Autoimmune Pathways Research Articles

Increased prevalence of antinuclear antibody positivity in central centrifugal cicatricial alopecia patients

Background: Central centrifugal cicatricial alopecia (CCCA) is a primary scarring alopecia predominantly affecting Black women. Autoimmune mechanisms, including antinuclear antibody (ANA) positivity, have been hypothesized to contribute to its pathogenesis but remain underexplored. Methods: Using the TriNetX database (2004–2024), we identified Black women with CCCA and controls with other primary scarring alopecias. Patients were propensity score matched by current age and age at diagnosis. We compared the prevalence of ANA positivity and autoimmune comorbidities before and after alopecia diagnosis. Statistical significance was defined as an adjusted p-value <0.05. Results: Among 5,811 CCCA patients and matched controls, CCCA patients were more likely to have positive ANA (11.8% vs. 2.0%, p<0.001) and systemic lupus erythematosus (SLE) post-diagnosis (0.9% vs. 0.3%, p=0.007). They were less likely to have type 1 diabetes (T1DM) pre-diagnosis (2.9% vs. 4.8%, p=0.007) and post-diagnosis (0.8% vs. 1.3%, p=0.024). No significant differences were found in other autoimmune diseases. Conclusion: CCCA patients had higher prevalence of ANA positivity and SLE, supporting potential autoimmune involvement. However, screening for other autoimmune diseases in asymptomatic CCCA patients may not be necessary. Further research is needed to clarify the interplay between autoimmune and metabolic pathways in CCCA.

Gut Microbiota Modulation: A Novel Strategy for Rheumatoid Arthritis Therapy.

Rheumatoid arthritis (RA) is a chronic autoimmune disease that leads to joint inflammation, progressive tissue damage and significant disability, severely impacting patients' quality of life. While the exact mechanisms underlying RA remain elusive, growing evidence suggests a strong link between intestinal microbiota dysbiosis and the disease's development and progression. Differences in microbial composition between healthy individuals and RA patients point to the role of gut microbiota in modulating immune responses and promoting inflammation. Therapies targeting microbiota restoration have demonstrated promise in improving treatment efficacy, enhancing patient outcomes and slowing disease progression. However, the complex interplay between gut microbiota and autoimmune pathways in RA requires further investigation to establish causative relationships and mechanisms. Here, we review the current understanding of the gut microbiota's role in RA pathogenesis and its potential as a therapeutic target.

Analysis of vitamin D metabolism, thyroid and autoimmune markers in the vitiligo pathways and their possible interaction with sleep.

Vitiligo is an autoimmune skin disease that can be influenced by stress, including that resulting from sleep deprivation and sleep disturbances. Sleep is essential in the regulation of several hormonal, metabolic and autoimmune pathways that may have important roles in vitiligo. This study aimed to investigate the potential interplay between hormonal, metabolic, and autoimmune markers in vitiligo patients, and the possible influence of sleep quality in these vitiligo pathways. A cohort of 30 vitiligo patients and 26 healthy controls were assessed for various laboratory markers, including thyroid-stimulating hormone (TSH), parathyroid hormone (PTH), serum calcium, 1.25(OH)2D, 25(OH)D, anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-TG), and antinuclear antibodies (ANA). The study evaluated sleep quality using the Pittsburgh Sleep Quality Index (PSQI). Positive anti-TPO were found in the vitiligo group, but did not in the control group. Vitamin D 25(OH)D mean levels were clinically insufficient in both groups (< 30mg/dL). Reactive ANA was analyzed with 2 variables related to vitiligo: phototherapy and skin activity. No statistical correlation was found in the chi-square test on this relationship. Descriptive findings have shown that the positivity to anti-TPO and anti-TG, associated or not with reactive ANA, was higher in vitiligo group. Great part (85.7%) of vitiligo group were "poor sleepers" (PSQI > 5), which has increased (88.2%) when considering only individuals with signs of vitiligo activity. Autoimmune hypothyroidism and positive anti-TPO are expected in vitiligo, although this marker is not usually measured in the first laboratory screening to this disease. Adequate vitamin D levels may be a key adjuvant in skin pigmentation, and be related to sleep quality and immune regulation, as this vitamin can be related to better sleep and immunomodulation in autoimmune diseases. Evaluating ANA before phototherapy can be controversial, but it should be considered in cases with a poor response to this treatment, or when there is a higher risk of other autoimmune diseases. Poor sleep predominated in the vitiligo group, based on PSQI scores that reported worse subjective sleep in these patients. Worse sleep predominated in individuals with signs of skin activity and reactive autoimmune markers. Screening these components could be important in the management of vitiligo, as maintaining body homeostasis can help to improve the disease course. Sleep should be considered as a potential modulator of several multidirectional vitiligo pathways.

