RESUMO
The autoimmune regulator (AIRE) gene is crucial for establishing central immunological tolerance and preventing autoimmunity. Mutations in AIRE cause a rare autosomal-recessive disease, autoimmune polyendocrine syndrome type 1 (APS-1), distinguished by multi-organ autoimmunity. We have identified multiple cases and families with mono-allelic mutations in the first plant homeodomain (PHD1) zinc finger of AIRE that followed dominant inheritance, typically characterized by later onset, milder phenotypes, and reduced penetrance compared to classical APS-1. These missense PHD1 mutations suppressed gene expression driven by wild-type AIRE in a dominant-negative manner, unlike CARD or truncated AIRE mutants that lacked such dominant capacity. Exome array analysis revealed that the PHD1 dominant mutants were found with relatively high frequency (>0.0008) in mixed populations. Our results provide insight into the molecular action of AIRE and demonstrate that disease-causing mutations in the AIRE locus are more common than previously appreciated and cause more variable autoimmune phenotypes.
Assuntos
Análise Mutacional de DNA/métodos , Genes Dominantes/genética , Mutação/genética , Poliendocrinopatias Autoimunes/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Sequência de Aminoácidos , Autoimunidade/genética , Criança , Pré-Escolar , Feminino , Frequência do Gene , Humanos , Masculino , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Noruega , Especificidade de Órgãos/genética , Linhagem , Penetrância , Fenótipo , Federação Russa , Adulto Jovem , Proteína AIRERESUMO
A major manifestation of autoimmune polyendocrine syndrome type 1 (APS1) is hypoparathyroidism, which is suggested to result from aberrant immune responses against the parathyroid glands. The calcium-sensing receptor (CaSR), which plays a pivotal role in maintaining calcium homeostasis by sensing blood calcium levels and regulating release of parathyroid hormone (PTH), is an autoantibody target in APS1. In this study, the aim was to characterize the binding sites, specificity, functional affinity, IgG subclass, and functional effects of CaSR autoantibodies using phage-display technology, ELISA, and bioassays. The results indicated that CaSR autoantibody binding sites were at aa 41-69, 114-126, 171-195, and 260-340 in the extracellular domain of the receptor. Autoantibodies against CaSR epitopes 41-69, 171-195, and 260-340 were exclusively of the IgG1 subclass. Autoantibody responses against CaSR epitope 114-126 were predominantly of the IgG1 with a minority of the IgG3 subclass. Only autoantibodies recognizing CaSR epitopes 114-126 and 171-195 affected receptor activity; inositol-phosphate accumulation was increased significantly in HEK293-CaSR cells, and PTH secretion from PTH-C1 cells was reduced significantly when either were incubated with purified Ab and Ca2+ compared with Ca2+ alone. In conclusion, although the majority of APS1 patients do not have CaSR-stimulating autoantibodies, the hypoparathyroid state in a small minority of patients is the result of functional suppression of the parathyroid glands.
Assuntos
Epitopos de Linfócito B/metabolismo , Imunoglobulina G/metabolismo , Hormônio Paratireóideo/metabolismo , Poliendocrinopatias Autoimunes/imunologia , Receptores de Detecção de Cálcio/metabolismo , Adolescente , Adulto , Autoanticorpos/metabolismo , Cálcio/metabolismo , Criança , Pré-Escolar , Epitopos de Linfócito B/imunologia , Feminino , Células HEK293 , Humanos , Hipoparatireoidismo , Imunoglobulina G/imunologia , Masculino , Pessoa de Meia-Idade , Poliendocrinopatias Autoimunes/genética , Receptores de Detecção de Cálcio/imunologia , Fatores de Transcrição/genética , Adulto Jovem , Proteína AIRERESUMO
CONTEXT: Activating antibodies directed at the extracellular calcium-sensing receptor (CaSR) have been described in autoimmune hypoparathyroidism in the setting of isolated hypoparathyroidism or autoimmune polyglandular syndrome type 1. MATERIALS AND METHODS: A 34-year-old female presented with hypocalcaemia (6.0 mg/dL) and hypomagnesaemia (1.1 mg/dL) accompanied by low serum PTH (2.4 pg/mL) as well as urinary calcium and magnesium wasting. She was diagnosed with hypoparathyroidism, which was refractory to standard therapy. She was started on 60 mg prednisone and 150 mg azathioprine treatment daily on suspicion of an autoimmune aetiology. The patient was tested for CaSR antibodies. RESULTS: The patient was positive for CaSR antibodies of the IgG1 subtype, which stimulated phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and inositol phosphate (IP) accumulation. Post-treatment with prednisone and azathioprine, her serum calcium and magnesium normalized, as did her CaSR antibody titre and antibody-mediated stimulation of ERK1/2 phosphorylation and IP accumulation. CONCLUSION: This is the first demonstration of CaSR antibody-mediated hypoparathyroidism responsive to immunosuppressive therapy, adding to the evidence that autoimmune hypoparathyroidism can be, in some cases, reversible and not the result of autoimmune parathyroid destruction.
