Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 42
Filtrar
1.
Front Immunol ; 15: 1374499, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562931

RESUMO

Autoimmune Addison's disease (AAD) is a rare but life-threatening endocrine disorder caused by an autoimmune destruction of the adrenal cortex. A previous genome-wide association study (GWAS) has shown that common variants near immune-related genes, which mostly encode proteins participating in the immune response, affect the risk of developing this condition. However, little is known about the contribution of copy number variations (CNVs) to AAD susceptibility. We used the genome-wide genotyping data from Norwegian and Swedish individuals (1,182 cases and 3,810 controls) to investigate the putative role of CNVs in the AAD aetiology. Although the frequency of rare CNVs was similar between cases and controls, we observed that larger deletions (>1,000 kb) were more common among patients (OR = 4.23, 95% CI 1.85-9.66, p = 0.0002). Despite this, none of the large case-deletions were conclusively pathogenic, and the clinical presentation and an AAD-polygenic risk score were similar between cases with and without the large CNVs. Among deletions exclusive to individuals with AAD, we highlight two ultra-rare deletions in the genes LRBA and BCL2L11, which we speculate might have contributed to the polygenic risk in these carriers. In conclusion, rare CNVs do not appear to be a major cause of AAD but further studies are needed to ascertain the potential contribution of rare deletions to the polygenic load of AAD susceptibility.


Assuntos
Doença de Addison , Humanos , Doença de Addison/genética , Doença de Addison/patologia , Variações do Número de Cópias de DNA , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras de Transdução de Sinal/genética
2.
Clin Genet ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38361102

RESUMO

Familial exudative vitreoretinopathy (FEVR) is linked to disruption of the Norrin/Frizzled-4 signaling pathway, which plays an important role in retinal angiogenesis. Severe or complete knock-down of proteins in the pathway also causes syndromic forms of the condition. Both heterozygous and biallelic pathogenic variants in the FZD4 gene, encoding the pathway's key protein frizzled-4, are known to cause FEVR. However, it is not clear what effect different FZD4 variants have, and whether extraocular features should be expected in those with biallelic pathogenic FZD4 variants. Biallelic FZD4 variants were found in a young boy with isolated, severe FEVR. His parents were heterozygous for one variant each and reported normal vision. In-vitro studies of the two variants, demonstrated that it was the combination of the two which led to severe inhibition of the Norrin/Frizzled-4 pathway. Our observations demonstrate that biallelic FZD4-variants are associated with a severe form of FEVR, which does not necessarily include extraocular features. In addition, variants causing severe FEVR in combination, may have no or minimal effect in heterozygous parents as non-penetrance is also a major feature in dominant FZD4-FEVR disease. This underscores the importance of genetic testing of individuals and families with FEVR.

3.
Hum Reprod ; 39(1): 177-189, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37953503

RESUMO

STUDY QUESTION: Is it possible to find the cause of primary ovarian insufficiency (POI) in more women by extensive screening? SUMMARY ANSWER: Adding next generation sequencing techniques including a POI-associated gene panel, extended whole exome sequencing data, as well as specific autoantibody assays to the recommended diagnostic investigations increased the determination of a potential etiological diagnosis of POI from 11% to 41%. WHAT IS KNOWN ALREADY: POI affects ∼1% of women. Clinical presentations and pathogenic mechanisms are heterogeneous and include genetic, autoimmune, and environmental factors, but the underlying etiology remains unknown in the majority of cases. STUDY DESIGN, SIZE, DURATION: Prospective cross-sectional study of 100 women with newly diagnosed POI of unknown cause consecutively referred to Haukeland University Hospital, Bergen, Norway, January 2019 to December 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: In addition to standard recommended diagnostic investigations including screening for chromosomal anomalies and premutations in the fragile X mental retardation 1 gene (FMR1) we used whole exome sequencing, including targeted analysis of 103 ovarian-related genes, and assays of autoantibodies against steroid cell antigens. MAIN RESULTS AND THE ROLE OF CHANCE: We identified chromosomal aberrations in 8%, FMR1 premutations in 3%, genetic variants related to POI in 16%, and autoimmune POI in 3%. Furthermore in 11% we identified POI associated genetic Variants of unknown signifcance (VUS). A homozygous pathogenic variant in the ZSWIM7 gene (NM_001042697.2) was found in two women, corroborating this as a novel cause of monogenic POI. No associations between phenotypes and genotypes were found. LIMITATIONS, REASONS FOR CAUTION: Use of candidate genetic and autoimmune markers limit the possibility to discover new markers. To further investigate the genetic variants, family studies would have been useful. We found a relatively high proportion of genetic variants in women from Africa and lack of genetic diversity in the genomic databases can impact diagnostic accuracy. WIDER IMPLICATIONS OF THE FINDINGS: Since no specific clinical or biochemical markers predicted the underlying cause of POI discussion of which tests should be part of diagnostic screening in clinical practice remains open. New technology has altered the availability and effectiveness of genetic testing, and cost-effectiveness analyses are required to aid sustainable diagnostics. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by grants and fellowships from Stiftelsen Kristian Gerhard Jebsen, the Novonordisk Foundation, the Norwegian Research Council, University of Bergen, and the Regional Health Authorities of Western Norway. The authors declare no conflict of interest. TRIAL REGISTRATION NUMBER: NCT04082169.


