Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
J Allergy Clin Immunol ; 145(1): 345-357.e9, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31600547

RESUMO

BACKGROUND: Patients with signal transducer and activator of transcription 5b (STAT5b) deficiency have impairment in T-cell homeostasis and natural killer (NK) cells which leads to autoimmunity, recurrent infections, and combined immune deficiency. OBJECTIVE: In this study we characterized the NK cell defect in STAT5b-deficient human NK cells, as well as Stat5b-/- mice. METHODS: We used multiparametric flow cytometry, functional NK cell assays, microscopy, and a Stat5b-/- mouse model to elucidate the effect of impaired and/or absent STAT5b on NK cell development and function. RESULTS: This alteration generated a nonfunctional CD56bright NK cell subset characterized by low cytokine production. The CD56dim NK cell subset had decreased expression of perforin and CD16 and a greater frequency of cells expressing markers of immature NK cells. We observed low NK cell numbers and impaired NK cell maturation, suggesting that STAT5b is involved in terminal NK cell maturation in Stat5b-/- mice. Furthermore, human STAT5b-deficient NK cells had low cytolytic capacity, and fixed-cell microscopy showed poor convergence of lytic granules. This was accompanied by decreased expression of costimulatory and activating receptors. Interestingly, granule convergence and cytolytic function were restored after IL-2 stimulation. CONCLUSIONS: Our results show that in addition to the impaired terminal maturation of NK cells, human STAT5b mutation leads to impairments in early activation events in NK cell lytic synapse formation. Our data provide further insight into NK cell defects caused by STAT5b deficiency.

2.
Curr Opin Pediatr ; 31(6): 843-850, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31693596

RESUMO

PURPOSE OF REVIEW: The Janus kinase (JAK) and signal transducer of activation (STAT) pathway plays a key role in the immune system. It is employed by diverse cytokines, interferons, growth factors and related molecules. Mutations in JAK/STAT pathway have been implicated in human disease. Here we review JAK/STAT biology and diseases associated with mutations in this pathway. RECENT FINDINGS: Over the past 10 years, many mutations in JAK/STAT pathway has been discovered. These disorders have provided insights to human immunology. SUMMARY: In this review, we summarize the biology of each STAT and JAK as well as discuss the human disease that results from somatic or germline mutations to include typical presentation, immunological parameters and treatment.

4.
Front Pediatr ; 7: 303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31417880

RESUMO

Nuclear factor kappa-B subunit 2 (NF-κB2/p100/p52), encoded by NFKB2 (MIM: 164012) belongs to the NF-κB family of transcription factors that play a critical role in inflammation, immunity, cell proliferation, differentiation and survival. Heterozygous C-terminal mutations in NFKB2 have been associated with early-onset common variable immunodeficiency (CVID), central adrenal insufficiency and ectodermal dysplasia. Only two previously reported cases have documented decreased natural killer (NK) cell cytotoxicity, and little is known about the role of NF-κB2 in NK cell maturation and function. Here we report a 13-year-old female that presented at 6 years of age with a history of early onset recurrent sinopulmonary infections, progressive hair loss, and hypogamaglobulinemia consistent with a clinical diagnosis of CVID. At 9 years of age she had cytomegalovirus (CMV) pneumonia that responded to ganciclovir treatment. Functional NK cell testing demonstrated decreased NK cell cytotoxicity despite normal NK cell numbers, consistent with a greater susceptibility to systemic CMV infection. Research exome sequencing (ES) was performed and revealed a novel de novo heterozygous nonsense mutation in NFKB2 (c.2611C>T, p.Gln871*) that was not carried by either of her parents. The variant was Sanger sequenced and confirmed to be de novo in the patient. At age 12, she presented with a reactivation of the systemic CMV infection that was associated with severe and progressive nephrotic syndrome with histologic evidence of pedicellar effacement and negative immunofluorescence. To our knowledge, this is the third NF-κB2 deficient patient in which an abnormal NK cell function has been observed, suggesting a role for non-canonical NF-κB2 signaling in NK cell cytotoxicity. NK cell function should be assessed in patients with mutations in the non-canonical NF-κB pathway to explore the risk for systemic viral infections that may lead to severe complications and impact patient survival. Similarly NF-κB2 should be considered in patients with combined immunodeficiency who have aberrant NK cell function. Further studies are needed to characterize the role of NF-κB2 in NK cell cytotoxic function.