Assuntos
Autoanticorpos/sangue , Hipoparatireoidismo/terapia , Receptores de Detecção de Cálcio/imunologia , Adulto , Doenças Autoimunes/terapia , Feminino , Humanos , Hipoparatireoidismo/imunologia , Imunossupressores/uso terapêuticoRESUMO
OBJECTIVE: The frequency of autoimmunity against the parathyroid glands in patients with polyglandular autoimmunity that is not due to autoimmune polyendocrine syndrome type 1 (APS1) is unclear. To investigate this, this study aimed to determine the prevalence of autoantibodies against parathyroid autoantigens, calcium-sensing receptor (CaSR) and NACHT leucine-rich-repeat protein 5 (NALP5), in a large group of patients with non-APS1 polyendocrine autoimmunity. Possible occult APS1 was investigated by cytokine autoantibody measurement and AIRE gene analysis. DESIGN, SUBJECTS AND MEASUREMENTS: Subjects were 178 patients with APS2, 3 or 4, and 80 healthy blood donors. Autoantibodies against the CaSR, NALP5 and cytokines were measured by immunoprecipitation, radioligand binding assays or ELISA, respectively. RESULTS: Four patient samples (2.2%), but none of the controls, were positive for CaSR autoantibodies. NALP5 autoantibodies were not detected in any participant. Eleven patients (6.2%) had cytokine autoantibodies, but none of the control samples was positive. None of the patients with cytokine autoantibodies had any known or novel mutations in the AIRE gene. CONCLUSIONS: The low prevalence of CaSR autoantibodies indicate a very low level of subclinical parathyroid autoimmunity in APS types 2, 3 and 4. In addition, autoantibodies against cytokines constitute an uncommon feature of non-APS1 polyglandular autoimmunity.
Assuntos
Autoanticorpos/imunologia , Citocinas/imunologia , Poliendocrinopatias Autoimunes/imunologia , Receptores de Detecção de Cálcio/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Autoimunidade , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais , Proteínas Nucleares , Glândulas Paratireoides/imunologiaRESUMO
BACKGROUND: PRKDC encodes for DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a kinase that forms part of a complex (DNA-dependent protein kinase [DNA-PK]) crucial for DNA double-strand break repair and V(D)J recombination. In mice DNA-PK also interacts with the transcription factor autoimmune regulator (AIRE) to promote central T-cell tolerance. OBJECTIVE: We sought to understand the causes of an inflammatory disease with granuloma and autoimmunity associated with decreasing T- and B-cell counts over time that had been diagnosed in 2 unrelated patients. METHODS: Genetic, molecular, and functional analyses were performed to characterize an inflammatory disease evocative of a combined immunodeficiency. RESULTS: We identified PRKDC mutations in both patients. These patients exhibited a defect in DNA double-strand break repair and V(D)J recombination. Whole-blood mRNA analysis revealed a strong interferon signature. On activation, memory T cells displayed a skewed cytokine response typical of TH2 and TH1 but not TH17. Moreover, mutated DNA-PKcs did not promote AIRE-dependent transcription of peripheral tissue antigens in vitro. The latter defect correlated in vivo with production of anti-calcium-sensing receptor autoantibodies, which are typically found in AIRE-deficient patients. In addition, 9 months after bone marrow transplantation, patient 1 had Hashimoto thyroiditis, suggesting that organ-specific autoimmunity might be linked to nonhematopoietic cells, such as AIRE-expressing thymic epithelial cells. CONCLUSION: Deficiency of DNA-PKcs, a key AIRE partner, can present as an inflammatory disease with organ-specific autoimmunity, suggesting a role for DNA-PKcs in regulating autoimmune responses and maintaining AIRE-dependent tolerance in human subjects.