Assuntos
Insuficiência Ovariana Primária , Humanos , Feminino , Insuficiência Ovariana Primária/diagnóstico , Insuficiência Ovariana Primária/genética , Mutação , Estudos Transversais , Autoanticorpos , Estudos Prospectivos , Proteína do X Frágil de Retardo Mental/genética
4.
J Clin Invest ; 133(21)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37909333

RESUMO

Autoimmune polyendocrine syndrome type 1 (APS-1) is caused by mutations in the autoimmune regulator (AIRE) gene. Most patients present with severe chronic mucocutaneous candidiasis and organ-specific autoimmunity from early childhood, but the clinical picture is highly variable. AIRE is crucial for negative selection of T cells, and scrutiny of different patient mutations has previously highlighted many of its molecular mechanisms. In patients with a milder adult-onset phenotype sharing a mutation in the canonical donor splice site of intron 7 (c.879+1G>A), both the predicted altered splicing pattern with loss of exon 7 (AireEx7-/-) and normal full-length AIRE mRNA were found, indicating leaky rather than abolished mRNA splicing. Analysis of a corresponding mouse model demonstrated that the AireEx7-/- mutant had dramatically impaired transcriptional capacity of tissue-specific antigens in medullary thymic epithelial cells but still retained some ability to induce gene expression compared with the complete loss-of-function AireC313X-/- mutant. Our data illustrate an association between AIRE activity and the severity of autoimmune disease, with implications for more common autoimmune diseases associated with AIRE variants, such as primary adrenal insufficiency, pernicious anemia, type 1 diabetes, and rheumatoid arthritis.


Assuntos
Doenças Autoimunes , Poliendocrinopatias Autoimunes , Adulto , Animais , Pré-Escolar , Humanos , Camundongos , Mutação , Poliendocrinopatias Autoimunes/genética , RNA Mensageiro , Linfócitos T
5.
medRxiv ; 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37503126

RESUMO

Pubertal timing varies considerably and has been associated with a range of health outcomes in later life. To elucidate the underlying biological mechanisms, we performed multi-ancestry genetic analyses in ~800,000 women, identifying 1,080 independent signals associated with age at menarche. Collectively these loci explained 11% of the trait variance in an independent sample, with women at the top and bottom 1% of polygenic risk exhibiting a ~11 and ~14-fold higher risk of delayed and precocious pubertal development, respectively. These common variant analyses were supported by exome sequence analysis of ~220,000 women, identifying several genes, including rare loss of function variants in ZNF483 which abolished the impact of polygenic risk. Next, we implicated 660 genes in pubertal development using a combination of in silico variant-to-gene mapping approaches and integration with dynamic gene expression data from mouse embryonic GnRH neurons. This included an uncharacterized G-protein coupled receptor GPR83, which we demonstrate amplifies signaling of MC3R, a key sensor of nutritional status. Finally, we identified several genes, including ovary-expressed genes involved in DNA damage response that co-localize with signals associated with menopause timing, leading us to hypothesize that the ovarian reserve might signal centrally to trigger puberty. Collectively these findings extend our understanding of the biological complexity of puberty timing and highlight body size dependent and independent mechanisms that potentially link reproductive timing to later life disease.