5.
J Clin Immunol ; 39(7): 653-667, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31376032

RESUMO

INTRODUCTION: Inflammatory bowel disease (IBD) affects approximately 1/3 of patients with chronic granulomatous disease (CGD). Comprehensive investigation of the effect of allogeneic hematopoietic cell transplantation (HCT) on CGD IBD and the impact of IBD on transplant outcomes is lacking. METHODS: We collected data retrospectively from 145 patients with CGD who had received allogeneic HCT at 26 Primary Immune Deficiency Treatment Consortium (PIDTC) centers between January 1, 2005 and June 30, 2016. RESULTS: Forty-nine CGD patients with IBD and 96 patients without IBD underwent allogeneic HCT. Eighty-nine percent of patients with IBD and 93% of patients without IBD engrafted (p = 0.476). Upper gastrointestinal acute GVHD occurred in 8.5% of patients with IBD and 3.5% of patients without IBD (p = 0.246). Lower gastrointestinal acute GVHD occurred in 10.6% of patients with IBD and 11.8% of patients without IBD (p = 0.845). The cumulative incidence of acute GVHD grades II-IV was 30% (CI 17-43%) in patients with IBD and 20% (CI 12-29%) in patients without IBD (p = 0.09). Five-year overall survival was equivalent for patients with and without IBD: 80% [CI 66-89%] and 83% [CI 72-90%], respectively (p = 0.689). All 33 surviving evaluable patients with a history of IBD experienced resolution of IBD by 2 years following allogeneic HCT. CONCLUSIONS: In this cohort, allogeneic HCT was curative for CGD-associated IBD. IBD should not contraindicate HCT, as it does not lead to an increased risk of mortality. This study is registered at clinicaltrials.gov NCT02082353.

6.
Front Pediatr ; 7: 130, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31069200

RESUMO

Autosomal dominant hyper-IgE syndrome caused by mutations in the transcription factor STAT3 (AD-HIES) is characterized by a collection of immunologic and non-immune features including eczema, recurrent infections, elevated IgE levels, and connective tissue anomalies. We report the case of a Qatari child with a history of recurrent staphylococcal skin infections since infancy, who was found to have a novel, de novo mutation in STAT3 (c.1934T>A, p.L645Q). The absence of mucocutaneous candidiasis and undetectable IgE levels until the age of 7 years prolonged the time to molecular confirmation of the cause for the patient's immune deficiency. STAT3 p.L645Q was found to have decreased transcriptional capacity. The patient also had low levels of Th17 cells and STAT3 phosphorylation was impaired in patient-derived cells. Nearly 100 unique mutations in STAT3 have been reported in association with AD-HIES.

7.
Front Pediatr ; 7: 160, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31114772

RESUMO

In this report, we describe a novel T437N STAT1 mutation found in a mother and 3 of her 4 children which we demonstrate yields gain-of-function. All of the four patients with the T437N STAT1 mutation experienced lymphadenopathy. However, two of the children developed Nodular Lymphocyte Predominant Hodgkin Lymphoma (NHLPL) and have responded to chemotherapeutic regimens. The fourth sibling had neither the STAT1 variant nor lymphadenopathy or malignancy. To our knowledge this is the first description of a potential association between STAT1 GOF mutations and lymphoma development.

8.
Curr Allergy Asthma Rep ; 19(3): 19, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30847722

RESUMO

The section heading that reads PI3K100δ Deficiency should be corrected to read PI3K110δ Deficiency.