Assuntos
Proteína Quinase Ativada por DNA/genética , Granuloma/genética , Síndromes de Imunodeficiência/genética , Mutação , Proteínas Nucleares/genética , Neoplasias Cutâneas/genética , Fatores de Transcrição/genética , Adolescente , Animais , Autoanticorpos/biossíntese , Autoimunidade/genética , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Reparo do DNA por Junção de Extremidades/imunologia , Proteína Quinase Ativada por DNA/deficiência , Proteína Quinase Ativada por DNA/imunologia , Feminino , Regulação da Expressão Gênica , Granuloma/imunologia , Granuloma/metabolismo , Granuloma/patologia , Humanos , Tolerância Imunológica , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/metabolismo , Síndromes de Imunodeficiência/patologia , Masculino , Camundongos , Proteínas Nucleares/deficiência , Proteínas Nucleares/imunologia , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Células Th1/imunologia , Células Th1/metabolismo , Células Th1/patologia , Células Th2/imunologia , Células Th2/metabolismo , Células Th2/patologia , Fatores de Transcrição/imunologia , Recombinação V(D)J/imunologia , Adulto Jovem , Proteína AIRERESUMO
BACKGROUND: Generalized vitiligo is an autoimmune disease characterized by melanocyte loss, which results in patchy depigmentation of skin and hair, and is associated with an elevated risk of other autoimmune diseases. METHODS: To identify generalized vitiligo susceptibility loci, we conducted a genomewide association study. We genotyped 579,146 single-nucleotide polymorphisms (SNPs) in 1514 patients with generalized vitiligo who were of European-derived white (CEU) ancestry and compared the genotypes with publicly available control genotypes from 2813 CEU persons. We then tested 50 SNPs in two replication sets, one comprising 677 independent CEU patients and 1106 CEU controls and the other comprising 183 CEU simplex trios with generalized vitiligo and 332 CEU multiplex families. RESULTS: We detected significant associations between generalized vitiligo and SNPs at several loci previously associated with other autoimmune diseases. These included genes encoding major-histocompatibility-complex class I molecules (P=9.05x10(-23)) and class II molecules (P=4.50x10(-34)), PTPN22 (P=1.31x10(-7)), LPP (P=1.01x10(-11)), IL2RA (P=2.78x10(-9)), UBASH3A (P=1.26x10(-9)), and C1QTNF6 (P=2.21x10(-16)). We also detected associations between generalized vitiligo and SNPs in two additional immune-related loci, RERE (P=7.07x10(-15)) and GZMB (P=3.44x10(-8)), and in a locus containing TYR (P=1.60x10(-18)), encoding tyrosinase. CONCLUSIONS: We observed associations between generalized vitiligo and markers implicating multiple genes, some associated with other autoimmune diseases and one (TYR) that may mediate target-cell specificity and indicate a mutually exclusive relationship between susceptibility to vitiligo and susceptibility to melanoma.
Assuntos
Doenças Autoimunes/genética , Predisposição Genética para Doença , Complexo Principal de Histocompatibilidade/genética , Monofenol Mono-Oxigenase/genética , Polimorfismo de Nucleotídeo Único , Vitiligo/genética , Marcadores Genéticos , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Melanoma/genética , Vitiligo/imunologiaRESUMO
We present a case of an 82-year-old woman with elevated parathyroid hormone (PTH) levels, hypocalciuria, hypercalcemia, and stage 3 chronic kidney disease. Hypocalciuria initially was attributed to chronic kidney disease, and hypercalcemia was attributed to primary hyperparathyroidism. Subsequent laboratory studies showed autoantibodies in the patient's serum directed against the calcium-sensing receptor (CaSR). Functional testing in a CaSR-transfected human embryonic kidney-293 cell line showed that the patient's antibodies inhibited CaSR-mediated intracellular signaling that ordinarily would have been stimulated by extracellular calcium ions. Her serum calcium and PTH levels were normalized by treatment with the calcimimetic cinacalcet. We advise consideration of the presence of inhibitory autoantibodies directed at the CaSR in patients with hypercalcemic hyperparathyroidism and unexplained hypocalciuria or with confounding conditions affecting interpretation of urinary calcium measurement. A calcimimetic is an effective treatment for the hypercalcemia and elevated PTH levels in acquired hypocalciuric hypercalcemia caused by inhibitory anti-CaSR autoantibodies.