6.
Clin Dysmorphol ; 32(3): 97-105, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37195326

RESUMO

MSMO1 deficiency (OMIM #616834) is an ultrarare autosomal recessive disorder of distal cholesterol metabolism with only five cases reported to date. The disorder is caused by missense variants in the MSMO1 gene encoding methylsterol monooxygenase 1, leading to the accumulation of methylsterols. Clinically, MSMO1 deficiency is characterized by growth and developmental delay, often in association with congenital cataracts, microcephaly, psoriasiform dermatitis and immune dysfunction. Treatment with oral and topical cholesterol supplements and statins was reported to improve the biochemical, immunological, and cutaneous findings, supporting a potential treatment following the precision diagnosis of MSMO1 deficiency. We describe two siblings from a consanguineous family presenting with novel clinical features of polydactyly, alopecia and spasticity. Whole-exome sequencing revealed a novel, homozygous c.548A > C, p.(Glu183Ala) variant. Based on previously published treatment algorithms, we initiated a modified dosage regime with systemic cholesterol supplementation, statins and bile acid along with topical application of a cholesterol/statin formulation. This resulted in a marked improvement of psoriasiform dermatitis and some hair growth.


Assuntos
Dermatite , Inibidores de Hidroximetilglutaril-CoA Redutases , Microcefalia , Transtornos do Neurodesenvolvimento , Polidactilia , Humanos , Colesterol/metabolismo , Microcefalia/diagnóstico , Dermatite/genética , Alopecia/diagnóstico , Alopecia/tratamento farmacológico , Alopecia/genética , Linhagem
7.
J Autoimmun ; 133: 102917, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191466

RESUMO

BACKGROUND: Autoantibodies against type I interferons (IFN) alpha (α) and omega (ω), and interleukins (IL) 17 and 22 are a hallmark of autoimmune polyendocrine syndrome type 1 (APS-1), caused by mutations in the autoimmune regulator (AIRE) gene. Such antibodies are also seen in a number of monogenic immunodeficiencies. OBJECTIVES: To determine whether screening for cytokine autoantibodies (anti-IFN-ω and anti-IL22) can be used to identify patients with monogenic immune disorders. METHODS: A novel ELISA assay was employed to measure IL22 autoantibodies in 675 patients with autoimmune primary adrenal insufficiency (PAI) and a radio immune assay (RIA) was used to measure autoantibodies against IFN-ω in 1778 patients with a variety of endocrine diseases, mostly of autoimmune aetiology. Positive cases were sequenced for all coding exons of the AIRE gene. If no AIRE mutations were found, we applied next generation sequencing (NGS) to search for mutations in immune related genes. RESULTS: We identified 29 patients with autoantibodies against IFN-ω and/or IL22. Of these, four new APS-1 cases with disease-causing variants in AIRE were found. In addition, we identified two patients with pathogenic heterozygous variants in CTLA4 and NFKB2, respectively. Nine rare variants in other immune genes were identified in six patients, although further studies are needed to determine their disease-causing potential. CONCLUSION: Screening of cytokine autoantibodies can efficiently identify patients with previously unknown monogenic and possible oligogenic causes of autoimmune and immune deficiency diseases. This information is crucial for providing personalised treatment and follow-up of patients and their relatives.


Assuntos
Autoanticorpos , Doenças do Sistema Endócrino , Humanos , Citocinas
8.
Am J Med Genet A ; 188(4): 1065-1074, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34921505

RESUMO

Variants in transcription factor GLI2 have been associated with hypopituitarism and structural brain abnormalities, occasionally including holoprosencephaly (HPE). Substantial phenotypic variability and nonpenetrance have been described, posing difficulties in the counseling of affected families. We present three individuals with novel likely pathogenic GLI2 variants, two with truncating and one with a de novo missense variant p.(Ser548Leu), and review the literature for comprehensive phenotypic descriptions of individuals with confirmed pathogenic (a) intragenic GLI2 variants and (b) chromosome 2q14.2 deletions encompassing only GLI2. We show that most of the 31 missense variants previously reported as pathogenic are likely benign or, at most, low-risk variants. Four Zn-finger variants: p.(Arg479Gly), p.(Arg516Pro), p.(Gly518Lys), and p.(Tyr575His) were classified as likely pathogenic, and three other variants as possibly pathogenic: p.(Pro253Ser), p.(Ala593Val), and p.(Pro1243Leu). We analyze the phenotypic descriptions of 60 individuals with pathogenic GLI2 variants and evidence a morbidity spectrum that includes hypopituitarism (58%), HPE (6%) or other brain structure abnormalities (15%), orofacial clefting (17%) and dysmorphic facial features (35%). We establish that truncating and Zn-finger variants in GLI2 are associated with a high risk of hypopituitarism, and that a solitary median maxillary central incisor is part of the GLI2-related phenotypic variability. The most prevalent phenotypic feature is post-axial polydactyly (65%) which is also the mildest phenotypic expression of the condition, reported in many parents of individuals with systemic findings. Our approach clarifies clinical risks and the important messages to discuss in counseling for a pathogenic GLI2 variant.