9.
J Allergy Clin Immunol Pract ; 7(6): 1958-1969.e9, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30825606

RESUMO

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3) gain-of-function (GOF) germline mutations have been recently described. A comprehensive overview of this early-onset multiorgan autoimmune and lymphoproliferative disease has not yet been compiled. OBJECTIVE: We have conducted a systematic review of published STAT3 GOF cases to describe clinical, diagnostic, and therapeutic aspects of the disease. METHODS: A systematic review including articles published before October 10, 2018, in PubMed, Web of Science, and Cochrane Central Register of Controlled Trials databases was performed. We described cases of patients with STAT3 GOF germline mutations with genetic analysis and a concordant phenotype if functional analyses were not performed for the mutation. RESULTS: The search identified 18 publications describing 42 unique patients. Twenty-eight different mutations were described. Onset of disease was very early with an average age of 3 (0.5-5) years. The most frequent manifestations were autoimmune cytopenias (28 of 42), lymphoproliferation (27 of 42), enteropathy (24 of 42), interstitial lung disease (15 of 42), thyroiditis (13 of 42), diabetes (10 of 42), and postnatal growth failure (15 of 21). Immunodeficiency was not always a predominant feature. Most patients required significant immunosuppressive therapy. Five patients received hematopoietic stem cell transplantation, and 4 died from complications. Improvement of symptoms was observed for 8 of 9 patients who received targeted biotherapies. CONCLUSIONS: STAT3 GOF syndrome is a new clinical entity to consider when confronted with a patient with early-onset polyautoimmunity, lymphoproliferation, and growth failure. At this time, precise therapeutic guidelines are lacking, but use of anti-IL-6 receptor and JAK inhibitor biologics is an attractive possibility.

10.
J Allergy Clin Immunol Pract ; 7(3): 761-773, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30832891

RESUMO

Advances in understanding the mechanism, immunobiology, and pathophysiology of primary immunodeficiency diseases have created opportunities for the use of precision medicines for the treatment of disease-related manifestations. Modulation of the immune system to treat autoimmunity began with the use of intravenous immunoglobulin, improved with the development of monoclonal antibodies, and has now become standard in certain diseases with mechanistic-based targets that alter the molecular mechanism of disease. In this article, we review targeted therapies for disorders of hyperinflammation, primary immunodysregulatory diseases, and primary immunodeficiencies. We also look to the future where gene editing will tailor therapy in an even more precise way for each individual disease and patient.

11.
Mol Immunol ; 115: 21-30, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30704805

RESUMO

NK cells are important early effectors in the innate immune response to a variety of viral infections and for elimination of tumor cells. The JAK/STAT signaling cascade is critical for NK cell development, maturation, survival, and proliferation, therefore, it is important to understand the role of this pathway in NK cell biology. Many cytokines can activate multiple JAK/STAT protein family members, creating a severe phenotype when mutations impair their function or expression. Here we discuss the impact of defective JAK/STAT signaling pathways on NK cell development, activation and cytotoxicity.


Assuntos
Janus Quinases/imunologia , Células Matadoras Naturais/imunologia , Fatores de Transcrição STAT/imunologia , Animais , Humanos , Imunidade Inata/imunologia , Transdução de Sinais/imunologia
13.
Curr Allergy Asthma Rep ; 19(1): 2, 2019 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-30661124

RESUMO

PURPOSE OF REVIEW: Natural killer cells are innate lymphoid cells (ILCs) that play critical roles in human host defense and are especially useful in combating viral pathogens and malignancy. RECENT FINDINGS: The NK cell deficiency (NKD) is particularly underscored in patients with a congenital immunodeficiency in which NK cell development or function is affected. The classical NK cell deficiency (cNKD) is a result of absent or a profound decrease in the number of circulating NK cells. In contrast, functional NKD (fNKD) is characterized by abnormal NK cell function but with normal number of NK cells. The combined immune deficiencies with significant impact on NK cells are not considered classical or functional NK cell deficiencies. In these disorders, the impairment of NK cells represents an important aspect of the overall immunodeficiency. In turn, this leads to improved insights on the NK cell development and function. Here, we detail the NK cell biology based upon recent natural killer cell defects described in combined immune deficiencies.