Increased Cytokine Levels in Seronegative Myositis: Potential Th17 Immune Response Implications

Th17 cells are known for producing IL-17 and their role in the pathogenesis of various autoimmune diseases, including myositis. Likewise, the participation of the IL-23/IL-17 pathway in autoimmunity has been confirmed. In this study, we aimed to evaluate the behavior of cytokines in myositis, focusing on the autoantibodies profile and the myositis core set measures. Twenty-five myositis patients were enrolled in this cross-sectional study. An expert rheumatologist evaluated the myositis core set measures. Serum levels of cytokines and chemokines were quantified using the LEGENDplex Multi-Analyte Flow Assay Kit from BioLegend. The autoantibodies detection was carried out using the line-blot assay kit Euroline: Autoimmune Inflammatory Myopathies from EUROIMMUN. We found higher serum levels of IL-33, CXCL8, IL-6, IL-23, and IL-12p70 in seronegative patients. A multiple linear regression analysis revealed that MYOACT scores could be predicted by the increment of IL-23 and the decrement of CCL2, IL-10, and CXCL8 serum levels. These findings suggest that the immune response in seronegative myositis patients exhibits an IL-23-driven Th17 immune response. The relevance of this discovery lies in its potential therapeutic implications. Insights into the IL-23-driven Th17 immune response in seronegative patients highlight the potential for targeted therapies aimed at modulating Th17 activity.

6770 Graves’ disease induced by COVID-19 infection in a 49 year old male

Abstract Disclosure: N. Al-hosainat: None. A. Al Najada: None. T. Salar: None. S. Iqbal: None. K. Abdel Gadir: None. Introduction: Graves’ disease is an autoimmune disease causing hyperthyroidism, characterized by elevated thyrotropin-receptor antibodies. COVID-19 infection has been increasingly reported as a trigger of thyroid illness including Graves’ disease. We present a unique case of 49-year-old patient who was diagnosed with Graves’ disease after COVID-19 infection. Case description: A 49-year-old male patient with history of prediabetes presented with complaints of tremor, fatigue, generalized itching, and unintentional weight loss (30 Ibs in 6 months). He had COVID-19 infection 3 months prior. The remainder of review of systems was negative. No family history of thyroid disease. On exam, the patient had sinus tachycardia with otherwise normal vital signs. Diffuse thyromegaly was noted along with an intermittent fine tremor of the extremities. Blood work was notable for low TSH &amp;lt;0.01 uIU/mL, elevated free T4 (3.4 ng/dL), free T3 (17.6ng/dL), and TSH receptor antibody (12 IU/L). Thyroid ultrasound showed mild goiter with 2 nodules, one of which was TIRADS 4 and 1.5cm. This nodule was biopsied and found to be benign. Radioactive iodine uptake scan revealed homogeneous diffuse increased thyroid uptake. The diagnosis of Graves’ disease was made, and the patient was started on propranolol and methimazole with significant improvement of his symptoms and his laboratory tests normalizing. Discussion: Graves' disease is an autoimmune disease, characterized by hyperthyroidism, goiter, occasional orbitopathy and dermopathy. Caused by antibodies against thyroid-stimulating hormone receptors which stimulate thyroid hormone secretion and thyroid growth. Treatment is aimed to decrease thyroid hormone synthesis by either a Thionamide, radioiodine ablation, or surgery. Remission rates with antithyroid drugs average under 40 percent after one to two years of treatment and could exceed 80 percent after 5 to 10 years of treatment. COVID-19 is a multi-system disease, caused by SARS-CoV-2 virus, transmitted by large droplets and small particle aerosols, was declared a pandemic in 2020 and affected millions of people worldwide. There is emerging data showing the association of COVID-19 with various thyroid diseases including thyroiditis and relapse of known Graves' disease after the infection. We present a case of newly diagnosed Graves’ disease after COVID-19 infection in a patient with no personal or family history of such disease which raises the concern of autoimmune pathway activation induced by the infection. The onset of Graves’ disease after COVID-19 infection does not depend on the presence of pre-existing thyroid pathology and in this case responded well to antithyroid medication. Conclusion: COVID-19 can lead to the development of a range of medical illnesses. In patients who develop symptoms of thyrotoxicosis, Graves’ disease should be suspected, investigated, and treated appropriately Presentation: 6/3/2024

Immune Jumping in Autoimmune Long-Covid.