Assuntos
Holoprosencefalia , Hipopituitarismo , Holoprosencefalia/genética , Humanos , Hipopituitarismo/genética , Hipopituitarismo/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Mutação , Proteínas Nucleares/genética , Fenótipo , Zinco , Proteína Gli2 com Dedos de Zinco/genética
9.
Front Immunol ; 12: 742848, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721410

RESUMO

Objectives: CD8+ T cells targeting 21-hydroxylase (21OH) are presumed to play a central role in the destruction of adrenocortical cells in autoimmune Addison's disease (AAD). Earlier reports have suggested two immunodominant CD8+ T cell epitopes within 21OH: LLNATIAEV (21OH342-350), restricted by HLA-A2, and EPLARLEL (21OH431-438), restricted by HLA-B8. We aimed to characterize polyclonal CD8+ T cell responses to the proposed epitopes in a larger patient cohort with AAD. Methods: Recombinant fluorescent HLA-peptide multimer reagents were used to quantify antigen-specific CD8+ T cells by flow cytometry. Interferon-gamma (IFNγ) Elispot and biochemical assays were used to functionally investigate the 21OH-specific T cells, and to map the exactly defined epitopes of 21OH. Results: We found a significantly higher frequency of HLA-A2 restricted LLNATIAEV-specific cells in patients with AAD than in controls. These cells could also be expanded in vitro in an antigen specific manner and displayed a robust antigen-specific IFNγ production. In contrast, only negligible frequencies of EPLARLEL-specific T cells were detected in both patients and controls with limited IFNγ response. However, significant IFNγ production was observed in response to a longer peptide encompassing EPLARLEL, 21OH430-447, suggesting alternative dominant epitopes. Accordingly, we discovered that the slightly offset ARLELFVVL (21OH434-442) peptide is a novel dominant epitope restricted by HLA-C7 and not by HLA-B8 as initially postulated. Conclusion: We have identified two dominant 21OH epitopes targeted by CD8+ T cells in AAD, restricted by HLA-A2 and HLA-C7, respectively. To our knowledge, this is the first HLA-C7 restricted epitope described for an autoimmune disease.


Assuntos
Doença de Addison/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígeno HLA-A2/imunologia , Antígenos HLA-C/imunologia , Esteroide 21-Hidroxilase/imunologia , Epitopos de Linfócito T/imunologia , Humanos , Epitopos Imunodominantes/imunologia
10.
Eur J Endocrinol ; 184(4): 607-615, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34665570

RESUMO

BACKGROUND: The most common cause of primary adrenal failure (Addison's disease) in the Western world is autoimmunity characterized by autoantibodies against the steroidogenic enzyme 21-hydroxylase (CYP21A2, 21OH). Detection of 21OH-autoantibodies is currently used for aetiological diagnosis, but how levels of 21OH-autoantibodies vary over time is not known. SETTING: Samples from the national Norwegian Addison's Registry and Biobank established in 1996 (n = 711). Multi-parameter modelling of the course of 21OH-autoantibody indices over time. RESULTS: 21OH-autoantibody positivity is remarkably stable, and >90% of the patients are still positive 30 years after diagnosis. Even though the antibody levels decline with disease duration, it is only rarely that this downturn reaches negativity. 21OH-autoantibody indices are affected by age at diagnosis, sex, type of Addison's disease (isolated vs autoimmune polyendocrine syndrome type I or II) and HLA genotype. CONCLUSION: 21OH-autoantibodies are reliable and robust markers for autoimmune Addison's disease, linked to HLA risk genotype. However, a negative test in patients with long disease duration does not exclude autoimmune aetiology.


