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The gastrointestinal (GI) tract may be involved in systemic autoimmune diseases or may be the target of organ-specific autoimmunity. Autoimmune enteropathy (AIE) is a rare disorder characterized by severe and protracted diarrhea, weight loss from malabsorption and immune-mediated damage to the intestinal mucosa, generally occurring in infants and young children, only rarely in adult. The salient histopathologic features of AIE are most prominent in the small intestine: villous blunting, crypt hyperplasia, mononuclear cell inflammatory expansion of the lamina propria with intraepithelial lymphocytosis, crypt apoptosis and absence of Paneth cells, goblet cells or both. Esophagus, stomach and colon are frequently also involved. Anti-enterocyte antibodies are identified in the majority of cases, and their presence, even if variable, can help confirming the diagnosis. The purpose of this review is to provide an overview of the latest immunological advances in AIE, as well as to offer a practical approach for histological diagnosis for 'general' pathologist.

Background SARS-CoV-2 vaccination is recommended in patients with inborn errors of immunity (IEIs); however, little is known about immunogenicity and safety in these patients. Objective We sought to evaluate the impact of genetic diagnosis, age, and treatment on antibody response to COVID-19 vaccine and related adverse events in a cohort of patients with IEIs. Methods Plasma was collected from 22 health care worker controls, 81 patients with IEIs, and 2 patients with thymoma; the plasma was collected before immunization, 1 to 6 days before the second dose of mRNA vaccine, and at a median of 30 days after completion of the immunization schedule with either mRNA vaccine or a single dose of Johnson & Johnson’s Janssen vaccine. Anti-spike (anti-S) and anti-nucleocapsid antibody titers were measured by using a luciferase immunoprecipitation systems method. Information on T- and B-cell counts and use of immunosuppressive drugs was extracted from medical records, and information on vaccine-associated adverse events was collected after each dose. Results Anti-S antibodies were detected in 27 of 46 patients (58.7%) after 1 dose of mRNA vaccine and in 63 of 74 fully immunized patients (85.1%). A lower rate of seroconversion (7 of 11 [63.6%]) was observed in patients with autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy. Previous use of rituximab and baseline counts of less than 1000 CD3+ T cells/mL and less than 100 CD19+ B cells/mL were associated with lower anti-S IgG levels. No significant adverse events were reported. Conclusion Vaccinating patients with IEIs is safe, but immunogenicity is affected by certain therapies and gene defects. These data may guide the counseling of patients with IEIs regarding prevention of SARS-CoV-2 infection and the need for subsequent boosts.

Immune checkpoint inhibitor (ICI) therapies are now first-line therapy for many advanced malignancies in adults, with emerging use in children. With increasing ICI use, prompt recognition and optimal management of ICI-associated immune-related adverse events (IRAEs) are critical. Nearly 60% of ICI-treated adults develop IRAEs, which commonly manifest as autoimmune skin, gastrointestinal, and endocrine disease and can be life-threatening. The incidence, presentation, and disease course of spontaneous autoimmune diseases differ between adults and children, but the pattern of pediatric IRAEs is currently unclear. We report a case of a pediatric patient presenting with new onset autoimmune diabetes mellitus and diabetic ketoacidosis during ICI treatment of fibrolamellar hepatocellular carcinoma (FLC). Distinct from spontaneous type 1 diabetes mellitus (T1DM), this patient progressed rapidly and was negative for known β cell autoantibodies. Additionally, the patient was positive for 21-hydroxylase autoantibodies, suggesting development of concomitant adrenal autoimmunity. Current guidelines for the management of IRAEs in adults may not be appropriate for the management of pediatric patients, who may have different autoimmune risks in a developmental context.

Significance GBS and CIDP are autoimmune disorders of the PNS that can be debilitating and even life threatening. Current therapies, which include corticosteroids and intravenous gammaglobulin, have poorly defined mechanisms of action and are ineffective in a fraction of patients. To identify more specific therapeutic targets, we used single-cell RNA sequencing to analyze immune cells in nerves during autoimmune attack. This analysis revealed a previously unappreciated TNFα cell–cell communication pathway that recruits and activates multiple immune cell types. Moreover, we show that TNF-α signaling is an essential feature of PNS autoimmunity, since ablating TNF-α signaling protects against disease. These findings suggest that anti–TNF-α agents, which are already used to treat other inflammatory diseases, should be considered for inflammatory neuropathies., Immune cells infiltrate the peripheral nervous system (PNS) after injury and with autoimmunity, but their net effect is divergent. After injury, immune cells are reparative, while in inflammatory neuropathies (e.g., Guillain Barré Syndrome and chronic inflammatory demyelinating polyneuropathy), immune cells are proinflammatory and promote autoimmune demyelination. An understanding of immune cell phenotypes that distinguish these conditions may, therefore, reveal new therapeutic targets for switching immune cells from an inflammatory role to a reparative state. In an autoimmune regulator (Aire)-deficient mouse model of inflammatory neuropathy, we used single-cell RNA sequencing of sciatic nerves to discover a transcriptionally heterogeneous cellular landscape, including multiple myeloid, innate lymphoid, and lymphoid cell types. Analysis of cell–cell ligand–receptor interactions uncovered a macrophage-mediated tumor necrosis factor-α (TNF-α) signaling axis that is induced by interferon-γ and required for initiation of autoimmune demyelination. Developmental trajectory visualization suggested that TNF-α signaling is associated with metabolic reprogramming of macrophages and polarization of macrophages from a reparative state in injury to a pathogenic, inflammatory state in autoimmunity. Autocrine TNF-α signaling induced macrophage expression of multiple genes (Clec4e, Marcksl1, Cxcl1, and Cxcl10) important in immune cell activation and recruitment. Genetic and antibody-based blockade of TNF-α/TNF-α signaling ameliorated clinical neuropathy, peripheral nerve infiltration, and demyelination, which provides preclinical evidence that the TNF-α axis may be effectively targeted to resolve inflammatory neuropathies.