This Long-Covid disease, mild or severe, is multiorgan or system-wide, spanning from fatigue to clotting abnormalities and autoantibody. The spectrum of different symptoms in Long-Covid diseases makes it difficult to point to a common immunopathogenic etiology. Different immune pathways are presented and critically evaluated. A hypothesis is advanced that indicates autoimmune reactions as cause for Long-Covid disease. The immune network pathway describes a redirection of the nominal anti-SARS-CoV response towards an autoimmune target. Several therapeutic interventions are suggested to suppress the autoimmune pathway.

Autoimmune Diseases Following Environmental Disasters: A Narrative Review of the Literature.

Environmental disasters are extreme environmental processes such as earthquakes, volcanic eruptions, landslides, tsunamis, floods, cyclones, storms, wildfires and droughts that are the consequences of the climate crisis due to human intervention in the environment. Their effects on human health have alarmed the global scientific community. Among them, autoimmune diseases, a heterogeneous group of disorders, have increased dramatically in many parts of the world, likely as a result of changes in our exposure to environmental factors. However, only a limited number of studies have attempted to discover and analyze the complex association between environmental disasters and autoimmune diseases. This narrative review has therefore tried to fill this gap. First of all, the activation pathways of autoimmunity after environmental disasters have been analyzed. It has also been shown that wildfires, earthquakes, desert dust storms and volcanic eruptions may damage human health and induce autoimmune responses to inhaled PM2.5, mainly through oxidative stress pathways, increased pro-inflammatory cytokines and epithelial barrier damage. In addition, it has been shown that heat stress, in addition to increasing pro-inflammatory cytokines, may also disrupt the intestinal barrier, thereby increasing its permeability to toxins and pathogens or inducing epigenetic changes. In addition, toxic volcanic elements may accelerate the progressive destruction of myelin, which may potentially trigger multiple sclerosis. The complex and diverse mechanisms by which vector-borne, water-, food-, and rodent-borne diseases that often follow environmental diseases may also trigger autoimmune responses have also been described. In addition, the association between post-disaster stress and the onset or worsening of autoimmune disease has been demonstrated. Given all of the above, the rapid restoration of post-disaster health services to mitigate the flare-up of autoimmune conditions is critical.

Sterile activation of RNA-sensing pathways in autoimmunity.

RNA-sensing pathways play a pivotal role in host defense against pathogenic infections to maintain cellular homeostasis. However, in the absence of infection, certain endogenous RNAs can serve as the activators of RNA-sensing pathways as well. The inappropriate activation of RNA-sensing pathways by self-ligands leads to systemic inflammation and autoimmune diseases. In this review, we summarize current findings on the sterile activation of RNA sensors, as well as its implications in autoimmunity, inflammatory diseases, and therapeutics.

A retrospective analysis of disease epidemiology, comorbidities, treatment patterns, and healthcare resource utilization of alopecia areata in the United Arab Emirates using claims database.

Alopecia areata (AA) is an autoimmune disorder that manifests as nonscarring hair loss and imposes a substantial disease burden. The current study, using an e-claims database, assesses the disease burden, comorbidities, treatment patterns, specialties involved in the diagnosis of AA, healthcare resource utilization (HCRU), and associated costs in privately insured patients with AA in Dubai, United Arab Emirates. The retrospective longitudinal secondary study was conducted using Dubai Real-World Database e-claims data during 01 January 2014 to 30 June 2022. Patients with at least one diagnosis claim of AA during the index period (01 January 2015-30 June 2021) with continuous enrollment (one or more AA/non-AA claim in the post-index period) were included in the analysis. The patients were stratified into subcohorts based on diagnosis code and treatment patterns, as mild, moderate-to-severe, and others. Demographics, comorbidities, treatment patterns, specialists visited, and HCRU were assessed. The study included 11 851 patients with AA (mean age: mild: 37 years; moderate-to-severe: 36 years), with a male predominance (mild: 77.6%; moderate-to-severe: 60.8%). The most prevalent comorbidities in the moderate-to-severe AA subcohort were autoimmune and T-helper 2-mediated immune disorders, including contact dermatitis and eczema (62.1%), atopic dermatitis (36.1%), and asthma (36.1%). Most patients consulted dermatologists for treatment advice (mild AA: 87.4%; moderate-to-severe AA: 47.7%) and, notably, within 1 day of AA diagnosis. Topical steroids were frequently prescribed across cohorts, regardless of disease severity. Analysis of comorbidities among patients with AA indicated an additional HCRU burden among these subsets of patients. The median disease-specific HCRU cost was higher for psychological comorbidities versus autoimmune and T-helper 2-mediated immune disorders (US $224.99 vs US $103.70). There is a substantial disease and economic burden in patients with AA and associated comorbid conditions; therefore, investing in novel therapies that target the underlying autoimmune pathway may address the gap in effective management of AA.