Assuntos
Doença de Addison/sangue , Doença de Addison/diagnóstico , Autoanticorpos/sangue , Esteroide 21-Hidroxilase/sangue , Adolescente , Adulto , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Front Immunol ; 12: 722860, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34526996

RESUMO

Autoimmune polyendocrine syndrome type I (APS-1) is a monogenic model disorder of organ-specific autoimmunity caused by mutations in the Autoimmune regulator (AIRE) gene. AIRE facilitates the expression of organ-specific transcripts in the thymus, which is essential for efficient removal of dangerous self-reacting T cells and for inducing regulatory T cells (Tregs). Although reduced numbers and function of Tregs have been reported in APS-I patients, the impact of AIRE deficiency on gene expression in these cells is unknown. Here, we report for the first time on global transcriptional patterns of isolated Tregs from APS-1 patients compared to healthy subjects. Overall, we found few differences between the groups, although deviant expression was observed for the genes TMEM39B, SKIDA1, TLN2, GPR15, FASN, BCAR1, HLA-DQA1, HLA-DQB1, HLA-DRA, GPSM3 and AKR1C3. Of significant interest, the consistent downregulation of GPR15 may indicate failure of Treg gut homing which could be of relevance for the gastrointestinal manifestations commonly seen in APS-1. Upregulated FASN expression in APS-1 Tregs points to increased metabolic activity suggesting a putative link to faulty Treg function. Functional studies are needed to determine the significance of these findings for the immunopathogenesis of APS-1 and for Treg immunobiology in general.


Assuntos
Ácido Graxo Sintase Tipo I/metabolismo , Poliendocrinopatias Autoimunes/imunologia , Poliendocrinopatias Autoimunes/metabolismo , Linfócitos T Reguladores/imunologia , Adulto , Estudos de Casos e Controles , Ácido Graxo Sintase Tipo I/genética , Feminino , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Metabolismo dos Lipídeos/imunologia , Masculino , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/genética , Linfócitos T Reguladores/metabolismo
12.
J Exp Med ; 218(11)2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34477806

RESUMO

The autoimmune regulator (AIRE) is essential for the establishment of central tolerance and prevention of autoimmunity. Interestingly, different AIRE mutations cause autoimmunity in either recessive or dominant-negative manners. Using engineered mouse models, we establish that some monoallelic mutants, including C311Y and C446G, cause breakdown of central tolerance. By using RNAseq, ATACseq, ChIPseq, and protein analyses, we dissect the underlying mechanisms for their dominancy. Specifically, we show that recessive mutations result in a lack of AIRE protein expression, while the dominant mutations in both PHD domains augment the expression of dysfunctional AIRE with altered capacity to bind chromatin and induce gene expression. Finally, we demonstrate that enhanced AIRE expression is partially due to increased chromatin accessibility of the AIRE proximal enhancer, which serves as a docking site for AIRE binding. Therefore, our data not only elucidate why some AIRE mutations are recessive while others dominant, but also identify an autoregulatory mechanism by which AIRE negatively modulates its own expression.


Assuntos
Homeostase/genética , Mutação/genética , Fatores de Transcrição/genética , Animais , Autoimunidade/genética , Cromatina/genética , Dissecação/métodos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Modelos Animais
13.
J Neurooncol ; 154(1): 35-40, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34213706

RESUMO

INTRODUCTION: Vestibular schwannoma (VS) is a benign intracranial tumor in which the underlying genetics is largely uncertain, apart from mutations in the tumor suppressor gene NF2. Alternative tumorigenic mechanisms have been proposed, including a recurrent in-frame fusion transcript of the HTRA1 and SH3PXD2A genes. The gene product of the SH3PXD2A-HTRA1 fusion has been shown to promote proliferation, invasion and resistance to cell death in vitro and tumor growth in vivo. The aim of this study was to replicate the findings and to investigate the frequency of this fusion gene in another cohort of vestibular schwannoma patients. METHODS: The SH3PXD2A-HTRA1 transcript was synthesized in vitro using PCR and used as a positive control to assess the sensitivity of a real-time PCR assay. This real-time PCR assay was used to search for the presence of the fusion transcript in 121 Norwegian sporadic VS patients. RESULTS: The real-time PCR assay showed a high sensitivity and was able to detect as low as ~ 5 copies of the fusion transcript. Out of the 121 investigated tumors, only 1 harbored the SH3PXD2A-HTRA1 fusion. CONCLUSION: Even though the SH3PXD2A-HTRA1 fusion has been shown to be a driver of tumorigenesis, our results suggest that it is a rare event in our VS patients. Further investigation is warranted in order to elucidate whether our results represent an extreme, and if the fusion is present also in other neoplasms.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular , Serina Peptidase 1 de Requerimento de Alta Temperatura A , Neuroma Acústico , Proteínas de Fusão Oncogênica , Proteínas Adaptadoras de Transporte Vesicular/genética , Serina Peptidase 1 de Requerimento de Alta Temperatura A/genética , Humanos , Neuroma Acústico/genética , Noruega , Proteínas de Fusão Oncogênica/genética
14.
Hum Mutat ; 42(6): 745-761, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33942428