Assuntos
Autoanticorpos/sangue , Doenças Autoimunes/etiologia , Hipercalcemia/etiologia , Falência Renal Crônica/complicações , Receptores de Detecção de Cálcio/imunologia , Idoso de 80 Anos ou mais , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/imunologia , Cálcio/sangue , Feminino , Humanos , Hipercalcemia/diagnóstico , Hipercalcemia/imunologia , Hiperparatireoidismo Secundário/diagnóstico , Hiperparatireoidismo Secundário/etiologia , Hiperparatireoidismo Secundário/imunologia , Falência Renal Crônica/imunologia , Receptores de Detecção de Cálcio/antagonistas & inibidoresRESUMO
BACKGROUND: Objective parameters to assess disease activity in non-segmental vitiligo are lacking. Melanocyte antigen-specific antibodies are frequently found in the sera of patients with vitiligo and the presence of these antibodies may correlate with disease activity. OBJECTIVE: To investigate the relationship between melanocyte antigen-specific antibodies and recent disease activity in patients with vitiligo and to evaluate the potential usefulness of this objective parameter in daily clinical practice. METHODS: The prevalence of tyrosinase, melanoma antigen recognized by T-cells-1 (MART1), melanin-concentrating hormone receptor-1 (MCHR1), gp100 and tyrosine hydroxylase (TH) antibodies was evaluated in 21 patients with non-segmental vitiligo and in 20 healthy controls. RESULTS: In 21 patients, nine (42.8%) showed antibody responses against tyrosinase, MART1, MCHR1, gp100 or TH. No antibody responses were found in the 20 controls. No correlation was found between the presence of antibodies and recent disease activity or other clinical characteristics such as age, gender, extension and duration of vitiligo. CONCLUSIONS: In this study, 42.8% of the vitiligo patients showed an antibody response to melanocyte antigen-specific antigens. However, the presence of antibodies against melanocytes did not correlate with recent disease activity or other relevant disease parameters, and for the moment screening for these antibodies in individual patients does not appear to be clinically relevant.
Assuntos
Antígenos/imunologia , Autoanticorpos/sangue , Melanócitos/imunologia , Vitiligo/sangue , Vitiligo/imunologia , Adulto , Biomarcadores/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Regulatory T cells (Tregs) play an essential role in maintaining immune tolerance and suppressing inflammation. However, Tregs present major hurdle in eliciting potent anti-cancer immune responses. Therefore, curbing the activity of Tregs represents a novel and efficient way towards successful immunotherapy of cancer. Moreover, there is an emerging interest in harnessing Treg-based strategies for augmenting anti-cancer immunity in different types of the disease. This review summarises the crucial mechanisms of Tregs' mediated suppression of anti-cancer immunity and strategies to suppress or to alter such Tregs to improve the immune response against tumors. Highlighting important clinical studies, the review also describes current Treg-based therapeutic interventions in cancer, and discusses Treg-suppression by molecular targeting, which may emerge as an effective cancer immunotherapy and as an alternative to detrimental chemotherapeutic agents.
RESUMO
Accumulating studies have indicated immune-based destruction of melanocytes in both segmental vitiligo (SV) and non-SV (NSV). Whereas SV often occurs unilaterally during childhood and stabilizes after an initial period of activity, the disease course of NSV is usually slowly progressive, with new lesions occurring bilaterally during life. This suggests an involvement of distinct pathophysiology pathways, specifically increased systemic immune activation in patients with NSV but not in patients with SV. This research aimed to identify the differences in immune cells in the blood of patients with SV and NSV through immunophenotyping of circulating cells. Regulatory T cells were unaffected in patients with SV compared with that in healthy controls but decreased in patients with NSV. In patients with NSV, the reduction in regulatory T cells was associated with the presence of other systemic autoimmune comorbidities, which were less present in SV. Similarly, the absence of a melanocyte-specific antibody response in patients with SV suggests less involvement of B-cell immunity in SV. These data show that in contrast to patients with NSV, no increased systemic immunity is found in patients with SV, indicating that SV pathogenesis is associated with a localized cytotoxic reaction targeting epidermal melanocytes.