Mechanical Basis of Lumbar Intervertebral Disk Degeneration

Abstract The etiology of degenerative disk disease (DDD) is multifactorial. Among the various factors, mechanical processes contributing to endplate or discal injuries have been discussed as the initiating events in the degenerative cascade. DDD encompasses the multitudinous changes undergone by the different structures of the spinal segment, namely intervertebral disk (IVD), facet joints, vertebral end plate (VEP), adjoining marrow (Modic changes), and vertebral body. It has been etiologically linked to a complex interplay of diverse mechanisms. Mechanically, two different mechanisms have been proposed for intervertebral disk degeneration (IVDD): endplate-driven, especially in upper lumbar levels, and annulus-driven degeneration. VEP is the weakest link of the lumbar spine, and fatigue damage can be inflicted upon them under physiological loads, leading to the initiation of DDD. Disk calcification has been put forth as another initiator of inflammation, stiffening, and abnormal stresses across the IVD. The initial mechanical disruption leads to secondary IVDD through unfavorable loading of the nucleus pulposus and annulus fibrosis. The final degenerative cascade is then propagated through a combination of biological, inflammatory, autoimmune, or metabolic pathways (impaired transport of metabolites or nutrients). Abnormal spinopelvic alignment, especially pelvic incidence, also significantly impacts the degenerative process. Hence, the etiology of DDD is multifactorial. Mechanical pathways, including VEP injuries, increased disk stiffness, and abnormal spinopelvic alignment, play a significant role in the initiation of IVDD.

Deciphering the therapeutic potential of trimetazidine in rheumatoid arthritis via targeting mi-RNA128a, TLR4 signaling pathway, and adenosine-induced FADD-microvesicular shedding: In vivo and in silico study.

Rheumatoid arthritis (RA) is a debilitating autoimmune condition characterized by chronic synovitis, joint damage, and inflammation, leading to impaired joint functionality. Existing RA treatments, although effective to some extent, are not without side effects, prompting a search for more potent therapies. Recent research has revealed the critical role of FAS-associated death domain protein (FADD) microvesicular shedding in RA pathogenesis, expanding its scope beyond apoptosis to include inflammatory and immune pathways. This study aimed to investigate the intricate relationship between mi-RNA 128a, autoimmune and inflammatory pathways, and adenosine levels in modulating FADD expression and microvesicular shedding in a Freund's complete adjuvant (FCA) induced RA rat model and further explore the antirheumatoid potency of trimetazidine (TMZ). The FCA treated model exhibited significantly elevated levels of serum fibrogenic, inflammatory, immunological and rheumatological diagnostic markers, confirming successful RA induction. Our results revealed that the FCA-induced RA model showed a significant reduction in the expression of FADD in paw tissue and increased microvesicular FADD shedding in synovial fluid, which was attributed to the significant increase in the expression of the epigenetic miRNA 128a gene in addition to the downregulation of adenosine levels. These findings were further supported by the significant activation of the TLR4/MYD88 pathway and its downstream inflammatory IkB/NFB markers. Interestingly, TMZ administration significantly improved, with a potency similar to methotrexate (MTX), the deterioration effect of FCA treatment, as evidenced by a significant attenuation of fibrogenic, inflammatory, immunological, and rheumatological markers. Our investigations indicated that TMZ uniquely acted by targeting epigenetic miRNA128a expression and elevating adenosine levels in paw tissue, leading to increased expression of FADD of paw tissue and mitigated FADD microvesicular shedding in synovial fluid. Furthermore, the group treated with TMZ showed significant downregulation of TLR4/MYD88 and their downstream TRAF6, IRAK and NF-kB. Together, our study unveils the significant potential of TMZ as an antirheumatoid candidate, offering anti-inflammatory effects through various mechanisms, including modulation of the FADD-epigenetic regulator mi-RNA 128a, adenosine levels, and the TLR4 signaling pathway in joint tissue, but also attenuation of FADD microvesicular shedding in synovial fluid. These findings further highlight the synergistic administration of TMZ and MTX as a potential approach to reduce adverse effects of MTX while improving therapeutic efficacy.

A case-control study: epigenetic age acceleration in psoriasis.

Psoriasis (PsO) is a chronic inflammatory skin condition, often accompanied by psoriatic arthritis (PsA) and linked to various comorbidities and increased mortality rates. This study aimed to explore the relationship between PsO and accelerated biological aging, specifically focusing on epigenetic DNA methylation clocks. Using a matched case-control design, 20 PsO cases were selected along with age, race, and sex-matched 20 controls without PsO from the Skin Disease Biorepository at Brown Dermatology, Inc, Providence, Rhode Island. Blood samples retrieved from both groups were analyzed for DNA methylation, and epigenetic ages were calculated using DNA methylation clocks, including Horvath, Hannum, Pheno, SkinBlood, and Grim ages. Generalized estimation equations were employed to test the differences in epigenetic and chronological ages between PsO cases and controls, as well as within various subgroups in comparison to their respective controls. There were no statistically significant differences in epigenetic ages between PsO cases and controls. However, notably, PsO cases with PsA demonstrated an accelerated PhenoAge, compared to their matched controls. This study represents a pioneering investigation into the potential link between PsO and epigenetic aging, shedding light on the possibility of accelerated epigenetic aging in PsA, possibly associated with heightened inflammatory burden. These findings emphasize the systemic impact of PsA on the aging process, prompting the need for deeper exploration into autoimmune pathways, inflammation, and epigenetic modifications underlying PsO pathogenesis and aging mechanisms. Larger-scale studies with diverse populations are imperative to discern PsO subgroups experiencing accelerated biological aging and decipher the intricate interplay between PsO, inflammation, and aging pathways.

Employing Feature Selection Algorithms to Determine the Immune State of Mice Model of Rheumatoid Arthritis.

The immune response is a dynamic process by which the body determines whether an antigen is self or nonself. The state of this dynamic process is defined by the relative balance and population of inflammatory and regulatory actors which comprise this decision making process. The goal of immunotherapy as applied to, e.g. Rheumatoid Arthritis (RA), then, is to bias the immune state in favor of the regulatory actors - thereby shutting down autoimmune pathways in the response. While there are several known approaches to immunotherapy, the effectiveness of the therapy will depend on how this intervention alters the evolution of this state. Unfortunately, this process is determined not only by the dynamics of the process, but the state of the system at the time of intervention - a state which is difficult if not impossible to determine prior to application of the therapy. To identify such states we consider a mouse model of RA (Collagen-Induced Arthritis (CIA)) immunotherapy; collect high dimensional data on T cell markers and populations of mice after treatment with a recently developed immunotherapy for CIA; and use feature selection algorithms in order to select a lower dimensional subset of this data which can be used to predict both the full set of T cell markers and populations, along with the efficacy of immunotherapy treatment.

Dietary docosahexaenoic acid supplementation inhibits acute pulmonary transcriptional and autoantibody responses to a single crystalline silica exposure in lupus-prone mice.

Workplace exposure to respirable crystalline silica (cSiO2) has been epidemiologically linked to lupus. Consistent with this, repeated subchronic intranasal cSiO2 instillation in lupus-prone NZBWF1 mice induces inflammation-/autoimmune-related gene expression, ectopic lymphoid tissue (ELT), autoantibody (AAb) production in the lung within 5 to 13 wk followed systemic AAb increases and accelerated onset and progression of glomerulonephritis within 13 to 17 wk. Interestingly, dietary docosahexaenoic acid (DHA) supplementation suppresses these pathologic effects, but the underlying molecular mechanisms remain unclear. This study aimed to test the hypothesis that dietary DHA supplementation impacts acute transcriptional and autoantibody responses in the lungs of female NZBWF1 mice 1 and 4 wk after a single high-dose cSiO2 challenge. Groups of mice were initially fed a control (Con) diet or a DHA-containing diet (10 g/kg). Cohorts of Con- and DHA-fed were subjected to a single intranasal instillation of 2.5 mg cSiO2 in a saline vehicle (Veh), while a Con-fed cohort was instilled with Veh only. At 1 and 4 wk post-instillation (PI), we compared cSiO2's effects on innate-/autoimmune-related gene expression and autoantibody (AAb) in lavage fluid/lungs of Con- and DHA-fed mice and related these findings to inflammatory cell profiles, histopathology, cell death, and cytokine/chemokine production. DHA partially alleviated cSiO2-induced alterations in total immune cell and lymphocyte counts in lung lavage fluid. cSiO2-triggered dead cell accumulation and levels of inflammation-associated cytokines and IFN-stimulated chemokines were more pronounced in Con-fed mice than DHA-fed mice. Targeted multiplex transcriptome analysis revealed substantial upregulation of genes associated with autoimmune pathways in Con-fed mice in response to cSiO2 that were suppressed in DHA-fed mice. Pathway analysis indicated that DHA inhibited cSiO2 induction of proinflammatory and IFN-regulated gene networks, affecting key upstream regulators (e.g., TNFα, IL-1β, IFNAR, and IFNγ). Finally, cSiO2-triggered AAb responses were suppressed in DHA-fed mice. Taken together, DHA mitigated cSiO2-induced upregulation of pathways associated with proinflammatory and IFN-regulated gene responses within 1 wk and reduced AAb responses by 4 wk. These findings suggest that the acute short-term model employed here holds substantial promise for efficient elucidation of the molecular mechanisms through which omega-3 PUFAs exert protective effects against cSiO2-induced autoimmunity.

Chronic urticaria as a manifestation of multicentric Castleman disease treated with rituximab

AbstractWe present the case of a 26‐year‐old female with chronic urticaria (CU) with systemic symptoms in whom comprehensive laboratory and imaging studies led to the diagnosis of idiopathic multicentric Castleman disease. Treatment with rituximab induced resolution of CU. The association between these two entities is rare, and common autoimmune and autoinflammatory pathways may be involved in their production. Our case also emphasized the association of CU with an underlying systemic disease.

Emerging therapies in the medical management of thyroid eye disease.

Thyroid eye disease (TED) is an immune-mediated disorder associated with a heterogenous array of manifestations that may unfavorably impact vision and quality of life. As understanding of this entity's complex pathogenesis has evolved, so have therapies with novel molecular targets offering promise for improved patient outcomes. Emerging immunologic therapies for the management of thyroid eye disease have diverse mechanisms of actions and routes of administration. Different conventional and biological immunosuppressive agents have been studied as mediators of the autoimmune and autoinflammatory pathways in thyroid eye disease. Teprotumumab - an anti-IGF-1R monoclonal antibody that has recently emerged as a first-line therapy for active, moderate-to-severe TED - has demonstrated statistically significant improvements in proptosis, diplopia, clinical activity score, and quality of life compared to placebo. Currently under investigation are several other agents, with varying administration modalities, that aim to inhibit IGF-1R: VRDN-001 (intravenous), VRDN-002 or VRDN-003 (subcutaneous), lonigutamab (subcutaneous), and linsitinib (oral). Tocilizumab, a monoclonal antibody of interleukin 6, has played a role in the management of multiple autoimmune and inflammatory conditions and may offer promise in TED. Another incipient biologic target for TED management is the neonatal Fc receptor, inhibition of which has potential to decrease recycling of immunoglobulin and antibody levels; agents addressing this target including monoclonal antibodies as well as antibody fragments. Finally, hypolipidemic agents may play a role as mediators of TED-associated inflammation. Among the agents under investigation that aim to decrease ocular morbidity associated with TED are agents that IGF-1R, interleukin 6, and the neonatal Fc receptor. The management of TED continues to expand with novel immunologic approaches for disease therapy.

Egr2 Deletion in Autoimmune-Prone C57BL6/lpr Mice Suppresses the Expression of Methylation-Sensitive Dlk1-Dio3 Cluster MicroRNAs.

We previously demonstrated that the upregulation of microRNAs (miRNAs) at the genomic imprinted Dlk1-Dio3 locus in murine lupus is correlated with global DNA hypomethylation. We now report that the Dlk1-Dio3 genomic region in CD4+ T cells of MRL/lpr mice is hypomethylated, linking it to increased Dlk1-Dio3 miRNA expression. We evaluated the gene expression of methylating enzymes, DNA methyltransferases (DNMTs), and demethylating ten-eleven translocation proteins (TETs) to elucidate the molecular basis of DNA hypomethylation in lupus CD4+ T cells. There was a significantly elevated expression of Dnmt1 and Dnmt3b, as well as Tet1 and Tet2, in CD4+ T cells of three different lupus-prone mouse strains compared to controls. These findings suggest that the hypomethylation of murine lupus CD4+ T cells is likely attributed to a TET-mediated active demethylation pathway. Moreover, we found that deletion of early growth response 2 (Egr2), a transcription factor gene in B6/lpr mice markedly reduced maternally expressed miRNA genes but not paternally expressed protein-coding genes at the Dlk1-Dio3 locus in CD4+ T cells. EGR2 has been shown to induce DNA demethylation by recruiting TETs. Surprisingly, we found that deleting Egr2 in B6/lpr mice induced more hypomethylated differentially methylated regions at either the whole-genome level or the Dlk1-Dio3 locus in CD4+ T cells. Although the role of methylation in EGR2-mediated regulation of Dlk1-Dio3 miRNAs is not readily apparent, these are the first data to show that in lupus, Egr2 regulates Dlk1-Dio3 miRNAs, which target major signaling pathways in autoimmunity. These data provide a new perspective on the role of upregulated EGR2 in lupus pathogenesis.

THU354 Enfortumab Vedotin Induced Refractory Hyperglycemia

Abstract Disclosure: M. Hussein: None. Introduction: Immunotherapy has transformed the treatment landscape of cancer therapy and has created promising hope for cancer patients. While immunotherapy has dramatic efficacy it also has unique toxicity profile. A spectrum of adverse events known as endocrinopathies have been reported with immune checkpoint inhibitors. One of the newer medications is Enfortumab Vedotin, an antibody-drug conjugate. This drug is approved for use in advanced urothelial carcinoma. Case: We present a 68-year-old male with advanced urothelial carcinoma who was started on Enfortumab vedotin after he progressed on a different chemotherapy/immunotherapy. His medical history was significant for prediabetes and morbid obesity.2 weeks after the first cycle of treatment he presented to emergency room with worsening dyspnea and fatigue. Vital signs: Temp: 37.3, HR: 90, BP: 122/65, RR 18, SPO2 95% on 3L O2 through nasal canula. BMI 44 kg/m. Biochemical workup revealed elevated Glucose level of 310 and anion gap of 12. He was started on subcutaneous insulin. He continued to be uncontrolled and was transferred to the ICU and switched to intravenous insulin due to hyperglycemia. His total daily insulin dose was close to 900 units to achieve blood glucose &amp;lt;180. It took 48-72 hours of Intravenous insulin use to get controlled blood glucose. Hgba1c was 7.3%. Insulin antibody, GAD65 and Islet cell antibodies were negative, C peptide 38 for a glucose of 428. Unfortunately, the patient developed multiorgan failure, and passed away on day 7 of the admission. Discussion: The mechanism of this drug inducing hyperglycemia is not well understood as of yet. But the presumed theory here is the patient developed severe acute insulin resistance that led to this refractory hyperglycemia, as evident by the high c peptide level. Absence of beta cell antibodies and elevated c peptide go against an autoimmune destructive beta cell pathway. The other theory is that there is a malfunction in the signaling pathway at the cellular level that led to hyperglycemia. Risk of developing hyperglycemia as a side effect to this medication increase with patient’s personal risk factors for developing diabetes mellitus (prediabetes and obesity). In phase 3 trial of Enfortumab vedotinEV301, treatment related hyperglycemia was reported in 6.4 % of patients. Hyperglycemia occurred more frequently in patients with hyperglycemia at baseline or with a body-mass index of 30 or higher. Conclusion: We are in need for further studies to understand the mechanism of refractory hyperglycemia induced by this drug. Patients on this type of therapy should be monitored very closely for developing a new onset of diabetes mellitus or worsening of established diabetes mellitus. Presentation: Thursday, June 15, 2023

SAT065 Developmental Programming: Sex-specific Programming Of Pancreas In A Sheep Model Of Polycystic Ovary Syndrome

