Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 106
Filtrar
2.
Haematologica ; 2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33440924

RESUMO

Pediatric-onset Evans syndrome (pES) is defined by both immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA) before the age of 18 years. There have been no comprehensive long-term studies of this rare disease, which can be associated to various immunopathological manifestations (IMs). We report outcomes of the 151 patients with pES and more than 5 years of follow-up from the nationwide French prospective OBS'CEREVANCE cohort. Median age at final follow-up was 18.5 (6.8-50.0) years and the median follow-up period was 11.3 (5.1-38.0) years. At 10 years, ITP and AIHA were in sustained complete remission in 54.5% and 78.4% of patients, respectively. The frequency and number of clinical and biological IMs increased with age: at 20 years old, 74% had at least one clinical cIM. A wide range of cIMs occurred, mainly lymphoproliferation, dermatological, gastrointestinal/hepatic and pneumological IMs. The number of cIMs was associated with a subsequent increase in the number of second-line treatments received (other than steroids and immunoglobulins; hazard ratio, 1.4; 95% confidence interval, 1.15-1.60; p = 0.0002, Cox proportional hazards method). Survival at 15 years after diagnosis was 84%. Death occurred at a median age of 18 (1.7-31.5) years, and the most frequent cause was infection. The number of second-line treatments and severe/recurrent infections were independently associated with mortality. In conclusion, longterm outcomes of pES showed remission of cytopenias but frequent IMs linked to high secondline treatment burden. Mortality was associated to drugs and/or underlying immunodeficiencies, and adolescents-young adults are a high-risk subgroup.

3.
Crit Rev Clin Lab Sci ; : 1-30, 2020 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-33356695

RESUMO

Apoptosis plays an important role in controlling the adaptive immune response and general homeostasis of the immune cells, and impaired apoptosis in the immune system results in autoimmunity and immune dysregulation. In the last 25 years, inherited human diseases of the Fas-FasL pathway have been recognized. Autoimmune lymphoproliferative syndrome (ALPS) is an inborn error of immunity, characterized clinically by nonmalignant and noninfectious lymphoproliferation, autoimmunity, and increased risk of lymphoma due to a defect in lymphocyte apoptosis. The laboratory hallmarks of ALPS are an elevated percentage of T-cell receptor αß double negative T cells (DNTs), elevated levels of vitamin B12, soluble FasL, IL-10, IL-18 and IgG, and defective in vitro Fas-mediated apoptosis. In order of frequency, the genetic defects associated with ALPS are germinal and somatic ALPS-FAS, ALPS-FASLG, ALPS-CASP10, ALPS-FADD, and ALPS-CASP8. Partial disease penetrance and severity suggest the combination of germline and somatic FAS mutations as well as other risk factor genes. In this report, we summarize human defects of apoptosis leading to ALPS and defects that are known as ALPS-like syndromes that can be clinically similar to, but are genetically distinct from, ALPS. An efficient genetic and immunological diagnostic approach to patients suspected of having ALPS or ALPS-like syndromes is essential because this enables the establishment of specific therapeutic strategies for improving the prognosis and quality of life of patients.

4.
Stem Cell Res ; 50: 102107, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33340797

RESUMO

Mutation in STING1gene, which encodes stimulator of type I IFN gene (STING) leads to its constitutive activation and thereby to a severe vasculopathy and sometimes a lupus-like disease. We generated induced pluripotent stem cells (iPSCs) from a patient carrying a rare heterozygous variant c.463G > A (resulting in a p.V155M substitution) in STING1. Cells from this patient, which were reprogrammed by non-integrative viral transduction, had normal karyotype, expressed pluripotency markers and were able to differentiate into the three germ cell layers.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33217613