Patients with autoimmune polyendocrine syndrome type-1 (APS-1) have circulating auto-Abs neutralizing most type I interferons. These auto-Abs can underlie life-threatening COVID-19 pneumonia in the general population. The authors report 22 APS-1 patients infected with SARS-CoV-2, including 15 (68%) who developed life-threatening disease., Patients with biallelic loss-of-function variants of AIRE suffer from autoimmune polyendocrine syndrome type-1 (APS-1) and produce a broad range of autoantibodies (auto-Abs), including circulating auto-Abs neutralizing most type I interferons (IFNs). These auto-Abs were recently reported to account for at least 10% of cases of life-threatening COVID-19 pneumonia in the general population. We report 22 APS-1 patients from 21 kindreds in seven countries, aged between 8 and 48 yr and infected with SARS-CoV-2 since February 2020. The 21 patients tested had auto-Abs neutralizing IFN-α subtypes and/or IFN-ω; one had anti–IFN-β and another anti–IFN-ε, but none had anti–IFN-κ. Strikingly, 19 patients (86%) were hospitalized for COVID-19 pneumonia, including 15 (68%) admitted to an intensive care unit, 11 (50%) who required mechanical ventilation, and four (18%) who died. Ambulatory disease in three patients (14%) was possibly accounted for by prior or early specific interventions. Preexisting auto-Abs neutralizing type I IFNs in APS-1 patients confer a very high risk of life-threatening COVID-19 pneumonia at any age.

Autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy (APECED), caused by mutations in the AIRE gene, is mainly characterized by the triad of hypoparathyroidism, primary adrenocortical insufficiency and chronic mucocutaneous candidiasis, but can include many other manifestations, with no currently clear genotype–phenotype correlation. We present the clinical features of two siblings, a male and a female, with the same mutations in the AIRE gene associated with two very different phenotypes. Interestingly, the brother recently experienced COVID-19 infection with pneumonia, complicated by hypertension, hypokalemia and hypercalcemia. Although APECED is a monogenic disease, its expressiveness can be extremely different. In addition to the genetic basis, epigenetic and environmental factors might influence the phenotypic expression, although their exact role remains to be elucidated.

INTRODUCTION: Studies of monogenic diseases have uncovered the importance of immune pathways in human tissue-specific immunity and antimicrobial defense. In particular, human inborn errors of the interleukin-17 (IL-17) receptor signaling pathway and corroborating mouse studies have established the critical contribution of type 17 responses inmucosa-specific fungal surveillance. The yeast Candida albicans is the signature pathogen in autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy (APECED), an inherited autoimmune disease caused by loss-of-function mutations in the autoimmune regulator (AIRE) gene. Fungal disease in APECED is limited to chronic mucocutaneous candidiasis (CMC) without dissemination, suggesting a central defect in barrier immunity. RATIONALE: AIRE deficiency impairs central immune tolerance, resulting in the generation of pathogenic autoreactive T cells and autoantibodies directed against many tissue-specific antigens and certain cytokines, including “type 17” cytokines. However, although a majority of APECED patients with CMC have type 17 cytokine–targeted autoantibodies, whether type 17 or other localmucosal immune responses are affected in AIRE deficiency has not been determined. Here, we broadly investigated oral mucosal immune responses both in a model of oropharyngeal candidiasis in Aire(−/−) mice and in a large cohort of APECED patients. RESULTS: Type 17 immune responses at the oralmucosa were unexpectedly intact in mice and humans with AIRE deficiency. To define alternative mechanisms of fungal susceptibility, we investigated Aire(−/−) mice, which exhibited oralmucosa-specific susceptibility to candidiasis without dissemination and controlled experimental challenges with viruses and bacteria normally, thereby phenocopying the infection predisposition observed in APECED patients. Notably, Aire(−/−) CD4(+) and CD8(+) T cells accumulated in increased numbers and displayed an activated and proliferative phenotype within the oral mucosa and were both necessary and sufficient to drive mucosal fungal infection in Aire deficiency. Enhanced production of interferon-γ (IFN-γ) by Aire(−/−) mucosal CD4(+) and CD8(+) T cells resulted in exacerbated IFN-γ/STAT1-mediated responses in the oral mucosa, which promoted IFN-γ–dependent epithelial barrier disruption and mucosal fungal susceptibility. Genetic and pharmacologic inhibition of IFN-γ or JAK-STAT signaling ameliorated mucosal fungal disease in Aire(−/−) mice. Aberrant type 1 responseswere also observed in the oral mucosa of APECED patients. CONCLUSION: We identify a T cell–dependent interferonopathy as a critical local mucosal mechanism underlying CMC in APECED. Although type 17 mucosal immunity is critical for host defense against barrier infection, mucosal type 17 responses were intact in patients with APECED and in a mouse model of the disease. These findings show that, in contrast to the known protective roles of T cells in antifungal host defense, aberrant type 1–associated T cell responses can be detrimental to antifungal mucosal immunity. They also support a paradigm by which exaggerated immunopathology may facilitate susceptibility to mucosal fungal infection by impairing the integrity of the epithelial barrier. Finally, they pave the way for investigating type 1 mucosal responses in other CMC-manifesting diseases and for the prevention and treatment of CMC in APECED patients using FDA-approved therapies that target IFN-γ or JAK-STAT signaling.

