocrine manifestation of APS, with adrenal hemorrhage or infarction being a presenting manifestation. Adrenal gland involvement has also been reported in the context of catastrophic APS. Pregnancy complications and infertility might be effects of APS on the female ovaries, while testicular torsion and decreased sperm concentration and total sperm count have been reported as rare effects of APS on male testes.

tRNA-derived fragments in T lymphocyte-beta cell crosstalk and in type 1 diabetes pathogenesis in NOD mice.

AIMS/HYPOTHESIS: tRNAs play a central role in protein synthesis. Besides this canonical function, they were recently found to generate non-coding RNA fragments (tRFs) regulating different cellular activities. The aim of this study was to assess the involvement of tRFs in the crosstalk between immune cells and beta cells and to investigate their contribution to the development of type 1 diabetes. METHODS: Global profiling of the tRFs present in pancreatic islets of 4- and 8-week-old NOD mice and in extracellular vesicles released by activated CD4+ T lymphocytes was performed by small RNA-seq. Changes in the level of specific fragments were confirmed by quantitative PCR. The transfer of tRFs from immune cells to beta cells occurring during insulitis was assessed using an RNA-tagging approach. The functional role of tRFs increasing in beta cells during the initial phases of type 1 diabetes was determined by overexpressing them in dissociated islet cells and by determining the impact on gene expression and beta cell apoptosis. RESULTS: We found that the tRF pool was altered in the islets of NOD mice during the initial phases of type 1 diabetes. Part of these changes were triggered by prolonged exposure of beta cells to proinflammatory cytokines (IL-1ß, TNF-α and IFN-γ) while others resulted from the delivery of tRFs produced by CD4+ T lymphocytes infiltrating the islets. Indeed, we identified several tRFs that were enriched in extracellular vesicles from CD4+/CD25- T cells and were transferred to beta cells upon adoptive transfer of these immune cells in NOD.SCID mice. The tRFs delivered to beta cells during the autoimmune reaction triggered gene expression changes that affected the immune regulatory capacity of insulin-secreting cells and rendered the cells more prone to apoptosis. CONCLUSIONS/INTERPRETATION: Our data point to tRFs as novel players in the crosstalk between the immune system and insulin-secreting cells and suggest a potential involvement of this novel class of non-coding RNAs in type 1 diabetes pathogenesis. DATA AVAILABILITY: Sequences are available from the Gene Expression Omnibus (GEO) with accession numbers GSE242568 and GSE256343.

[Immunological foundations of neurological diseases]. / Immunologische Grundlagen neurologischer Erkrankungen.

BACKGROUND: Neurodegenerative diseases represent an increasing challenge in ageing societies, as only limited treatment options are currently available. OBJECTIVE: New research methods and interdisciplinary interaction of different disciplines have changed the way neurological disorders are viewed and paved the way for the comparatively new field of neuroimmunology, which was established in the early 1980s. Starting from neurological autoimmune diseases, such as multiple sclerosis, knowledge about the involvement of immunological processes in other contexts, such as stroke or traumatic brain injury, has been significantly expanded in recent years. MATERIAL AND METHODS: This review article provides an overview of the role of the immune system and the resulting potential for novel treatment approaches. RESULTS: The immune system plays a central role in fighting infections but is also able to react to the body's own signals under sterile conditions and cause inflammation and subsequent adaptive immune responses through the release of immune mediators and the recruitment and differentiation of certain immune cell types. This can be beneficial in initiating healing processes; however, chronic inflammatory conditions usually have destructive consequences for the tissue and the organism and must be interrupted. CONCLUSION: It is now known that different cells of the immune system play an important role in neurological diseases. Regulatory mechanisms, which are mediated by regulatory T cells or Th2 cells, are usually associated with a good prognosis, whereas inflammatory processes and polarization towards Th1 or Th17 have a destructive character. Novel immunomodulators, which are also increasingly being used in cancer treatment, can now be used in a tissue-specific manner and therefore offer great potential for use in neurological diseases.