Assuntos
Síndromes de Imunodeficiência/imunologia , Células Matadoras Naturais/imunologia , Humanos
17.
Am J Hum Genet ; 102(6): 1126-1142, 2018 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-29805043

RESUMO

The proteasome processes proteins to facilitate immune recognition and host defense. When inherently defective, it can lead to aberrant immunity resulting in a dysregulated response that can cause autoimmunity and/or autoinflammation. Biallelic or digenic loss-of-function variants in some of the proteasome subunits have been described as causing a primary immunodeficiency disease that manifests as a severe dysregulatory syndrome: chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature (CANDLE). Proteasome maturation protein (POMP) is a chaperone for proteasome assembly and is critical for the incorporation of catalytic subunits into the proteasome. Here, we characterize and describe POMP-related autoinflammation and immune dysregulation disease (PRAID) discovered in two unrelated individuals with a unique constellation of early-onset combined immunodeficiency, inflammatory neutrophilic dermatosis, and autoimmunity. We also begin to delineate a complex genetic mechanism whereby de novo heterozygous frameshift variants in the penultimate exon of POMP escape nonsense-mediated mRNA decay (NMD) and result in a truncated protein that perturbs proteasome assembly by a dominant-negative mechanism. To our knowledge, this mechanism has not been reported in any primary immunodeficiencies, autoinflammatory syndromes, or autoimmune diseases. Here, we define a unique hypo- and hyper-immune phenotype and report an immune dysregulation syndrome caused by frameshift mutations that escape NMD.


Assuntos
Predisposição Genética para Doença , Chaperonas Moleculares/genética , Mutação/genética , Degradação do RNAm Mediada por Códon sem Sentido/genética , Sequência de Bases , Linhagem Celular , Estresse do Retículo Endoplasmático , Éxons/genética , Família , Mutação da Fase de Leitura/genética , Heterozigoto , Humanos , Síndromes de Imunodeficiência/genética , Imunofenotipagem , Recém-Nascido , Inflamação/patologia , Interferon Tipo I/metabolismo , Masculino , Proteínas Mutantes/metabolismo , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Síndrome , Resposta a Proteínas não Dobradas
18.
Blood ; 132(1): 89-100, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29632024

RESUMO

The HLH-2004 criteria are used to diagnose hemophagocytic lymphohistiocytosis (HLH), yet concern exists for their misapplication, resulting in suboptimal treatment of some patients. We sought to define the genomic spectrum and associated outcomes of a diverse cohort of children who met the HLH-2004 criteria. Genetic testing was performed clinically or through research-based whole-exome sequencing. Clinical metrics were analyzed with respect to genomic results. Of 122 subjects enrolled over the course of 17 years, 101 subjects received genetic testing. Biallelic familial HLH (fHLH) gene defects were identified in only 19 (19%) and correlated with presentation at younger than 1 year of age (P < .0001). Digenic fHLH variants were observed but lacked statistical support for disease association. In 28 (58%) of 48 subjects, research whole-exome sequencing analyses successfully identified likely molecular explanations, including underlying primary immunodeficiency diseases, dysregulated immune activation and proliferation disorders, and potentially novel genetic conditions. Two-thirds of patients identified by the HLH-2004 criteria had underlying etiologies for HLH, including genetic defects, autoimmunity, and malignancy. Overall survival was 45%, and increased mortality correlated with HLH triggered by infection or malignancy (P < .05). Differences in survival did not correlate with genetic profile or extent of therapy. HLH should be conceptualized as a phenotype of critical illness characterized by toxic activation of immune cells from different underlying mechanisms. In most patients with HLH, targeted sequencing of fHLH genes remains insufficient for identifying pathogenic mechanisms. Whole-exome sequencing, however, may identify specific therapeutic opportunities and affect hematopoietic stem cell transplantation options for these patients.