RESUMO

BACKGROUND: Gain-of-function mutations in STING1 underlie a type I interferonopathy termed SAVI (STING-associated vasculopathy with onset in infancy). This severe disease is variably characterized by early-onset systemic inflammation, skin vasculopathy and interstitial lung disease (ILD). OBJECTIVE: To describe a cohort of SAVI patients. METHODS: Assessment of clinical, radiological, and immunologic data from 21 patients (17 families). RESULTS: Patients carried heterozygous substitutions in STING1 previously described in SAVI, mainly the p.V155M. Most patients were symptomatic from infancy but late onset in adulthood occurred in one patient. Systemic inflammation, skin vasculopathy and ILD were observed in 19, 18 and 21 patients respectively. Extensive tissue loss occurred in 4 patients. Severity of ILD was highly variable with insidious progression up to end-stage respiratory failure reached at teenage in 6 patients. Lung imaging revealed early fibrotic lesions. Failure to thrive was almost constant, with severe growth failure seen in 4 patients. Seven patients presented polyarthritis and one infant mimicked a combined immune deficiency. Extended features reminiscent of other interferonopathies were also found e.g. intracranial calcification, glaucoma, glomerular nephropathy. Increased expression of interferon-stimulated genes and interferon α protein was constant. Autoantibodies were frequently found, in particular rheumatoid factor. Most patients presented with a T-cell defect, with low counts of memory CD8+ cells and impaired T-cell proliferation in response to antigens. Long-term follow-up described in 8 children confirmed the clinical benefice of ruxolitinib in SAVI unless the treatment is started early in the course of the disease underlying the need for early diagnosis. Tolerance was reasonably good. CONCLUSION: This largest worldwide cohort of SAVI patients precise core features and extends the clinical and immunological phenotype of the disease, displaying overlap with other monogenic interferonopathies.

6.
Nat Commun ; 11(1): 5341, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087723

RESUMO

Autoimmunity can occur when a checkpoint of self-tolerance fails. The study of familial autoimmune diseases can reveal pathophysiological mechanisms involved in more common autoimmune diseases. Here, by whole-exome/genome sequencing we identify heterozygous, autosomal-dominant, germline loss-of-function mutations in the SOCS1 gene in ten patients from five unrelated families with early onset autoimmune manifestations. The intracellular protein SOCS1 is known to downregulate cytokine signaling by inhibiting the JAK-STAT pathway. Accordingly, patient-derived lymphocytes exhibit increased STAT activation in vitro in response to interferon-γ, IL-2 and IL-4 that is reverted by the JAK1/JAK2 inhibitor ruxolitinib. This effect is associated with a series of in vitro and in vivo immune abnormalities consistent with lymphocyte hyperactivity. Hence, SOCS1 haploinsufficiency causes a dominantly inherited predisposition to early onset autoimmune diseases related to cytokine hypersensitivity of immune cells.


Assuntos
Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Autoimunidade/genética , Proteína 1 Supressora da Sinalização de Citocina/deficiência , Proteína 1 Supressora da Sinalização de Citocina/genética , Adolescente , Adulto , Idade de Início , Doenças Autoimunes/metabolismo , Criança , Pré-Escolar , Citocinas/metabolismo , Feminino , Haploinsuficiência , Humanos , Masculino , Modelos Moleculares , Mutação , Linhagem , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina/química , Linfócitos T/imunologia
8.
Science ; 369(6504): 718-724, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32661059

RESUMO

Coronavirus disease 2019 (COVID-19) is characterized by distinct patterns of disease progression that suggest diverse host immune responses. We performed an integrated immune analysis on a cohort of 50 COVID-19 patients with various disease severity. A distinct phenotype was observed in severe and critical patients, consisting of a highly impaired interferon (IFN) type I response (characterized by no IFN-ß and low IFN-α production and activity), which was associated with a persistent blood viral load and an exacerbated inflammatory response. Inflammation was partially driven by the transcriptional factor nuclear factor-κB and characterized by increased tumor necrosis factor-α and interleukin-6 production and signaling. These data suggest that type I IFN deficiency in the blood could be a hallmark of severe COVID-19 and provide a rationale for combined therapeutic approaches.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Interferon alfa-2/metabolismo , Interferon-alfa/metabolismo , Interferon beta/metabolismo , Pneumonia Viral/imunologia , Adulto , Idoso , Betacoronavirus/fisiologia , Infecções por Coronavirus/virologia , Estado Terminal , Estudos Transversais , Feminino , Perfilação da Expressão Gênica , Humanos , Imunidade Inata , Inflamação , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Pandemias , Pneumonia Viral/virologia , Transdução de Sinais , Subpopulações de Linfócitos T/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Carga Viral
10.
Blood ; 136(9): 1055-1066, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32518946

RESUMO

Molecular dissection of inborn errors of immunity can help to elucidate the nonredundant functions of individual genes. We studied 3 children with an immune dysregulation syndrome of susceptibility to infection, lymphadenopathy, hepatosplenomegaly, developmental delay, autoimmunity, and lymphoma of B-cell (n = 2) or T-cell (n = 1) origin. All 3 showed early autologous T-cell reconstitution following allogeneic hematopoietic stem cell transplantation. By whole-exome sequencing, we identified rare homozygous germline missense or nonsense variants in a known epigenetic regulator of gene expression: ten-eleven translocation methylcytosine dioxygenase 2 (TET2). Mutated TET2 protein was absent or enzymatically defective for 5-hydroxymethylating activity, resulting in whole-blood DNA hypermethylation. Circulating T cells showed an abnormal immunophenotype including expanded double-negative, but depleted follicular helper, T-cell compartments and impaired Fas-dependent apoptosis in 2 of 3 patients. Moreover, TET2-deficient B cells showed defective class-switch recombination. The hematopoietic potential of patient-derived induced pluripotent stem cells was skewed toward the myeloid lineage. These are the first reported cases of autosomal-recessive germline TET2 deficiency in humans, causing clinically significant immunodeficiency and an autoimmune lymphoproliferative syndrome with marked predisposition to lymphoma. This disease phenotype demonstrates the broad role of TET2 within the human immune system.