Assuntos
Vitiligo , Epiderme/patologia , Humanos , Imunofenotipagem , Melanócitos/patologia , Linfócitos T Reguladores , Vitiligo/patologiaRESUMO
Vitiligo is an acquired idiopathic hypomelanotic skin disorder characterised by depigmented macules because of loss of cutaneous melanocytes. Although the exact cause of vitiligo remains obscure, evidence suggests that autoimmunity plays a role in the pathogenesis of the disease. Previously, tyrosine hydroxylase (TH) was identified as a putative autoantigen in vitiligo using phage-display technology. In this study, the prevalence of TH antibodies in patients with vitiligo was investigated. A radioimmunoassay (RIA) was used to detect TH antibodies in sera from patients with either non-segmental vitiligo (n=79), segmental vitiligo (n=8) or other autoimmune diseases without concomitant vitiligo (n=91). Sera from healthy individuals (n=28) were also tested. Patients with segmental vitiligo, healthy controls and patients with other autoimmune diseases without concomitant vitiligo were all negative for TH antibody reactivity. Of 79 patients with non-segmental vitiligo, 18 (23%) were positive for TH antibodies in the RIA, and a significant increase in the prevalence of TH antibodies in patients with non-segmental vitiligo was evident when compared with controls (P=0.003). TH antibody prevalence was also significantly elevated in patients with active vitiligo compared to those with stable disease (P=0.009). Overall, the results indicate that TH is an antibody target in non-segmental but not in segmental vitiligo and that TH antibodies appear to be more frequent in patients with active vitiligo.
Assuntos
Autoanticorpos/sangue , Tirosina 3-Mono-Oxigenase/imunologia , Vitiligo/enzimologia , Vitiligo/imunologia , Adolescente , Adulto , Idoso , Autoantígenos/genética , Sequência de Bases , Estudos de Casos e Controles , Criança , Primers do DNA/genética , Feminino , Células HEK293 , Humanos , Masculino , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/imunologia , Radioimunoensaio , Receptores de Somatostatina/imunologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Tirosina 3-Mono-Oxigenase/genética , Vitiligo/patologia , Adulto JovemRESUMO
CONTEXT: Autoimmune hypocalciuric hypercalcemia (AHH) is an acquired disorder caused by the presence of blocking autoantibodies against the calcium-sensing receptor (CaSR). Few cases of this condition have been described to date in the literature. OBJECTIVE: The objectives of this study were to describe 2 patients in whom the presence of AHH was suspected and to assess the patients for the presence of CaSR antibodies. METHODS: CaSR antibodies were detected and characterised by immunoprecipitation assays, CaSR peptide ELISAs, and functional assays based on the calcium-stimulated accumulation of inositol-1-phosphate in a mammalian cell line expressing the CaSR. RESULTS: Both patients presented with an acquired form of hypocalciuric hypercalcemia. Mutational analyses of CASR, GNA11, and AP2S1 for familial hypocalciuric hypercalcemia were negative. According to the presence of Hashimoto's disease in 1 patient and latent autoimmune diabetes of adulthood and thyroid autoimmunity in the other, AHH was suspected. Immunoprecipitation assays detected CaSR antibodies in both patients. Analysis of the antibody binding sites revealed 2 main epitopes at amino acids 41-69 and 114-126. Preincubation with purified CaSR antibodies against epitope 114-126 resulted in a significant decrease in inositol-1-phophate accumulation upon calcium-stimulation of mammalian cells expressing the CaSR, suggesting that the antibodies had receptor-blocking activity. CONCLUSIONS: AHH is to be suspected in patients with an acquired biochemical pattern of PTH-dependant hypocalciuric hypercalcemia, especially in those with other concomitant autoimmune diseases. Diagnosis by means of detecting CaSR antibodies may help to better characterise this probably under-reported condition.