Assuntos
Testes Genéticos , Genoma Humano , Sequenciamento de Nucleotídeos em Larga Escala , Linfo-Histiocitose Hemofagocítica/genética , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Humanos , Lactente , Recém-Nascido , Linfo-Histiocitose Hemofagocítica/patologia , Linfo-Histiocitose Hemofagocítica/terapia , Masculino , Herança Multifatorial
19.
Biol Blood Marrow Transplant ; 24(8): 1643-1650, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29630926

RESUMO

There is a lack of consensus regarding the role and method of hematopoietic stem cell transplantation (HSCT) on patients with chronic granulomatous disease (CGD). Long-term follow-up after HSCT in these patient population is essential to know its potential complications and decide who will benefit the most from HSCT. We report the outcome of HSCT and long-term follow-up in 24 patients with CGD, transplanted in our center from either related (n = 6) or unrelated (n = 18) donors, over a 12-year period (2003 to 2015), using high-dose alemtuzumab in the preparative regimen. We evaluated the incidence and timing of adverse events and potential risk factors. We described in detailed the novel finding of increased autoimmunity after HSCT in patients with CGD. At a median follow-up of 1460 days, 22 patients were full donor chimeras, and 2 patients had stable mixed chimerism. All assessable patients showed normalization of their neutrophil oxidative burst test. None of the patients developed grades II to IV acute graft-versus-host disease, and no patient had chronic graft-versus-host disease. Twelve of 24 patients developed 17 autoimmune diseases (ADs). Severe ADs (cytopenia and neuropathy) occurred exclusively in the unrelated donor setting and mainly in the first year after HSCT, whereas thyroid AD occurred in the related donor setting as well and more than 3 years after HSCT. Two patients died due to infectious complications after developing autoimmune cytopenias. One additional patient suffered severe brain injury. The remaining 21 patients have long-term Lansky scores ≥ 80. The outcome of HSCT from unrelated donors is comparable with related donors but might carry an increased risk of developing severe AD. A lower dose of alemtuzumab may reduce this risk and should be tested in further studies.


Assuntos
Alemtuzumab/uso terapêutico , Doenças Autoimunes/etiologia , Doença Granulomatosa Crônica/complicações , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Quimerismo , Seguimentos , Doença Granulomatosa Crônica/terapia , Síndrome de Guillain-Barré/etiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Incidência , Pancitopenia/etiologia , Doadores não Relacionados
20.
J Allergy Clin Immunol ; 142(2): 605-617.e7, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29330011

RESUMO

BACKGROUND: Heterozygous gain-of-function mutations in PI3K110δ lead to lymphadenopathy, lymphoid hyperplasia, EBV and cytomegalovirus viremia, and sinopulmonary infections. OBJECTIVE: The known role of natural killer (NK) cell function in the control of EBV and cytomegalovirus prompted us to investigate the functional and phenotypic effects of PI3K110δ mutations on NK cell subsets and cytotoxic function. METHODS: Mutations in patients were identified by using whole-exome or targeted sequencing. We performed NK cell phenotyping and functional analysis of patients' cells using flow cytometry, standard Cr51 cytotoxicity assays, and quantitative confocal microscopy. RESULTS: PI3K110δ mutations led to an altered NK cell developmental phenotype and cytotoxic dysfunction. Impaired NK cell cytotoxicity was due to decreased conjugate formation with susceptible target cells and abrogated activation of cell machinery required for target cell killing. These defects were restored partially after initiation of treatment with rapamycin in 3 patients. CONCLUSION: We describe novel NK cell functional deficiency caused by PI3K110δ mutation, which is a likely contributor to the severe viremia observed in these patients. Rapamycin treatment partially restores NK cell function, providing a further rationale for its use in patients with this disease.


Assuntos
Infecções por Citomegalovirus/genética , Citomegalovirus/fisiologia , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/fisiologia , Síndromes de Imunodeficiência/genética , Células Matadoras Naturais/fisiologia , Mutação/genética , Fosfatidilinositol 3-Quinases/genética , Sirolimo/uso terapêutico , Diferenciação Celular , Células Cultivadas , Citotoxicidade Imunológica/efeitos dos fármacos , Heterozigoto , Humanos , Síndromes de Imunodeficiência/tratamento farmacológico , Sinapses Imunológicas/metabolismo , Imunofenotipagem , Ativação Linfocitária , Microscopia Confocal , Viremia , Sequenciamento Completo do Exoma
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA