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1.
Nat Immunol ; 20(9): 1208-1219, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31384057

RESUMO

Regulatory T cells (Treg cells) deficient in the transcription factor Foxp3 lack suppressor function and manifest an effector T (Teff) cell-like phenotype. We demonstrate that Foxp3 deficiency dysregulates metabolic checkpoint kinase mammalian target of rapamycin (mTOR) complex 2 (mTORC2) signaling and gives rise to augmented aerobic glycolysis and oxidative phosphorylation. Specific deletion of the mTORC2 adaptor gene Rictor in Foxp3-deficient Treg cells ameliorated disease in a Foxo1 transcription factor-dependent manner. Rictor deficiency re-established a subset of Treg cell genetic circuits and suppressed the Teff cell-like glycolytic and respiratory programs, which contributed to immune dysregulation. Treatment of Treg cells from patients with FOXP3 deficiency with mTOR inhibitors similarly antagonized their Teff cell-like program and restored suppressive function. Thus, regulatory function can be re-established in Foxp3-deficient Treg cells by targeting their metabolic pathways, providing opportunities to restore tolerance in Treg cell disorders.


Assuntos
Reprogramação Celular/imunologia , Fatores de Transcrição Forkhead/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina/genética , Linfócitos T Reguladores/imunologia , Animais , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Glicólise/fisiologia , Humanos , Masculino , Alvo Mecanístico do Complexo 2 de Rapamicina/antagonistas & inibidores , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação Oxidativa , Transdução de Sinais , Linfócitos T Reguladores/citologia
2.
Front Immunol ; 10: 1740, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396234

RESUMO

Advances in flow cytometry have led to greatly improved primary immunodeficiency (PID) diagnostics. This is due to the fact that patient blood cells in suspension do not require further processing for analysis by flow cytometry, and many PIDs lead to alterations in leukocyte numbers, phenotype, and function. A large portion of current PID assays can be classified as "phenotyping" assays, where absolute numbers, frequencies, and markers are investigated using specific antibodies. Inherent drawbacks of antibody technology are the main limitation to this type of testing. On the other hand, "functional" assays measure cellular responses to certain stimuli. While these latter assays are powerful tools that can be used to detect defects in entire pathways and distinguish variants of significance, it requires samples with robust viability and also skilled processing. In this review, we concentrate on hemophagocytic lymphohistiocytosis (HLH), describing the principles and accuracies of flow cytometric assays that have been proven to assist in the screening diagnosis of primary HLH.

3.
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.

4.
J Allergy Clin Immunol Pract ; 7(6): 1970-1985.e4, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30877075

RESUMO

BACKGROUND: Although autoimmunity and hyperinflammation secondary to recombination activating gene (RAG) deficiency have been associated with delayed diagnosis and even death, our current understanding is limited primarily to small case series. OBJECTIVE: Understand the frequency, severity, and treatment responsiveness of autoimmunity and hyperinflammation in RAG deficiency. METHODS: In reviewing the literature and our own database, we identified 85 patients with RAG deficiency, reported between 2001 and 2016, and compiled the largest case series to date of 63 patients with prominent autoimmune and/or hyperinflammatory pathology. RESULTS: Diagnosis of RAG deficiency was delayed a median of 5 years from the first clinical signs of immune dysregulation. Most patients (55.6%) presented with more than 1 autoimmune or hyperinflammatory complication, with the most common etiologies being cytopenias (84.1%), granulomas (23.8%), and inflammatory skin disorders (19.0%). Infections, including live viral vaccinations, closely preceded the onset of autoimmunity in 28.6% of cases. Autoimmune cytopenias had early onset (median, 1.9, 2.1, and 2.6 years for autoimmune hemolytic anemia, immune thrombocytopenia, and autoimmune neutropenia, respectively) and were refractory to intravenous immunoglobulin, steroids, and rituximab in most cases (64.7%, 73.7%, and 71.4% for autoimmune hemolytic anemia, immune thrombocytopenia, and autoimmune neutropenia, respectively). Evans syndrome specifically was associated with lack of response to first-line therapy. Treatment-refractory autoimmunity/hyperinflammation prompted hematopoietic stem cell transplantation in 20 patients. CONCLUSIONS: Autoimmunity/hyperinflammation can be a presenting sign of RAG deficiency and should prompt further evaluation. Multilineage cytopenias are often refractory to immunosuppressive treatment and may require hematopoietic cell transplantation for definitive management.