Assuntos
Doenças Autoimunes/imunologia , Hipercalcemia/imunologia , Receptores de Detecção de Cálcio/imunologia , Idoso , Autoanticorpos/sangue , Doenças Autoimunes/sangue , Doença de Hashimoto/complicações , Humanos , Hipercalcemia/sangue , Hipercalcemia/complicações , Masculino , Pessoa de Meia-IdadeRESUMO
CONTEXT: Immune checkpoint inhibitors (ICIs), such as programmed cell death protein-1 (PD-1), programmed cell death protein-ligand 1 (PD-L1), and cytotoxic T lymphocyte antigen-4 (CTLA-4) monoclonal antibodies, are approved for the treatment of some types of advanced cancer. Their main treatment-related side-effects are immune-related adverse events (irAEs), especially thyroid dysfunction and hypophysitis. Hypoparathyroidism, on the contrary, is an extremely rare irAE. OBJECTIVES: The aim of the study was to investigate the etiology of autoimmune hypoparathyroidism in a lung cancer patient treated with pembrolizumab, an anti-PD-1. METHODS: Calcium-sensing receptor (CaSR) autoantibodies, their functional activity, immunoglobulin (Ig) subclasses and epitopes involved in the pathogenesis of autoimmune hypoparathyroidism were tested. RESULTS: The patient developed hypocalcemia after 15 cycles of pembrolizumab. Calcium levels normalized with oral calcium carbonate and calcitriol and no remission of hypocalcemia was demonstrated during a 9-month follow-up. The patient was found to be positive for CaSR-stimulating antibodies, of IgG1 and IgG3 subclasses, that were able to recognize functional epitopes on the receptor, thus causing hypocalcemia. CONCLUSION: The finding confirms that ICI therapy can trigger, among other endocrinopathies, hypoparathyroidism, which can be caused by pathogenic autoantibodies.
Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Autoanticorpos/sangue , Hipoparatireoidismo/induzido quimicamente , Imunoterapia/efeitos adversos , Receptores de Detecção de Cálcio/imunologia , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/terapia , Anticorpos Monoclonais Humanizados/uso terapêutico , Humanos , Hipocalcemia/sangue , Hipocalcemia/induzido quimicamente , Hipoparatireoidismo/diagnóstico , Hipoparatireoidismo/imunologia , Hipoparatireoidismo/metabolismo , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Receptores de Detecção de Cálcio/metabolismo , Suspensão de TratamentoRESUMO
Objectives Hypoparathyroidism is a rare disease in children that occurs as a result of autoimmune destruction of the parathyroid glands, a defect in parathyroid gland development or secondary to physical parathyroid gland disturbance. Typical symptoms of hypoparathyroidism present as hypocalcaemia and hyperphosphatemia due to decreased parathyroid hormone secretion and may lead to nerve and muscles disturbances resulting in clinical manifestation of tetany, arrhythmias and epilepsy. Currently, there is no conventional hormone replacement treatment for hypoparathyroidism and therapeutic approaches include normalising mineral levels using an oral calcium supplement and active forms of vitamin D. Case presentation We present the case of a 10-year-old girl with primary hypoparathyroidism who had no prior history of autoimmune disorders, but who subsequently developed systemic lupus erythematosus.
Assuntos
Hipoparatireoidismo/complicações , Lúpus Eritematoso Sistêmico/patologia , Cálcio/administração & dosagem , Criança , Suplementos Nutricionais , Feminino , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/etiologia , Prognóstico , Vitamina D/administração & dosagem , Vitaminas/administração & dosagemRESUMO
CONTEXT: The Short Synacthen Test (SST) is the gold standard for diagnosing adrenal insufficiency. It requires invasive administration of Synacthen, venous sampling, and is resource-intensive. OBJECTIVE: To develop a nasally administered SST, with salivary glucocorticoids measurement, to assess the adrenal response. DESIGN: We conducted 5 studies: 4 open-label, sequence-randomized, crossover, pharmacodynamic studies testing 6 doses/formulations and a repeatability study. Additionally, pharmacokinetic analysis was undertaken using our chosen formulation, 500 µg tetracosactide with mucoadhesive chitosan, Nasacthin003, in our pediatric study. SETTING: Adult and children's clinical research facilities. PARTICIPANTS: A total of 36 healthy adult males and 24 healthy children. INTERVENTION: We administered all 6 nasal formulations using an European regulator endorsed atomization device. The IV comparators were 250 µg or 1 µg SST. MAIN OUTCOME MEASURES: We analyzed paired blood and saliva samples for plasma cortisol and salivary cortisol and cortisone. RESULTS: The addition of chitosan to tetracosactide and dose escalation increased peak cortisol response (Pâ =â 0.01 and 0.001, respectively). The bioavailability of Nasacthin003 was 14.3%. There was no significant difference in plasma cortisol at 60 minutes between 500 µg Nasacthin003 and 250 µg IV Synacthen (Pâ =â 0.17). The repeatability coefficient at 60 minutes was 105 nmol/L for IV Synacthen and salivary cortisol and cortisone was 10.3 and 21.1 nmol/L, respectively. The glucocorticoid response in children was indistinguishable from that of adults. CONCLUSIONS: Nasal administration of Nasacthin003 generates equivalent plasma cortisol values to the 250-µg IV SST and, with measurement at 60 minutes of salivary cortisol or cortisone, provides a noninvasive test for adrenal insufficiency.