Human monogenic disorders have revealed the critical contribution of type 17 responses in mucosal fungal surveillance. We unexpectedly found that in certain settings, enhanced type 1 immunity rather than defective type 17 responses can promote mucosal fungal infection susceptibility. Notably, in mice and humans with AIRE deficiency, an autoimmune disease characterized by selective susceptibility to mucosal but not systemic fungal infection, mucosal type 17 responses are intact while type 1 responses are exacerbated. These responses promote aberrant interferon-γ (IFN-γ)- and signal transducer and activator of transcription 1 (STAT1)-dependent epithelial barrier defects as well as mucosal fungal infection susceptibility. Concordantly, genetic and pharmacologic inhibition of IFN-γ or Janus kinase (JAK)-STAT signaling ameliorates mucosal fungal disease. Thus, we identify aberrant T cell-dependent, type 1 mucosal inflammation as a critical tissue-specific pathogenic mechanism that promotes mucosal fungal infection susceptibility in mice and humans.

AIRE is a well-established master regulator of central tolerance. It plays an essential role in driving expression of tissue-specific antigens in the thymus and shaping the development of positively selected T-cells. Humans and mice with compromised or absent AIRE function have markedly variable phenotypes that include a range of autoimmune manifestations. Recent evidence suggests that this variability stems from cooperation of autoimmune susceptibilities involving both central and peripheral tolerance checkpoints. Here we discuss the broadening understanding of the factors that influence Aire expression, modify AIRE function, and the impact and intersection of AIRE with peripheral immunity. This rapidly expanding body of knowledge will force a reexamination of the definition and clinical management of APS-1 patients as well as provide a foundation for the development of immunomodulatory strategies targeting central tolerance.

In 2016, we reported four substantial observations of APECED/APS1 patients, who are deficient in AIRE, a major regulator of central T cell tolerance (Meyer et al., 2016). Two of those observations have been challenged. Specifically, ‘private’ autoantibody reactivities shared by only a few patients but collectively targeting >1000 autoantigens have been attributed to false positives (Landegren, 2019). While acknowledging this risk, our study-design included follow-up validation, permitting us to adopt statistical approaches to also limit false negatives. Importantly, many such private specificities have now been validated by multiple, independent means including the autoantibodies’ molecular cloning and expression. Second, a significant correlation of antibody-mediated IFNα neutralization with an absence of disease in patients highly disposed to Type I diabetes has been challenged because of a claimed failure to replicate our findings (Landegren, 2019). However, flaws in design and implementation invalidate this challenge. Thus, our results present robust, insightful, independently validated depictions of APECED/APS1, that have spawned productive follow-up studies.

Regulatory T (Treg) cells maintain immune tolerance through the master transcription factor forkhead box P3 (FOXP3), which is crucial for Treg cell function and homeostasis. We identified an IPEX (immune dysregulation polyendocrinopathy enteropathy X-linked) syndrome patient with a FOXP3 mutation in the domain swap interface of the protein. Recapitulation of this Foxp3 variant in mice led to the development of an autoimmune syndrome consistent with an unrestrained T helper type 2 (Th2) immune response. Genomic analysis of Treg cells by RNA-sequencing, Foxp3 chromatin immunoprecipitation followed byhigh-throughput DNA sequencing (ChIP-sequencing), and H3K27ac-HiChIP revealed a specific de-repression of the Th2 transcriptional program leading to the generation of Th2-like Treg cells that were unable to suppress extrinsic Th2 cells. Th2-like Treg cells showed increased intra-chromosomal interactions in the Th2 locus, leading to type 2 cytokine production. These findings identify a direct role for Foxp3 in suppressing Th2-like Treg cells and implicate additional pathways that could be targeted to restrain Th2 trans-differentiated Treg cells.

We report a 23 year old woman presenting with a nephrotic syndrome due to minimal change disease, central diabetes insipidus, primary hypothyroidism, vitiligo and universal alopecia. Eleven years later, she presented secondary amenorrhea due to hypogonadotropic hypogonadism, with mild hyperprolactinemia and central adrenal insufficiency. A magnetic resonance imaging of the sella turcica showed a pituitary mass with suprasellar extension that was resected using a transsphenoidal approach. Pathology confirmed the presence of a lymphoplasmacytic hypophysitis. She needed a second surgical resection due to mass growth and neuro-ophthalmologic impairment. One year later, systemic lupus erythematosus, arterial hypertension and type 2 diabetes mellitus were diagnosed. Two years later, due to back pain, constipation and renal failure, retroperitoneal fibrosis was found, satisfactorily treated with glucocorticoids and colchicine. Hence, this clinical vignette shows the coexistence of autoimmune polyglandular syndrome with retroperitoneal fibrosis and lymphoplasmacytic hypophysitis. Tissue analysis showed the presence of IgG4 producing plasma cells in the pituitary and retroperitoneum, which constitute a basis for the diagnosis of IgG4 related disease.

We report a 23 year old woman presenting with a nephrotic syndrome due to minimal change disease, central diabetes insipidus, primary hypothyroidism, vitiligo and universal alopecia. Eleven years later, she presented secondary amenorrhea due to hypogonadotropic hypogonadism, with mild hyperprolactinemia and central adrenal insufficiency. A magnetic resonance imaging of the sella turcica showed a pituitary mass with suprasellar extension that was resected using a transsphenoidal approach. Pathology confirmed the presence of a lymphoplasmacytic hypophysitis. She needed a second surgical resection due to mass growth and neuro-ophthalmologic impairment. One year later, systemic lupus erythematosus, arterial hypertension and type 2 diabetes mellitus were diagnosed. Two years later, due to back pain, constipation and renal failure, retroperitoneal fibrosis was found, satisfactorily treated with glucocorticoids and colchicine. Hence, this clinical vignette shows the coexistence of autoimmune polyglandular syndrome with retroperitoneal fibrosis and lymphoplasmacytic hypophysitis. Tissue analysis showed the presence of IgG4 producing plasma cells in the pituitary and retroperitoneum, which constitute a basis for the diagnosis of IgG4 related disease.

More than 15 years ago, mutations in the autoimmune regulator (AIRE) gene were identified as the cause of autoimmune polyglandular syndrome type 1 (APS1). It is now clear that this transcription factor has a crucial role in promoting self-tolerance in the thymus by regulating the expression of a wide array of self-antigens that have the commonality of being tissue-restricted in their expression pattern in the periphery. In this Review, we highlight many of the recent advances in our understanding of the complex biology that is related to AIRE, with a particular focus on advances in genetics, molecular interactions and the effect of AIRE on thymic selection of regulatory T cells. Furthermore, we highlight new areas of biology that are potentially affected by this key regulator of immune tolerance.

Autoimmune polyendocrine syndrome type 1 (APS-1; OMIM #240300), also referred to as autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), is a rare monogenic autoimmune disorder caused by mutations in the autoimmune regulator (AIRE) gene. APS-1 is classically characterized by a triad of chronic mucocutaneous candidiasis, autoimmune hypoparathyroidism, and autoimmune adrenocortical insufficiency. We report a 5-yr-old female who presented with symptoms of tetany due to hypocalcemia and was subsequently found to be secondary to hypoparathyroidism. Rapid trio whole-genome sequencing revealed compound heterozygous variants in AIRE in the proband, with a paternally inherited, pathogenic, frameshift variant (c.1265delC; p.Pro422LeufsTer58) and a novel, likely pathogenic, maternally inherited missense variant (c.268T>C; p.Tyr90His).

Enteropathy-associated T-cell lymphoma is regarded as a dismal, late complication of coeliac disease, though a single case of T-cell lymphoma with such features arising in the setting of autoimmune enteropathy of the adult has been reported to date. We aim to describe the case of a 41-year-old woman complaining of severe malabsorption syndrome, who was diagnosed with autoimmune enteropathy based on the presence of flat intestinal mucosa unresponsive to any dietary restriction and positivity for enterocyte autoantibodies. Steroid therapy led to a complete recovery of both mucosal and clinical findings over 12 years, when disease relapse was accompanied by the appearance of monoclonal rearrangement of T-cell receptor-γ and peculiar T-cell phenotypic abnormalities, leading to a rapid transition to an overt T-cell lymphoma with features of the enteropathy-associated subtype. Despite intensive treatment, the patient developed cerebral metastasis and died 9 months later. Our case enhances the concept of enteropathy-associated T-cell lymphoma as a disease that may arise in the setting of enteropathies other than coeliac disease, thus representing a heterogeneous entity. Moreover, our observations support the need of a close follow-up of these patients, coupled with comprehensive characterization of mucosal biopsies.

Background: No reviews have specifically addressed, to now, whether autoimmune polyglandular syndromes (APSs) may have a peculiar epidemiology and phenotypical expression in pediatric age. Objectives: To review the most recent literature data about the specific epidemiological and clinical peculiarities of APSs in childhood and adolescence. Design: The main features of the different APSs in pediatric age were compared among them. Conclusions: 1) Among the different APSs, the one that is most typical of pediatric age is APS-1; 2) APS-1 is not characterized only by the classical triad (chronic moniliasis-hyposurrenalism-hypoparathyroidism) and its clinical spectrum is enlarging over time; 3)APS-2 may have a different epidemiological and clinical expression according to two different nosological classifications. (www.actabiomedica.it)

Background Data collected in EHRs have been widely used to identifying specific conditions; however there is still a need for methods to define comorbidities and sources to identify comorbidities burden. We propose an approach to assess comorbidities burden for a specific disease using the literature and EHR data sources in the case of autoimmune diseases in celiac disease (CD). Methods We generated a restricted set of comorbidities using the literature (via the MeSH® co-occurrence file). We extracted the 15 most co-occurring autoimmune diseases of the CD. We used mappings of the comorbidities to EHR terminologies: ICD-10 (billing codes), ATC (drugs) and UMLS (clinical reports). Finally, we extracted the concepts from the different data sources. We evaluated our approach using the correlation between prevalence estimates in our cohort and co-occurrence ranking in the literature. Results We retrieved the comorbidities for 741 patients with CD. 18.1% of patients had at least one of the 15 studied autoimmune disorders. Overall, 79.3% of the mapped concepts were detected only in text, 5.3% only in ICD codes and/or drugs prescriptions, and 15.4% could be found in both sources. Prevalence in our cohort were correlated with literature (Spearman’s coefficient 0.789, p = 0.0005). The three most prevalent comorbidities were thyroiditis 12.6% (95% CI 10.1–14.9), type 1 diabetes 2.3% (95% CI 1.2–3.4) and dermatitis herpetiformis 2.0% (95% CI 1.0–3.0). Conclusion We introduced a process that leveraged the MeSH terminology to identify relevant autoimmune comorbidities of the CD and several data sources from EHRs to phenotype a large population of CD patients. We achieved prevalence estimates comparable to the literature. Electronic supplementary material The online version of this article (10.1186/s12911-017-0537-y) contains supplementary material, which is available to authorized users.

Polyglandular autoimmune syndrome is defined as multiple endocrine gland insufficiencies accompanied by autoimmune diseases of the endocrine and nonendocrine system. After Schmidt introduced a case of nontuberculosis adrenal gland dysfunction with thyroiditis in 1926, Neufeld defined polyglandular autoimmune syndrome by I, II, and III subtypes in 1980 by their presentation of occurrence age, heredity methods, relationship with human leukocyte antigen, and accompanying diseases. We report a case of a 32-year-old female with polyglandular autoimmune syndrome III accompanied by type 1 diabetes mellitus that was treated with insulin (36 units per day) for 11 years. She had insulin deficiency and Hashimoto thyroiditis as an autoimmune disorder. In addition, she had several features similar to Albright's hereditary osteodystrophy including short stature, truncal obesity, round face, short neck, low intelligence (full IQ 84), and decreased memory. Although Albright's hereditary osteodystrophy is morphological evidence of pseudohypoparathyroidism or pseudopseudohypoparathyroidism, she had primary hypoparathyroidism on laboratory results. Here, we report a case of polyglandular autoimmune syndrome III with type 1 diabetes mellitus, autoimmune thyroiditis, and primary hypoparathyroidism, accompanied by clinical features similar to Albright's hereditary osteodystrophy.

Autoimmune polyendocrine syndrome type 1 (APS1) is a monogenic disorder that features multiple autoimmune disease manifestations. It is caused by mutations in the Autoimmune regulator (AIRE) gene, which promote thymic display of thousands of peripheral tissue antigens in a process critical for establishing central immune tolerance. We here used proteome arrays to perform a comprehensive study of autoimmune targets in APS1. Interrogation of established autoantigens revealed highly reliable detection of autoantibodies, and by exploring the full panel of more than 9000 proteins we further identified MAGEB2 and PDILT as novel major autoantigens in APS1. Our proteome-wide assessment revealed a marked enrichment for tissue-specific immune targets, mirroring AIRE's selectiveness for this category of genes. Our findings also suggest that only a very limited portion of the proteome becomes targeted by the immune system in APS1, which contrasts the broad defect of thymic presentation associated with AIRE-deficiency and raises novel questions what other factors are needed for break of tolerance.

Immune dysregulation, Polyendocrinopathy, Enteropathy X-linked (IPEX) syndrome is a unique example of primary immunodeficiency characterized by autoimmune manifestations due to defective regulatory T (Treg) cells, in the presence of FOXP3 mutations. However, autoimmune symptoms phenotypically resembling IPEX often occur in the absence of detectable FOXP3 mutations. The cause of this “IPEX-like” syndrome presently remains unclear. To investigate whether a defect in Treg cells sustains the immunological dysregulation in IPEX-like patients, we measured the amount of peripheral Treg cells within the CD3+ T cells by analysing demethylation of the Treg cell-Specific-Demethylated-Region (TSDR) in the FOXP3 locus and demethylation of the T cell-Specific-Demethylated-Region (TLSDR) in the CD3 locus, highly specific markers for stable Treg cells and overall T cells, respectively. TSDR demethylation analysis, alone or normalized for the total T cells, showed that the amount of peripheral Treg cells in a cohort of IPEX-like patients was significantly reduced, as compared to both healthy subjects and unrelated disease controls. This reduction could not be displayed by flow cytometric analysis, showing highly variable percentages of FOXP3+ and CD25+FOXP3+ T cells. These data provide evidence that a quantitative defect of Treg cells could be considered a common biological hallmark of IPEX-like syndrome. Since Treg cell suppressive function was not impaired, we propose that this reduction per se could sustain autoimmunity., Highlights ► FOXP3 (TSDR) and CD3 (TLSDR) demethylation assays allow Treg cell quantification. ► TSDR/TLSDR ratio is altered in the majority of patients with immune dysregulation. ► IPEX-like syndromes share a quantitative but not functional defect of Treg cells.

The autoimmune regulator (Aire) was initially identified as the gene causing multiorgan system autoimmunity in humans, and deletion of this gene in mice also resulted in organ-specific autoimmunity. Aire regulates the expression of tissue-specific antigens (TSAs) in medullary thymic epithelial cells (mTECs), which play a critical role in the negative selection of autoreactive T cells and the generation of regulatory T cells. More recently, the role of Aire in the development of mTECs has helped elucidate its ability to present the spectrum of TSAs needed to prevent autoimmunity. Molecular characterization of the functional domains of Aire has revealed multiple binding partners that assist Aire's function in altering gene transcription and chromatin remodeling. These recent advances have further highlighted the importance of Aire in central tolerance.

Autoantibodies to autoimmune enteropathy-related 75 kDa antigen (AIE-75) and villin are disease markers of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome which is characterized by a peripheral tolerance defect. On the other hand, anti-tryptophan hydroxylase-1 (TPH-1) antibodies are detected in autoimmune polyendocrinopathy, candidiasis, ectodermal dystrophy (APECED), a central tolerance defect, especially when complicated with gastrointestinal dysfunction. However, to date, anti-AIE-75 and anti-villin antibodies or anti-TPH-1 antibodies have not been tested in APECED or IPEX syndrome, respectively. In the present study, we confirmed the disease specificity of both anti-AIE-75 and anti-TPH-1, although anti-villin antibodies were detected in some patients with APECED. Our observation suggests that immunotolerance to AIE-75 depends on the peripheral mechanism, whereas the tolerance to TPH-1 depends on the central mechanisms.

Autoimmune polyendocrine syndromes (APS), also called polyglandular autoimmune syndromes (PGAS), are a heterogeneous group of rare diseases characterized by autoimmune activity against more than one endocrine organs, although non-endocrine organs can be affected. The two major autoimmune polyendocrine syndromes, (type1-type2/APS-1 and APS-2), both have Addison's disease as a prominent component. Further autoimmune polyendocrine syndromes include APS3 and APS4. The major autoimmune polyendocrine syndromes have a strong genetic component with the type 2 syndrome occurring in multiple generations and the type I syndrome in siblings. It is well recognized that more than 20years may elapse between the onset on one endocrinopathy and the diagnosis of the next, for example, almost 40-50% of subjects with Addison's disease will develop an associated endocrinopathy. The discovery of the polyendocrine autoimmune syndromes offered the possibility to understand autoimmune disorders with particular interest for type 1A diabetes and the neuroendocrine immunology (NEI) is further contributing to understand the links.

Autoantibodies against cytokines, chemokines, and growth factors inhibit normal immunity and are implicated in inflammatory autoimmune disease and diseases of immune deficiency. In an effort to evaluate serum from autoimmune and immunodeficient patients for Abs against cytokines, chemokines, and growth factors in a high-throughput and unbiased manner, we constructed a multiplex protein microarray for detection of serum factor-binding Abs and used the microarray to detect autoantibody targets in SLE. We designed a nitrocellulose-surface microarray containing human cytokines, chemokines, and other circulating proteins and demonstrated that the array permitted specific detection of serum factor-binding probes. We used the arrays to detect previously described autoantibodies against cytokines in samples from individuals with autoimmune polyendocrine syndrome type 1 and chronic mycobacterial infection. Serum profiling from individuals with SLE revealed that among several targets, elevated IgG autoantibody reactivity to B cell-activating factor (BAFF) was associated with SLE compared with control samples. BAFF reactivity correlated with the severity of disease-associated features, including IFN-α-driven SLE pathology. Our results showed that serum factor protein microarrays facilitate detection of autoantibody reactivity to serum factors in human samples and that BAFF-reactive autoantibodies may be associated with an elevated inflammatory disease state within the spectrum of SLE.

Interstitial lung disease (ILD) is a complex and heterogeneous disorder that is often associated with autoimmune syndromes. Despite the connection between ILD and autoimmunity, it remains unclear whether ILD can develop from an autoimmune response that specifically targets the lung parenchyma. We examined a severe form of autoimmune disease, autoimmune polyglandular syndrome type 1 (APS1), and established a strong link between an autoimmune response to the lung-specific protein BPIFB1 (bactericidal/permeability-increasing fold-containing B1) and clinical ILD. Screening of a large cohort of APS1 patients revealed autoantibodies to BPIFB1 in 9.6% of APS1 subjects overall and in 100% of APS1 subjects with ILD. Further investigation of ILD outside the APS1 disorder revealed BPIFB1 autoantibodies present in 14.6% of patients with connective tissue disease-associated ILD and in 12.0% of patients with idiopathic ILD. The animal model for APS1, Aire⁻/⁻ mice, harbors autoantibodies to a similar lung antigen (BPIFB9); these autoantibodies are a marker for ILD. We found that a defect in thymic tolerance was responsible for the production of BPIFB9 autoantibodies and the development of ILD. We also found that immunoreactivity targeting BPIFB1 independent of a defect in Aire also led to ILD, consistent with our discovery of BPIFB1 autoantibodies in non-APS1 patients. Overall, our results demonstrate that autoimmunity targeting the lung-specific antigen BPIFB1 may contribute to the pathogenesis of ILD in patients with APS1 and in subsets of patients with non-APS1 ILD, demonstrating the role of lung-specific autoimmunity in the genesis of ILD.

El síndrome poliglandular autoinmune es un desorden inmunológico que afecta diferentes glándulas endocrinas y que se asocia frecuentemente a enfermedades cutáneas de origen autoinmune como el vitiligo. Actualmente se clasifica en tres grupos de acuerdo a las glándulas comprometidas. El síndrome poliglandular autoinmune tipo IIIB es el más comúnmente reportado y se caracteriza por enfermedad tiroidea autoinmune con gastritis autoinmune. Aunque hay asociación con alopecia areata, es el vitiligo la enfermedad cutánea que más se asocia con este síndrome. Se presenta el caso de una paciente de 50 años con síndrome poliglandular autoinmune tipo IIIB, quien presentó inicialmente una tiroiditis autoinmune, posteriormente fue diagnosticada con anemia perniciosa secundaria a deficiencia de vitamina B12 y finalmente un vitiligo generalizado, resistente a múltiples tratamientos, a pesar del control de sus endocrinopatías. Autoimmune poliglandular syndrome is an immune disorder, that affects different endocrine glands and that is frequently associated with cutaneous disorders of autoinmune etiology like vitiligo. It is currently classified in three groups depending on the compromised gland. Type IIIB autoimmune polyglandular syndrome is the most frequently reported and is characterized by autoimmune thyroid disease with autoimmune gastritis. Although, it is also associated wih alopecia areata, vitiligo is the most frequently cutaneous disease reported in this syndrome. We report a 50 year old woman with a type IIIB autoimmune poliglandular síndrome who had an autoimmune thyroid disease with hyperthyroidism 25 years before, later she was diagnosed with pernicious anemia secondary to vitamin B12 deficiency and finally presented a generalized vitiligo, resistant to multiple treatments des-pite good control of her autoimmune illnesses.

Purpose of reviewAdvances in human genetics and investigations in animal models of autoimmune disease have allowed insight into the basic mechanisms of immunologic tolerance. These advances allow us to understand the pathogenesis of type 1 diabetes and other autoimmune diseases as never before. Here, we discuss the tolerance mechanisms of the autoimmune polyendocrine syndromes and their relevance to type 1 diabetes.Recent findingsDefects in central tolerance with alteration of self-antigen expression levels in the thymus are a potent cause of autoimmunity. Peripheral tolerance defects that alter T-cell activation and signaling also play an important role in the pathogenesis of diabetes and other associated autoimmune disorders, with multiple modest defects working in concert to produce disease. Regulation of the immune response through the action of regulatory T cells is a potent mode of tolerance induction in autoimmunity that is important in type 1 diabetes.SummaryRare syndromes of autoimmunity provide a valuable window into the breakdown of tolerance and identify multiple checkpoints that are critical for generation of autoimmunity. Understanding the application of these in type 1 diabetes will allow the development of future immunomodulatory therapies in the treatment and prevention of disease.

Objective: Type 1 diabetes (T1D) iscommonlyassociated withautoimmunethyroid disease (AITD),and the occurrence of both T1D and AITD in a patient is defined as autoimmune polyglandular syndrome type 3 variant (APS3v). We aimed to clarify the differences in the clinical and genetic characteristics of APS3v patients and T1D patients without AITD [T1D/AITD(-)] in the Japanese population. Design/Patients: Our subjects were 54 APS3v patients and 143 T1D/AITD(-) patients who were consecutively diagnosed at Nagasaki University Hospital from 1983 to the present. Results: A remarkable female predominance, a slow and older age onset of T1D, and a higher prevalence of glutamic acid decarboxylase autoantibodies were observed in APS3v patients compared to T1D/AITD(-) patients. The older onset age of T1D in APS3v patients was associated with a higher proportion of slow-onset T1D. Among the two major susceptible human leukocyte antigen (HLA) class II haplotypes in Japanese T1D, DRB1*0405- DQB1*0401, but not DRB1*0901-DQB1*0303, was associated with APS3v patients. Furthermore, DRB1*0803-DQB1*0601 was not protective in patients with APS3v. The frequencies of the GG genotype in +49G>A and +6230G>A polymorphism in the CTLA4 gene were significantly higher in T1D/AITD(-) patients, but not in APS3v patients, compared to control subjects. Conclusions: In conclusion, we found notable differences in the clinical and genetic characteristics of APS3v patients and T1D/AITD(-) patients in the Japanese population, and the differences in the clinical characteristics between the two groups may reflect distinct genetic backgrounds including the HLA DRB1-DQB1 haplotypes and CTLA4 gene polymorphisms., Journal of Clinical Endocrinology & Metabolism, 97(6), pp.E1043-E1050; 2012

Adult autoimmune enteropathy (AIE) is a rare cause of malabsorption syndrome unresponsive to dietary restriction. Its diagnostic hallmarks are small-bowel villous atrophy and antienterocyte autoantibodies. Therapy is based mainly on nutritional support and immunosuppression. We treated a 61-year-old woman with corticosteroid-refractory AIE and life-threatening malabsorption syndrome with systemic infusions of autologous, bone marrow-derived, mesenchymal stromal cells (MSCs) as rescue therapy. The MSCs were expanded ex vivo following a previously used Good Manufacturing Practice procedure, and 2 intravenous infusions of 1.8 × 106 MSCs/kg body weight were administered 2 weeks apart. Analysis of circulating and mucosal regulatory T-and B-cell numbers, and of serum and secretory immunoglobulin levels, was performed before and after treatment. The MSC infusions were safe and effective, leading to disappearance of disease hallmarks and recovery from the life-threatening condition. Increases in mucosal regulatory T-cell numbers and secretory immunoglobulin levels were also observed. The benefit, however, was transient, and a further MSC infusion resulted in the same short efficacy. This case encourages the use of MSCs to treat patients with lifethreatening, corticosteroid-refractory AIE and suggests that MSC infusion can attenuate, albeit transiently, the autoimmune attack. © 2012 Mayo Foundation for Medical Education and Research.

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Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is a rare autosomal recessive organ-specific autoimmune disorder that is characterized by a variable combination of (i) chronic mucocutaneous candidiasis, (ii) polyendocrinopathy and/or hepatitis and (iii) dystrophy of the dental enamel and nails. We analyzed the AIRE (autoimmune regulator) gene in subjects who presented any symptom that has been associated with APECED, including candidiasis and autoimmune endocrinopathy. We observed that 83.3% of patients presented at least two of the three typical manifestations of APECED, while the remaining 16.7% of patients showed other signs of the disease. Analysis of the genetic diagnosis of these subjects revealed that a considerable delay occurs in the majority of patients between the appearance of symptoms and the diagnosis. Overall, the mean diagnostic delay in our patients was 10.2 years. These results suggest that molecular analysis of AIRE should be performed in patients with relapsing mucocutaneous candidiasis for early identification of APECED. Fondazione Cariplo Fondazione Telethon European Commission (FP7 HLH-cure) (201461) Ministry of Education, Universities and Research (MIUR) Research Projects of National Relevance (PRIN) (2007ACZMMZ_005) Seventh Framework Programme (201461)

We report a 12-year-old patient with growth retardation, exercise intolerance, lactic acidosis (increasing after exercise) and autoimmune polyendocrinopathy type 2. Muscle biopsy shows abundant COX-negative fibers, subsarcolemmal mitochondrial aggregates and markedly reduced activities of all respiratory chain complexes. Genetic analysis identified two new cosegregating mutations in Met-tRNA (m.4415A>G) and Cox III (m.9922A>C), located in highly conserved regions of MtDNA. Both the mutations are heteroplasmics in multiple patients' tissues. Single-muscle fiber analysis showed significantly higher levels of both the mutations in COX-negative than in normal fibers. In addition, a possible link between the mitochondrial dysfunction and the autoimmune disease is suggested.

BACKGROUND: Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is an autoimmune genetic disorder caused by mutation of the forkhead box protein 3 gene (FOXP3), a key regulator of immune tolerance. OBJECTIVE: We sought to provide clinical and molecular indicators that facilitate the understanding and diagnosis of IPEX syndrome. METHODS: In 14 unrelated affected male subjects who were given diagnoses of IPEX syndrome based on FOXP3 gene sequencing, we determined whether particular FOXP3 mutations affected FOXP3 protein expression and correlated the molecular and clinical data. RESULTS: Molecular analysis of FOXP3 in the 14 subjects revealed 13 missense and splice-site mutations, including 7 novel mutations. Enteropathy, generally associated with endocrinopathy and eczema, was reported in all patients, particularly in those carrying mutations within FOXP3 functional domains or mutations that altered protein expression. However, similar genotypes did not always result in similar phenotypes in terms of disease presentation and severity. In addition, FOXP3 protein expression did not correlate with disease severity. CONCLUSION: Severe autoimmune enteropathy, which is often associated with increased IgE levels and eosinophilia, is the most prominent early manifestation of IPEX syndrome. Nevertheless, the disease course is variable and somewhat unpredictable. Therefore genetic analysis of FOXP3 should always be performed to ensure an accurate diagnosis, and FOXP3 protein expression analysis should not be the only diagnostic tool for IPEX syndrome. OI RONCAROLO, Maria Grazia/0000-0002-2193-9186 ZS 1 ZR 2 ZB 47 Z8 7

Autoantibodies to adenohypophyseal endocrine cells or to vasopressin neurohypophyseal neurons have long been known. Conversely, autoimmune targeting of further hypothalamic-hypophyseal structures, such as the blood-brain barrier-deprived median eminence, has been little studied.We studied a case of autoimmune polyendocrine syndrome type I with GH secretory deficiency, a distinctly rare event in autoimmune polyendocrine syndrome type I. We used rat and bovine tissue substrates to study autoantibodies against hypothalamic-hypophyseal nerve structures and endocrine cells.In the study case, circulating autoantibodies selectively decorated median eminence dopaminergic nerve terminals, as well as pituitary gonadotropes, but not GHRH nerve terminals or pituitary somatotropes. Such autoantibodies appeared de novo in parallel with the onset of GH secretory deficiency, whereas no median eminence labeling was found in patients suffering of idiopathic GH deficiency (n = 7) or in healthy controls (n = 23).The pathophysiological significance of our patient's autoantibodies remains to be confirmed. Nonetheless, the heterogeneous neuroendocrine structures of the median eminence are pointed out as potential immune targets, relevant to autoimmune polyendocrinopathy, as well as to a wide range of other conditions.

Background Mutations in signal transducer and activator of transcription (STAT) 1 cause a broad spectrum of disease, ranging from severe viral and bacterial infections (amorphic alleles) to mild disseminated mycobacterial disease (hypomorphic alleles) to chronic mucocutaneous candidiasis (CMC; hypermorphic alleles). The hypermorphic mutations are also associated with arterial aneurysms, autoimmunity, and squamous cell cancers. Objective We sought to investigate the role of STAT1 gain-of-function mutations in phenotypes other than CMC. Methods We initially screened patients with CMC and autoimmunity for STAT1 mutations. We functionally characterized mutations in vitro and studied immune profiles and regulatory T (Treg) cells. After our initial case identifications, we explored 2 large cohorts of patients with wild-type forkhead box protein 3 and an immune dysregulation–polyendocrinopathy–enteropathy–X-linked (IPEX)–like phenotype for STAT1 mutations. Results We identified 5 children with polyendocrinopathy, enteropathy, and dermatitis reminiscent of IPEX syndrome; all but 1 had a variety of mucosal and disseminated fungal infections. All patients lacked forkhead box protein 3 mutations but had uniallelic STAT1 mutations (c.629 G>T, p.R210I; c.1073 T>G, p.L358W, c.796G>A; p.V266I; c.1154C>T, T385M [2 patients]). STAT1 phosphorylation in response to IFN-γ, IL-6, and IL-21 was increased and prolonged. CD4 + IL-17–producing T-cell numbers were diminished. All patients had normal Treg cell percentages in the CD4 + T-cell compartment, and their function was intact in the 2 patients tested. Patients with cells available for study had normal levels of IL-2–induced STAT5 phosphorylation. Conclusions Gain-of-function mutations in STAT1 can cause an IPEX-like phenotype with normal frequency and function of Treg cells.

"nAutoimmune polyglandular syndrome (APS) type 2 is characterized by the presence of Addison's disease, in association with autoimmune thyroid disease and/or type 1 diabetes mellitus. APS type 2 occurs most often in middle aged females and is rare in children. Here an 11 year old boy is reported with Addison's disease who developed symptom's of diabetes mellitus, goiter, malabsorption, macrocytic anemia and keratitis. APS type 2 occurs most often in middle aged females and is quite rare in children but one should think to autoimmune poly glandular syndrome type II in patient at any age especially in patients with Addison's disease.