RESUMO

KARS1 encodes a lysyl-transfer RNA synthetase (LysRS) that links lysine to its cognate transfer RNA. Two different KARS1 isoforms exert functional effects in cytosol and mitochondria. Bi-allelic pathogenic variants in KARS1 have been associated to sensorineural hearing and visual loss, neuropathy, seizures, and leukodystrophy. We report the clinical, biochemical, and neuroradiological features of nine individuals with KARS1-related disorder carrying 12 different variants with nine of them being novel. The consequences of these variants on the cytosol and/or mitochondrial LysRS were functionally validated in yeast mutants. Most cases presented with severe neurological features including congenital and progressive microcephaly, seizures, developmental delay/intellectual disability, and cerebral atrophy. Oculo-motor dysfunction and immuno-hematological problems were present in six and three cases, respectively. A yeast growth defect of variable severity was detected for most variants on both cytosolic and mitochondrial isoforms. The detrimental effects of two variants on yeast growth were partially rescued by lysine supplementation. Congenital progressive microcephaly, oculo-motor dysfunction, and immuno-hematological problems are emerging phenotypes in KARS1-related disorder. The data in yeast emphasize the role of both mitochondrial and cytosolic isoforms in the pathogenesis of KARS1-related disorder and supports the therapeutic potential of lysine supplementation at least in a subset of patients.


Assuntos
Anormalidades Múltiplas/genética , Lisina-tRNA Ligase/genética , Anormalidades Múltiplas/metabolismo , Anormalidades Múltiplas/patologia , Adolescente , Alelos , Encefalopatias Metabólicas Congênitas/complicações , Encefalopatias Metabólicas Congênitas/genética , Encefalopatias Metabólicas Congênitas/patologia , Criança , Pré-Escolar , Estudos de Coortes , Citosol/metabolismo , Progressão da Doença , Feminino , Homozigoto , Humanos , Lactente , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Microcefalia/complicações , Microcefalia/genética , Microcefalia/patologia , Mitocôndrias/genética , Mitocôndrias/metabolismo , Organismos Geneticamente Modificados , Linhagem , Fenótipo , Saccharomyces cerevisiae
15.
Nat Commun ; 12(1): 959, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574239

RESUMO

Autoimmune Addison's disease (AAD) is characterized by the autoimmune destruction of the adrenal cortex. Low prevalence and complex inheritance have long hindered successful genetic studies. We here report the first genome-wide association study on AAD, which identifies nine independent risk loci (P < 5 × 10-8). In addition to loci implicated in lymphocyte function and development shared with other autoimmune diseases such as HLA, BACH2, PTPN22 and CTLA4, we associate two protein-coding alterations in Autoimmune Regulator (AIRE) with AAD. The strongest, p.R471C (rs74203920, OR = 3.4 (2.7-4.3), P = 9.0 × 10-25) introduces an additional cysteine residue in the zinc-finger motif of the second PHD domain of the AIRE protein. This unbiased elucidation of the genetic contribution to development of AAD points to the importance of central immunological tolerance, and explains 35-41% of heritability (h2).


Assuntos
Doença de Addison/genética , Estudo de Associação Genômica Ampla , Fatores de Transcrição de Zíper de Leucina Básica/genética , Antígeno CTLA-4/genética , Feminino , Humanos , Masculino , Modelos Moleculares , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Risco
16.
J Endocr Soc ; 5(3): bvaa202, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33553982

RESUMO

BACKGROUND: No reliable biomarkers exist to guide glucocorticoid (GC) replacement treatment in autoimmune Addison's disease (AAD), leading to overtreatment with alarming and persistent side effects or undertreatment, which could be fatal. OBJECTIVE: To explore changes in gene expression following different GC replacement doses as a means of identifying candidate transcriptional biomarkers to guide GC replacement in AAD. METHODS: Step 1: Global microarray expression analysis on RNA from whole blood before and after intravenous infusion of 100 mg hydrocortisone (HC) in 10 patients with AAD. In 3 of the most highly upregulated genes, we performed real-time PCR (rt-PCR) to compare gene expression levels before and 3, 4, and 6 hours after the HC infusion. Step 2: Rt-PCR to compare expression levels of 93 GC-regulated genes in normal versus very low morning cortisol levels in 27 patients with AAD. RESULTS: Step 1: Two hours after infusion of 100 mg HC, there was a marked increase in FKBP5, MMP9, and DSIPI expression levels. MMP9 and DSIPI expression levels correlated with serum cortisol. Step 2: Expression levels of CEBPB, DDIT4, FKBP5, DSIPI, and VDR were increased and levels of ADARB1, ARIDB5, and POU2F1 decreased in normal versus very low morning cortisol. Normal serum cortisol levels positively correlated with DSIPI, DDIT4, and FKBP5 expression. CONCLUSIONS: We introduce gene expression as a novel approach to guide GC replacement in AAD. We suggest that gene expression of DSIPI, DDIT4, and FKBP5 are particularly promising candidate biomarkers of GC replacement, followed by MMP9, CEBPB, VDR, ADARB1, ARID5B, and POU2F1.

17.
Immun Inflamm Dis ; 8(3): 342-359, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32578964

RESUMO

BACKGROUND: Glioblastoma (GBM) is an aggressive malignant brain tumor where median survival is approximately 15 months after best available multimodal treatment. Recurrence is inevitable, largely due to O6 methylguanine DNA methyltransferase (MGMT) that renders the tumors resistant to temozolomide (TMZ). We hypothesized that pretreatment with bortezomib (BTZ) 48 hours prior to TMZ to deplete MGMT levels would be safe and tolerated by patients with recurrent GBM harboring unmethylated MGMT promoter. The secondary objective was to investigate whether 26S proteasome blockade may enhance differentiation of cytotoxic immune subsets to impact treatment responses measured by radiological criteria and clinical outcomes. METHODS: Ten patients received intravenous BTZ 1.3 mg/m2 on days 1, 4, and 7 during each 4th weekly TMZ-chemotherapy starting on day 3 and escalated from 150 mg/m2 per oral 5 days/wk via 175 to 200 mg/m2 in cycles 1, 2, and 3, respectively. Adverse events and quality of life were evaluated by CTCAE and EQ-5D-5L questionnaire, and immunological biomarkers evaluated by flow cytometry and Luminex enzyme-linked immunosorbent assay. RESULTS: Sequential BTZ + TMZ therapy was safe and well tolerated. Pain and performance of daily activities had greatest impact on patients' self-reported quality of life and were inversely correlated with Karnofsky performance status. Patients segregated a priori into three groups, where group 1 displayed stable clinical symptoms and/or slower magnetic resonance imaging radiological progression, expanded CD4+ effector T-cells that attenuated cytotoxic T-lymphocyte associated protein-4 and PD-1 expression and secreted interferon γ and tumor necrosis factor α in situ and ex vivo upon stimulation with PMA/ionomycin. In contrast, rapidly progressing group 2 patients exhibited tolerised T-cell phenotypes characterized by fourfold to sixfold higher interleukin 4 (IL-4) and IL-10 Th-2 cytokines after BTZ + TMZ treatment, where group 3 patients exhibited intermediate clinical/radiological responses. CONCLUSION: Sequential BTZ + TMZ treatment is safe and promotes Th1-driven immunological responses in selected patients with improved clinical outcomes (Clinicaltrial.gov (NCT03643549)).


Assuntos
Glioblastoma , Adulto , Antineoplásicos Alquilantes/uso terapêutico , Bortezomib/uso terapêutico , Dacarbazina/uso terapêutico , Combinação de Medicamentos , Feminino , Glioblastoma/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Qualidade de Vida , Temozolomida/uso terapêutico
18.
Artigo em Inglês | MEDLINE | ID: mdl-31611844

RESUMO

Background: Underlying causes of adrenal insufficiency include congenital adrenal hyperplasia (CAH) and autoimmune adrenocortical destruction leading to autoimmune Addison's disease (AAD). Here, we report a patient with a homozygous stop-gain mutation in 3ß-hydroxysteroid dehydrogenase type 2 (3ßHSD2), in addition to impaired steroidogenesis due to AAD. Case Report: Whole exome sequencing revealed an extremely rare homozygous nonsense mutation in exon 2 of the HSD3B2 gene, leading to a premature stop codon (NM_000198.3: c.15C>A, p.Cys5Ter) in a patient with AAD and premature ovarian insufficiency. Scrutiny of old medical records revealed that the patient was initially diagnosed with CAH with hyperandrogenism and severe salt-wasting shortly after birth. However, the current steroid profile show complete adrenal insufficiency including low production of pregnenolone, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S), without signs of overtreatment with steroids. Conclusion: To the best of our knowledge, this is the first description of autoimmune adrenalitis in a patient with 3ßHSD2 deficiency and suggests a possible association between AAD and inborn errors of the steroidogenesis.

19.
J Transl Autoimmun ; 1: 100005, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32743495

RESUMO

Autoimmune Addison's disease (AAD) is a classic organ-specific autoimmune disease characterized by an immune-mediated attack on the adrenal cortex. As most autoimmune diseases, AAD is believed to be caused by a combination of genetic and environmental factors, and probably interactions between the two. Persistent viral infections have been suggested to play a triggering role, by invoking inflammation and autoimmune destruction. The inability of clearing infections can be due to aberrations in innate immunity, including mutations in genes involved in the recognition of conserved microbial patterns. In a whole exome sequencing study of anonymized AAD patients, we discovered several rare variants predicted to be damaging in the gene encoding Toll-like receptor 3 (TLR3). TLR3 recognizes double stranded RNAs, and is therefore a major factor in antiviral defense. We here report the occurrence and functional characterization of five rare missense variants in TLR3 of patients with AAD. Most of these variants occurred together with a common TLR3 variant that has been associated with a wide range of immunopathologies. The biological implications of these variants on TLR3 function were evaluated in a cell-based assay, revealing a partial loss-of-function effect of three of the rare variants. In addition, rare mutations in other members of the TLR3-interferon (IFN) signaling pathway were detected in the AAD patients. Together, these findings indicate a potential role for TLR3 and downstream signaling proteins in the pathogenesis in a subset of AAD patients.

20.
Exp Parasitol ; 191: 66-72, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29908864

RESUMO

INTRODUCTION/AIMS: The long-term humoral immune response after a natural giardiasis infection is not well understood. The aim of this study was to evaluate longitudinal serum IgA and IgG/M responses towards conserved regions of two Giardia variant-specific surface proteins (VSP) and whether these responses differ between Giardia assemblages and durations of infection. METHODS: We recruited thirty Giardia-positive patients, mainly returning travellers, and eighteen healthy adults presumed to be Giardia unexposed. Blood samples were collected before treatment, and at 6 weeks, 6 months and 12 months after the infection cleared. We used a multiplex bead-based flow cytometry immunoassay to measure Giardia specific IgA and IgG/M responses targeting two recombinant antigens from G. lamblia VSP proteins 3 and 5 (VSP3 and VSP5). RESULTS: Serum levels of anti-VSP5 and anti-VSP3 IgA decreased rapidly to low levels after treatment but continued to be substantially higher than that of presumed unexposed controls even after 6 and 12 months. The IgG/M response decreased more gradually but remained significantly higher than presumed unexposed controls at all time points, except for anti-VSP3 at 12 months. There were no significant difference in responses for infections with assemblage A and assemblage B Giardia lamblia. Chronic infections (>8 weeks) were associated with a significantly lower anti-VSP5 IgG/M response. CONCLUSION: This study describes the kinetics of the humoral immune response against two Giardia VSP proteins over one year, and the considerable cross reactivity between the two human infective Giardia assemblages. Persons with chronic Giardia infection seem to have lower levels of VSP antibodies.


Assuntos
Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Giardia lamblia/imunologia , Giardíase/imunologia , Proteínas de Protozoários/imunologia , Doença Aguda , Adulto , Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/química , Estudos de Casos e Controles , Doença Crônica , Estudos de Coortes , Reações Cruzadas , Ensaio de Imunoadsorção Enzimática , Feminino , Giardíase/diagnóstico , Humanos , Imunoensaio/métodos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Cinética , Estudos Longitudinais , Masculino , Microesferas , Pessoa de Meia-Idade , Noruega , Proteínas de Protozoários/química , Sensibilidade e Especificidade , Fatores de Tempo , Viagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...