Assuntos
Testes de Função do Córtex Suprarrenal/métodos , Insuficiência Adrenal/diagnóstico , Cosintropina/farmacocinética , Glucocorticoides/análise , Saliva/química , Administração Intranasal , Adolescente , Adulto , Criança , Quitosana/administração & dosagem , Quitosana/farmacocinética , Cosintropina/administração & dosagem , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The melanin-concentrating hormone receptor 1 (MCHR1) has been identified as a B cell autoantigen in vitiligo with antibodies to the receptor detectable in binding and function-blocking assays. Two epitope domains (amino acids 1-138 and 139-298) have been previously identified. In this study, we aimed to further define the epitope specificity of MCHR1 antibodies using phage-display technology and to identify the epitopes recognised by receptor antibodies detected in MCHR1 function-blocking assays. Antibody reactivity to MCHR1 peptides 51-80, 85-98, 154-158 and 254-260 was identified by phage-display and subsequently confirmed in phage ELISA in 2/12, 5/12, 3/12 and 6/12 of vitiligo patients, respectively. The results suggest that major autoantibody epitopes are localised in the 85-98 and 254-260 amino acid regions of MCHR1 with minor epitopes in amino acid sequences 51-80 and 154-158. Antibodies with MCHR1 function-blocking activity were determined to recognise epitope 254-260, this being the first epitope to be reported as a target site for antibodies that block the function of the receptor.
Assuntos
Autoanticorpos/química , Autoantígenos/química , Receptores do Hormônio Hipofisário/biossíntese , Receptores do Hormônio Hipofisário/química , Vitiligo/imunologia , Adulto , Doenças Autoimunes/imunologia , Sítios de Ligação , Biotinilação , Epitopos de Linfócito B/química , Feminino , Humanos , Imunoglobulina G/química , Masculino , Pessoa de Meia-Idade , Biblioteca de Peptídeos , Vitiligo/metabolismoRESUMO
Context: Whereas therapy with immune checkpoint inhibitors (ICIs), such as nivolumab, have substantially improved survival in several types of cancer, increased attention has been given to adverse immune events associated with their use, including the development of endocrine autoimmunity. Objectives: First, to describe a patient with a 2-year history of metastatic small cell lung cancer who had been treated with nivolumab a few months before presentation with the signs and symptoms of severe hypocalcemia and hypoparathyroidism. Second, to investigate the etiology of the patient's hypoparathyroidism, including the presence of activating autoantibodies against the calcium-sensing receptor (CaSR), as humoral and cellular immune responses against the CaSR have been reported in patients with autoimmune hypoparathyroidism. Participants: A 61-year-old female was admitted with persistent nausea, vomiting, epigastric pain, constipation, and generalized weakness. Laboratory analyses showed low total serum calcium, ionized calcium, and parathyroid hormone (PTH). The patient was diagnosed with severe hypocalcemia as a result of autoimmune hypoparathyroidism after testing positive for CaSR-activating autoantibodies. Interventions: She was treated with intravenous calcium gluconate infusions, followed by a transition to oral calcium carbonate, plus calcitriol, which normalized her serum calcium. Results: Her serum PTH remained low during her hospitalization and initial outpatient follow-up, despite adequate repletion of magnesium. Conclusions: This case illustrates autoimmune hypoparathyroidism induced by ICI blockade. As ICIs are now used to treat many cancers, clinicians should be aware of the potential risk for hypocalcemia that may be associated with their use.
Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Autoanticorpos/sangue , Doenças Autoimunes/induzido quimicamente , Hipoparatireoidismo/induzido quimicamente , Nivolumabe/efeitos adversos , Doenças Autoimunes/imunologia , Feminino , Humanos , Hipocalcemia/induzido quimicamente , Hipocalcemia/imunologia , Hipoparatireoidismo/imunologia , Neoplasias Pulmonares/tratamento farmacológico , Pessoa de Meia-Idade , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológicoRESUMO
The tyrosine-protein phosphatase non-receptor type 22 (PTPN22) gene was recently identified as an important genetic susceptibility factor in several autoimmune diseases. The increased risk has been broadly explained by the 1858T-allele (rs2476601). As two smaller studies on Addison's disease (AD) have shown diverging results, we aimed to elucidate the predisposing effect of the single-nucleotide polymorphism (SNP) 1858CT in a larger population of AD patients, especially focusing on the AD patients with known autoimmune etiology. We also screened for unknown rare or common variants in the PTPN22 gene that could predispose for AD. The case-control study of Norwegian AD patients (n=332) and controls (n=990) showed a significant association between autoimmune AD (n=302) and the PTPN22 1858T risk allele (P=0.016). The association of AD with 1858T was supported by a meta-analysis combining our genotype data with that of others published previously (P=0.003). The mutation screening of PTPN22 in AD patients (n=332) and controls (n=112) revealed eight missense variants, five of which have not been reported previously. In conclusion, the 1858T-allele is a PTPN22 genetic susceptibility factor for autoimmune AD. Other rare variants in PTPN22 do occur, and may also be involved in the pathogenesis.
Assuntos
Doença de Addison/genética , Mutação de Sentido Incorreto/genética , Polimorfismo de Nucleotídeo Único/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Doença de Addison/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Metanálise como Assunto , Pessoa de Meia-Idade , Noruega/epidemiologia , Reino Unido/epidemiologiaRESUMO
We report the case of a 54-year-old Caucasian female who presented with a two-year history of persistent hypocalcemia requiring multiple hospitalizations. Her medical history was significant for HIV diagnosed four years ago. She denied any history of prior neck surgery or radiation. Her vital signs were stable with an unremarkable physical exam. Pertinent medications included calcium carbonate, vitamin D3, calcitriol, efavirenz, emtricitabine, tenofovir disoproxil, hydrochlorothiazide, and inhaled budesonide/formoterol. Laboratory testing showed total calcium of 5.7 mg/dL (normal range: 8.4-10.2 mg/dL), ionized calcium of 2.7 mg/dL (normal range: 4.5-5.5 mg/dL), serum phosphate of 6.3 mg/dL (normal range: 2.7-4.5 mg/dL), and intact PTH of 7.6 pg/mL (normal range: 15-65 pg/mL). She was diagnosed with primary hypoparathyroidism. Anti-calcium-sensing receptor antibodies and NALP5 antibodies were tested and found to be negative. During subsequent clinic visits, doses of calcium supplements and calcitriol were titrated. Last corrected serum calcium level was 9.18 mg/dL. She was subsequently lost to follow-up. This case gives insight into severe symptomatic hypocalcemia from primary hypoparathyroidism attributed to HIV infection. We suggest that calcium levels should be closely monitored in patients with HIV infection.
RESUMO
Vitiligo development in melanoma patients during immunotherapy is a favorable prognostic sign and indicates breakage of tolerance against melanocytic/melanoma antigens. We investigated a novel immunotherapeutic approach of the skin-depigmenting compound monobenzone synergizing with imiquimod in inducing antimelanoma immunity and melanoma regression. Stage III-IV melanoma patients with non-resectable cutaneous melanoma metastases were treated with monobenzone and imiquimod (MI) therapy applied locally to cutaneous metastases and adjacent skin during 12 weeks, or longer. Twenty-one of 25 enrolled patients were evaluable for clinical assessment at 12 weeks. MI therapy was well-tolerated. Partial regression of cutaneous metastases was observed in 8 patients and stable disease in 1 patient, reaching the statistical endpoint of treatment efficacy. Continued treatment induced clinical response in 11 patients, including complete responses in three patients. Seven patients developed vitiligo-like depigmentation on areas of skin that were not treated with MI therapy, indicating a systemic effect of MI therapy. Melanoma-specific antibody responses were induced in 7 of 17 patients tested and melanoma-specific CD8+T-cell responses in 11 of 15 patients tested. These systemic immune responses were significantly increased during therapy as compared to baseline in responding patients. This study shows that MI therapy induces local and systemic anti-melanoma immunity and local regression of cutaneous metastases in 38% of patients, or 52% during prolonged therapy. This study provides proof-of-concept of MI therapy, a low-cost, broadly applicable and well-tolerated treatment for cutaneous melanoma metastases, attractive for further clinical investigation.