5.
Blood ; 132(17): 1737-1749, 2018 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-30154114

RESUMO

The Primary Immune Deficiency Treatment Consortium (PIDTC) performed a retrospective analysis of 662 patients with severe combined immunodeficiency (SCID) who received a hematopoietic cell transplantation (HCT) as first-line treatment between 1982 and 2012 in 33 North American institutions. Overall survival was higher after HCT from matched-sibling donors (MSDs). Among recipients of non-MSD HCT, multivariate analysis showed that the SCID genotype strongly influenced survival and immune reconstitution. Overall survival was similar for patients with RAG, IL2RG, or JAK3 defects and was significantly better compared with patients with ADA or DCLRE1C mutations. Patients with RAG or DCLRE1C mutations had poorer immune reconstitution than other genotypes. Although survival did not correlate with the type of conditioning regimen, recipients of reduced-intensity or myeloablative conditioning had a lower incidence of treatment failure and better T- and B-cell reconstitution, but a higher risk for graft-versus-host disease, compared with those receiving no conditioning or immunosuppression only. Infection-free status and younger age at HCT were associated with improved survival. Typical SCID, leaky SCID, and Omenn syndrome had similar outcomes. Landmark analysis identified CD4+ and CD4+CD45RA+ cell counts at 6 and 12 months post-HCT as biomarkers predictive of overall survival and long-term T-cell reconstitution. Our data emphasize the need for patient-tailored treatment strategies depending upon the underlying SCID genotype. The prognostic significance of CD4+ cell counts as early as 6 months after HCT emphasizes the importance of close follow-up of immune reconstitution to identify patients who may need additional intervention to prevent poor long-term outcome.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Transplante de Células-Tronco Hematopoéticas , Reconstituição Imune/imunologia , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/mortalidade , Imunodeficiência Combinada Severa/terapia , Genótipo , Humanos , Contagem de Linfócitos , Estudos Retrospectivos
6.
J Clin Immunol ; 38(4): 540-541, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29781065

RESUMO

The original version of this article unfortunately contained mistakes in some of the author names and affiliations. The correct list of author names and affiliations is below, with the corrections in bold.

7.
Biol Blood Marrow Transplant ; 24(7): 1527-1529, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29555312

RESUMO

Mixed chimerism and eventual graft loss occurs in a proportion of children with primary immune deficiencies receiving alemtuzumab, fludarabine, and melphalan reduced-intensity conditioning (RIC) regimens before allogeneic hematopoietic stem cell transplantation (HSCT). We investigated the usefulness of a CD34+ selected stem cell "boost" without conditioning to treat mixed chimerism in children and young adults who received predominantly an alemtuzumab, fludarabine, and melphalan RIC regimen for primary immune deficiencies and reported the outcomes. Patients with a primary immune deficiency disorder who were either enrolled on a prospective CD34+ boost study for treatment of mixed chimerism from 2011 to 2014 (n = 9) or treated with a CD34+ boost on a clinical basis from 2014 to 2016 (n = 3) were included in this analysis. Response to a CD34+ boost was defined as a rise in donor chimerism by ≥15% with donor chimerism of at least 20%, stabilization was defined as a rise in chimerism by <15% with donor chimerism ≥ 20%, and no response was defined as any decline in donor chimerism or need for a second HSCT after a CD34+ boost. Twelve patients received alemtuzumab, fludarabine, and melphalan. Median age was 4.5 years (range, .9 to 20.6), and median whole blood donor chimerism before the boost was 25% (range, 3% to 61%). Three patients (25%) met criteria for response, 1 patient (8%) was considered to have stabilization, and 8 patients (67%) had no response 12 months after the boost. None of the patients developed any complications from a CD34+ boost, including no acute graft-versus-host disease (GVHD). All patients are alive with a median follow-up of 32 months (range, 8 to 79). We conclude that a CD34+ selected stem cell boost can be considered for treatment of mixed chimerism after alemtuzumab, fludarabine, and melphalan RIC HSCT in children and young adults with primary immune deficiencies. Approximately one-third of patients can be expected to benefit from a CD34+ selected stem cell boost and may avoid the need for a second HSCT. Lack of any GVHD or toxicity makes a stem cell boost an attractive option compared with donor lymphocyte infusions for treatment of mixed chimerism.


Assuntos
Antígenos CD34/uso terapêutico , Quimerismo/induzido quimicamente , Transplante de Células-Tronco Hematopoéticas/métodos , Síndromes de Imunodeficiência/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Síndromes de Imunodeficiência/patologia , Lactente , Recém-Nascido , Masculino , Adulto Jovem
9.
J Allergy Clin Immunol ; 141(3): 1036-1049.e5, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29241729

RESUMO

BACKGROUND: Immunodysregulation polyendocrinopathy enteropathy x-linked (IPEX) syndrome is a monogenic autoimmune disease caused by FOXP3 mutations. Because it is a rare disease, the natural history and response to treatments, including allogeneic hematopoietic stem cell transplantation (HSCT) and immunosuppression (IS), have not been thoroughly examined. OBJECTIVE: This analysis sought to evaluate disease onset, progression, and long-term outcome of the 2 main treatments in long-term IPEX survivors. METHODS: Clinical histories of 96 patients with a genetically proven IPEX syndrome were collected from 38 institutions worldwide and retrospectively analyzed. To investigate possible factors suitable to predict the outcome, an organ involvement (OI) scoring system was developed. RESULTS: We confirm neonatal onset with enteropathy, type 1 diabetes, and eczema. In addition, we found less common manifestations in delayed onset patients or during disease evolution. There is no correlation between the site of mutation and the disease course or outcome, and the same genotype can present with variable phenotypes. HSCT patients (n = 58) had a median follow-up of 2.7 years (range, 1 week-15 years). Patients receiving chronic IS (n = 34) had a median follow-up of 4 years (range, 2 months-25 years). The overall survival after HSCT was 73.2% (95% CI, 59.4-83.0) and after IS was 65.1% (95% CI, 62.8-95.8). The pretreatment OI score was the only significant predictor of overall survival after transplant (P = .035) but not under IS. CONCLUSIONS: Patients receiving chronic IS were hampered by disease recurrence or complications, impacting long-term disease-free survival. When performed in patients with a low OI score, HSCT resulted in disease resolution with better quality of life, independent of age, donor source, or conditioning regimen.


Assuntos
Diabetes Mellitus Tipo 1/congênito , Diarreia , Fatores de Transcrição Forkhead , Doenças Genéticas Ligadas ao Cromossomo X , Transplante de Células-Tronco Hematopoéticas , Doenças do Sistema Imunitário/congênito , Imunossupressão , Mutação , Adolescente , Adulto , Aloenxertos , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/mortalidade , Diabetes Mellitus Tipo 1/terapia , Diarreia/genética , Diarreia/imunologia , Diarreia/mortalidade , Diarreia/terapia , Intervalo Livre de Doença , Feminino , Seguimentos , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Doenças Genéticas Ligadas ao Cromossomo X/mortalidade , Doenças Genéticas Ligadas ao Cromossomo X/terapia , Humanos , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/imunologia , Doenças do Sistema Imunitário/mortalidade , Doenças do Sistema Imunitário/terapia , Lactente , Masculino , Estudos Retrospectivos , Taxa de Sobrevida
10.
J Pediatr ; 186: 183-185, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28457527

RESUMO

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is caused by mutations in the FOXP3 gene. Patients usually present with a clinical triad of intractable diarrhea, diabetes, and eczema. In this patient, FOXP3 protein expression was normal, but FOXP3 Sanger sequencing confirmed the clinical suspicion of IPEX by detecting a previously unreported missense variant. Early recognition of IPEX is important, because hematopoietic stem cell transplantation can be curative.


Assuntos
Diabetes Mellitus Tipo 1/congênito , Diarreia/diagnóstico , Diarreia/genética , Fatores de Transcrição Forkhead/genética , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças do Sistema Imunitário/congênito , Pré-Escolar , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Diarreia/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Humanos , Doenças do Sistema Imunitário/diagnóstico , Doenças do Sistema Imunitário/genética , Doenças do Sistema Imunitário/metabolismo , Masculino
12.
Blood ; 129(22): 2993-2999, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28270454

RESUMO

Primary hemophagocytic lymphohistiocytosis (HLH) can be caused by biallelic mutations in PRF1, encoding perforin, or UNC13D, STXBP2, STX11, RAB27A, LYST, and AP3B1, encoding proteins involved in cytotoxic lymphocyte degranulation. Natural killer (NK)-cell cytotoxicity assays can quickly screen for all of these genetic diseases, facilitating treatment, but combining NK-cell perforin expression and CD107a upregulation tests can as well. To determine the relative diagnostic accuracies for each approach, we retrospectively reviewed screening test performance in 1614 patients referred for HLH evaluation. For each test, we generated a receiver operating characteristic (ROC) curve, and calculated area under the curve (AUC) and diagnostic parameters at optimal threshold. We generated an AUC for combining perforin and CD107a tests by creating a logistic regression model and applying model-generated coefficients to patient values. Sensitivities of NK-cell function, perforin mean channel fluorescence (MCF), and CD107a MCF to detect biallelic mutations were 59.5%, 96.6%, and 93.8%, with specificities of 72.0%, 99.5%, and 73%. AUCs for NK-cell cytotoxicity, perforin MCF, CD107a MCF, and combined perforin and CD107a MCFs were 0.690, 0.971, 0.860, and 0.838. Perforin and CD107a tests are more sensitive and no less specific compared with NK cytotoxicity testing for screening for genetic HLH and should be considered for addition to current HLH criteria.


Assuntos
Células Matadoras Naturais/imunologia , Linfo-Histiocitose Hemofagocítica/diagnóstico , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Perforina/metabolismo , Adolescente , Adulto , Idoso , Degranulação Celular , Criança , Pré-Escolar , Testes Imunológicos de Citotoxicidade , Análise Mutacional de DNA , Feminino , Citometria de Fluxo , Testes Genéticos , Humanos , Lactente , Recém-Nascido , Células Matadoras Naturais/metabolismo , Modelos Logísticos , Linfo-Histiocitose Hemofagocítica/genética , Linfo-Histiocitose Hemofagocítica/imunologia , Masculino , Pessoa de Meia-Idade , Mutação , Perforina/genética , Estudos Retrospectivos , Adulto Jovem
13.
Biol Blood Marrow Transplant ; 23(5): 857-860, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28219834

RESUMO

Hemophagocytic lymphohistiocytosis (HLH) is an immune regulatory disorder that commonly presents with central nervous system (CNS) involvement. The only cure for genetic HLH is hematopoietic stem cell transplantation (HSCT), typically treated with reduced-intensity conditioning (RIC) regimens. We sought to estimate the incidence of CNS relapse after RIC HSCT, determine risk factors, and evaluate outcomes. We performed a retrospective chart review of 94 consecutive children and young adults with primary HLH who received RIC HSCT. CNS relapse within 1 year after transplantation was diagnosed by review of clinical symptoms, cerebral spinal fluid (CSF), and radiologic findings. Four (4.25%) patients developed symptoms of possible CNS HLH after HSCT and 3 patients were diagnosed. Eight patients underwent screening lumbar puncture because of history of active CNS disease at the onset of the conditioning regimen and 4 had evidence of continued disease. The overall incidence of CNS relapse and continued CNS disease after RIC HSCT was 8%. All patients with CNS disease after HSCT responded to CNS-directed therapy. Whole blood donor chimerism at the time of CNS relapse was low at 1% to 34%, but it remained high at 88% to 100% for patients with continued CNS disease. Overall survival for patients with CNS relapse was 50%, compared with 75% for patients without CNS disease (P = .079). Our data suggest that a low level of donor chimerism or active CNS disease at the time of transplantation increase the risk of CNS HLH after HSCT. Surveillance CSF evaluation after allogeneic RIC HSCT should be considered in patients with risk factors and CNS-directed treatment should be initiated if appropriate.


Assuntos
Doenças do Sistema Nervoso Central/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Linfo-Histiocitose Hemofagocítica/patologia , Adolescente , Adulto , Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Doenças do Sistema Nervoso Central/diagnóstico , Doenças do Sistema Nervoso Central/terapia , Criança , Pré-Escolar , Quimerismo , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Linfo-Histiocitose Hemofagocítica/terapia , Masculino , Recidiva , Estudos Retrospectivos , Fatores de Risco , Punção Espinal , Condicionamento Pré-Transplante/efeitos adversos , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Adulto Jovem
16.
Blood ; 127(1): 17-28, 2016 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-26504182

RESUMO

Patients with autoimmune multilineage cytopenias are often refractory to standard therapies requiring chronic immunosuppression with medications with limited efficacy and high toxicity. We present data on 30 patients treated on a multicenter prospective clinical trial using sirolimus as monotherapy. All children (N = 12) with autoimmune lymphoproliferative syndrome (ALPS) achieved a durable complete response (CR), including rapid improvement in autoimmune disease, lymphadenopathy, and splenomegaly within 1 to 3 months of starting sirolimus. Double-negative T cells were no longer detectable in most, yet other lymphocyte populations were spared, suggesting a targeted effect of sirolimus. We also treated 12 patients with multilineage cytopenias secondary to common variable immunodeficiency (CVID), Evans syndrome (ES), or systemic lupus erythematosus (SLE), and most achieved a CR (N = 8), although the time to CR was often slower than was seen in ALPS. Six children with single-lineage autoimmune cytopenias were treated and only 2 responded. Sirolimus was well tolerated with very few side effects. All of the responding patients have remained on therapy for over 1 year (median, 2 years; range, 1 to 4.5 years). In summary, sirolimus led to CR and durable responses in a majority of children with refractory multilineage autoimmune cytopenias. The responses seen in ALPS patients were profound, suggesting that sirolimus should be considered as a first-line, steroid-sparing treatment of patients needing chronic therapy. The results in other multilineage autoimmune cytopenia cohorts were encouraging, and sirolimus should be considered in children with SLE, ES, and CVID. This trial was registered at www.clinicaltrials.gov as #NCT00392951.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Doenças Hematológicas/tratamento farmacológico , Imunossupressores/uso terapêutico , Recidiva Local de Neoplasia/tratamento farmacológico , Terapia de Salvação , Sirolimo/uso terapêutico , Adolescente , Adulto , Doenças Autoimunes/mortalidade , Doenças Autoimunes/patologia , Criança , Pré-Escolar , Feminino , Seguimentos , Doenças Hematológicas/mortalidade , Doenças Hematológicas/patologia , Humanos , Imunossupressores/farmacocinética , Lactente , Masculino , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Sirolimo/farmacocinética , Taxa de Sobrevida , Distribuição Tecidual , Adulto Jovem
18.
J Clin Invest ; 125(11): 4135-48, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26457731

RESUMO

Patients with mutations of the recombination-activating genes (RAG) present with diverse clinical phenotypes, including severe combined immune deficiency (SCID), autoimmunity, and inflammation. However, the incidence and extent of immune dysregulation in RAG-dependent immunodeficiency have not been studied in detail. Here, we have demonstrated that patients with hypomorphic RAG mutations, especially those with delayed-onset combined immune deficiency and granulomatous/autoimmune manifestations (CID-G/AI), produce a broad spectrum of autoantibodies. Neutralizing anti-IFN-α or anti-IFN-ω antibodies were present at detectable levels in patients with CID-G/AI who had a history of severe viral infections. As this autoantibody profile is not observed in a wide range of other primary immunodeficiencies, we hypothesized that recurrent or chronic viral infections may precipitate or aggravate immune dysregulation in RAG-deficient hosts. We repeatedly challenged Rag1S723C/S723C mice, which serve as a model of leaky SCID, with agonists of the virus-recognizing receptors TLR3/MDA5, TLR7/-8, and TLR9 and found that this treatment elicits autoantibody production. Altogether, our data demonstrate that immune dysregulation is an integral aspect of RAG-associated immunodeficiency and indicate that environmental triggers may modulate the phenotypic expression of autoimmune manifestations.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Citocinas/imunologia , Proteínas de Ligação a DNA/deficiência , Doença Granulomatosa Crônica/imunologia , Proteínas de Homeodomínio/imunologia , Proteínas Nucleares/deficiência , Imunodeficiência Combinada Severa/imunologia , Adolescente , Adulto , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Especificidade de Anticorpos , Autoanticorpos/sangue , Doenças Autoimunes/genética , Criança , Pré-Escolar , RNA Helicases DEAD-box/imunologia , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Feminino , Doença Granulomatosa Crônica/genética , Doença Granulomatosa Crônica/terapia , Proteínas de Homeodomínio/genética , Humanos , Lactente , Helicase IFIH1 Induzida por Interferon , Masculino , Camundongos , Camundongos Endogâmicos , Proteínas Nucleares/genética , Imunodeficiência Combinada Severa/genética , Imunodeficiência Combinada Severa/terapia , Receptores Toll-Like/agonistas , Receptores Toll-Like/imunologia , Viroses/imunologia , Adulto Jovem
19.
Science ; 349(6246): 436-40, 2015 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-26206937

RESUMO

Mutations in the LRBA gene (encoding the lipopolysaccharide-responsive and beige-like anchor protein) cause a syndrome of autoimmunity, lymphoproliferation, and humoral immune deficiency. The biological role of LRBA in immunologic disease is unknown. We found that patients with LRBA deficiency manifested a dramatic and sustained improvement in response to abatacept, a CTLA4 (cytotoxic T lymphocyte antigen-4)-immunoglobulin fusion drug. Clinical responses and homology of LRBA to proteins controlling intracellular trafficking led us to hypothesize that it regulates CTLA4, a potent inhibitory immune receptor. We found that LRBA colocalized with CTLA4 in endosomal vesicles and that LRBA deficiency or knockdown increased CTLA4 turnover, which resulted in reduced levels of CTLA4 protein in FoxP3(+) regulatory and activated conventional T cells. In LRBA-deficient cells, inhibition of lysosome degradation with chloroquine prevented CTLA4 loss. These findings elucidate a mechanism for CTLA4 trafficking and control of immune responses and suggest therapies for diseases involving the CTLA4 pathway.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doenças Autoimunes/tratamento farmacológico , Antígeno CTLA-4/deficiência , Imunodeficiência de Variável Comum/tratamento farmacológico , Imunoconjugados/uso terapêutico , Abatacepte , Proteínas Adaptadoras de Transdução de Sinal/genética , Adolescente , Doenças Autoimunes/metabolismo , Antígeno CTLA-4/genética , Criança , Cloroquina/farmacologia , Imunodeficiência de Variável Comum/metabolismo , Endossomos/metabolismo , Feminino , Fatores de Transcrição Forkhead/análise , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Doenças Pulmonares Intersticiais/tratamento farmacológico , Doenças Pulmonares Intersticiais/metabolismo , Ativação Linfocitária , Lisossomos/metabolismo , Masculino , Proteólise , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Adulto Jovem
20.
Biol Blood Marrow Transplant ; 21(8): 1460-70, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25865646

RESUMO

Alemtuzumab, fludarabine, and melphalan reduced-intensity conditioning (RIC) regimens are increasingly used for the hematopoietic cell transplantation (HCT) of pediatric and young adult patients with nonmalignant diseases. Early experience suggests that these regimens are associated with good survival but a high incidence of mixed chimerism, which we have previously shown to be influenced by the alemtuzumab schedule. We hypothesized that the underlying diagnosis and donor graft source would also affect the development of mixed chimerism and that the majority of patients would survive RIC HCT without graft loss. To examine this, we conducted a retrospective study of 206 patients with metabolic diseases, non-Fanconi anemia marrow failure disorders, and primary immune deficiencies who underwent 210 consecutive RIC HCT procedures at Cincinnati Children's Hospital. Ninety-seven percent of the patients engrafted. Mixed donor and recipient chimerism developed in 46% of patients. Patients with marrow failure had a low risk of mixed chimerism (hazard ratio [HR], .208; 95% confidence interval [CI], .061 to .709; P = .012). The risk of mixed chimerism was high in patients who received a cord blood graft (HR, 3.122; 95% CI, 1.236 to 7.888; P = .016). As expected, patients who received a proximal or higher dose per kilogram of alemtuzumab schedule also experienced higher rates of mixed chimerism (all HR > 2, all P < .05). At the time of last follow-up (median, 654 days; range, 13 to 3337), over 75% of patients had greater than 90% whole blood donor chimerism. A second transplantation was performed in 5% of patients. Three-year survival without retransplantation was 84% (95% CI, 71% to 98%) for patients who underwent transplantation with an HLA-matched sibling donor. Survival without retransplantation was negatively affected by lack of a matched related donor, increasing age, and development of grades III and IV acute graft-versus-host disease. We conclude that alemtuzumab, fludarabine, and melphalan RIC HCT offers good results for many patients and that the risk of developing mixed chimerism is influenced by underlying diagnosis, graft source, and alemtuzumab dosing.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Melfalan/uso terapêutico , Vidarabina/análogos & derivados , Adolescente , Adulto , Alemtuzumab , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Criança , Pré-Escolar , Quimerismo , Feminino , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Masculino , Melfalan/administração & dosagem , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/uso terapêutico , Adulto Jovem
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