Abstract Disclosure: K.M. Halloran: None. A.K. Vyas: None. N. Saadat: None. V. Padmanabhan: None. Prenatal testosterone (T) treatment from gestational days (GD) 30-90 (sexually dimorphic window of fetal development where male fetuses naturally see elevated T) leads to reproductive and metabolic disruptions in female sheep that includes dyslipidemia, insulin resistance, and compensatory hyperinsulinemia similar to that seen in women with PCOS. The effects of excess T are seen as decreased pancreatic/fetal weight in female fetuses as opposed to an increase in beta cell size and lipid/collagen accumulation in adult females. We addressed the prenatal T-induced gene expression changes contributing to pancreatic compromise to determine if 1) the programmed event persists after cessation of T treatment, 2) T females (TF) are similar to control males (CM), and 3) it is exacerbated in the T males (TM). Time-mated pregnant sheep were administered T propionate (100 mg in 2 ml corn oil) or vehicle between GD 30-90 to obtain control female (CF), TF, CM, and TM fetuses (n=6/group). On ∼GD 120 (term: 147), fetuses were weighed and pancreas was collected, weighed, and the tail portion stored at -80°C until next-generation sequencing for gene expression profiling to identify potential pathways influenced by T and fetal sex. After removal of outliers (determined by Principal Component Analysis-PCA using SIMCA), 3D PCA plots showed clear separation of the treatment groups after stratifying by fetal sex. DESeq2 R package was used to identify differentially expressed genes (DEGs) between the comparisons of interest (CF vs TF, TF vs CM, and CM vs TM). Overall, T fetuses weighed less (P&amp;lt;0.05). Cohen’s effect size analysis found a large magnitude (Cohen’s d&amp;gt;0.8) decrease in fetal weight for TF vs CF, TM vs CM, and TF vs CM and a medium magnitude (d=0.5) decrease in pancreas weight for TF vs CM. Pancreatic:fetal weight ratios did not differ by treatment or fetal sex. 16 DEGS (1 up, 15 down) were identified between TF and CF, 7 DEGs (2 up, 4 down) between TF and CM, and 2 DEGs (up) between TM and CM (Adj P&amp;lt;0.1) with no overlap amongst them, suggesting that the effect of T in females is distinct from males and that TF are more similar to CM. Preliminary analysis indicates that the majority of the DEGs affected in TF are related to immune-signaling pathways, including c-type lectin domain family 4 member G (CLEC4G), cluster of differentiation 52 (CD52), and interleukin 21 receptor (IL21R); CD52, IL21R, and members of the CLEC4 family are implicated in autoimmune pathways linked to Type 1 diabetes. The 2 DEGs affected in TM are involved in plasma membrane dynamics: fer-1 like family member 6 (FER1L6) and chloride voltage gated channel 2 (CLCN2). These changes evident at the gene expression level a month after the cessation of T treatment is suggestive of sexually dimorphic reprogramming of fetal pancreas by exposure to excess T. Further, the endogenous increases in T seen in males may at least in part be responsible for sexually dimorphic programming. Presentation: Saturday, June 17, 2023

A new, all-encompassing aetiology of type 1 diabetes.

The aetiology of type 1 diabetes (T1D) is considered multifactorial with the contribution of the MHC on chromosome 6 being most important. Multiple factors also contribute to the aetiology of colorectal neoplasia, but the final event causing the change from normal mucosa to polyp and from polyp to cancer is due to a single somatic mutation event. Repeated formation of colorectal neoplasia within an at-risk population results in a predictable, tapering, exponential neoplasia distribution. Critical mutations driving colorectal neoplasia formation occur in mutation-prone DNA. These observations led to three hypotheses related to T1D. First, a single somatic mutation within the MHC of antigen presenting cells results in a change in phenotype from normal to T1D. Second, the distribution of additional autoimmune diseases (AAIDs) among persons with T1D adheres to a predictable, tapering, exponential distribution. And third, critical mutations driving development of T1D occur in mutation-prone DNA. To address the hypotheses in an orderly fashion, a new analytical method called genome-wide aetiology analysis (GWEA) consisting of nine steps is presented. All data required for GWEA of T1D are obtained from peer-reviewed publications or publicly available genome and proteome databases. Critical GWEA steps include AAID distribution among persons with T1D, analysis of at-risk HLA loci for mutation-prone DNA, determination of the role of non-MHC genes on GWAS, and verification of human data by cell culture or animal experiments. GWEA results show that distribution of AAID among persons with T1D adheres to a predictable, tapering, exponential distribution. A single, critical, somatic mutation within the epitope-binding groove of at-risk HLA loci alters HLA-insulin-peptide-T-cell-receptor (TCR) complex binding affinity and creates a new pathway that leads to loss of self-tolerance. The at-risk HLA loci, in particular binding pockets P1, P4 and P9, are encoded by mutation-prone DNA: GC-rich DNA sequence and somatic hypermutation hotspots. All other genes on GWAS can but do not have to amplify the new autoimmune pathway by facilitating DNA mutations, changing peptide binding affinity, reducing signal inhibition or augmenting signal intensity. Animal experiments agree with human studies. In conclusion, T1D is caused by a somatic mutation within the epitope-binding groove of an at-risk HLA gene that affects HLA-insulin-peptide-TCR complex binding affinity and initiates an autoimmune pathway. The nature of the peptide that binds to a mutated epitope-binding groove of an at-risk HLA gene determines the type of autoimmune disease that develops, that is, one at-risk HLA locus, multiple autoimmune diseases. Thus, T1D and AAIDs, and therefore common autoimmune diseases, share a similar somatic mutation-based aetiology.