11.
Artigo em Inglês | MEDLINE | ID: mdl-32499327

RESUMO

OBJECTIVE: To describe the clinical and radiologic neurologic characteristics of patients with cytotoxic T-lymphocyte antigen-4 (CTLA4) haploinsufficiency. METHODS: Three patients from 2 families had neurologic manifestations in the context of CTLA4 haploinsufficiency. Their clinical and MRI findings are presented. RESULTS: A 16-year-old boy with a previous diagnosis of combined immunodeficiency presented with severe recurrent episodes of headaches, motor deficit, and seizures associated with waxing and waning gadolinium-enhancing FLAIR cortical/juxtacortical hyperintensities. His sister, who also had combined immunodeficiency, had a brain MRI when she was aged 13 years due to recent headaches and transient right hemianopsia. It revealed a gadolinium-enhancing left occipital white matter hyperintensity. Another 49-year-old woman had progressive visual loss and cerebellar ataxia in the context of recurrent pulmonary infections. All 3 patients were found to have inherited CTLA4 haploinsufficiency. Patient 1's general condition and neurologic manifestations were completely controlled with abatacept (CTLA4-Ig). CONCLUSIONS: These cases suggest that in addition to the variable clinical penetrance and wide spectrum of CTLA4 haploinsufficiency, its neurologic spectrum is broad, ranging from recurrent tumefactive lesions to progressive deficits including cerebellar ataxia and optic atrophy with leukoencephalopathy. These phenotypes must be recognized, and should lead to a complete immunologic workup, because potentially effective targeted immunotherapy exists.

12.
Cell Rep ; 31(11): 107771, 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32553167

RESUMO

STING gain-of-function causes autoimmunity and immunodeficiency in mice and STING-associated vasculopathy with onset in infancy (SAVI) in humans. Here, we report that STING gain-of-function in mice prevents development of lymph nodes and Peyer's patches. We show that the absence of secondary lymphoid organs is associated with diminished numbers of innate lymphoid cells (ILCs), including lymphoid tissue inducer (LTi) cells. Although wild-type (WT) α4ß7+ progenitors differentiate efficiently into LTi cells, STING gain-of-function progenitors do not. Furthermore, STING gain-of-function impairs development of all types of ILCs. Patients with STING gain-of-function mutations have fewer ILCs, although they still have lymph nodes. In mice, expression of the STING mutant in RORγT-positive lineages prevents development of lymph nodes and reduces numbers of LTi cells. RORγT lineage-specific expression of STING gain-of-function also causes lung disease. Since RORγT is expressed exclusively in LTi cells during fetal development, our findings suggest that STING gain-of-function prevents lymph node organogenesis by reducing LTi cell numbers in mice.

15.
Blood Rev ; 43: 100652, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31980238

RESUMO

Juvenile myelomonocytic leukaemia (JMML) is a rare clonal disorder of early childhood. Constitutive activation of the RAS pathway is the initial event in JMML. Around 90% of patients diagnosed with JMML carry a mutation in the PTPN11, NRAS, KRAS, NF1 or CBL genes. It has been demonstrated that after this first genetic event, an additional somatic mutation or epigenetic modification is involved in disease progression. The available genetic and clinical data have enabled researchers to establish relationships between JMML and several clinical conditions, including Noonan syndrome, Ras-associated lymphoproliferative disease, and Moyamoya disease. Despite scientific progress and the development of more effective treatments, JMML is still a deadly disease: the 5-year survival rate is ~50%. Here, we report on recent research having led to a better understanding of the genetic and molecular mechanisms involved in JMML.

17.
Autoimmun Rev ; 18(10): 102361, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401343

RESUMO

Systemic lupus erythematosus (SLE) is a severe lifelong multisystem autoimmune disease characterized by the presence of autoantibodies targeting nuclear autoantigens, increased production of type I interferon and B cell abnormalities. Clinical presentation of SLE is extremely heterogeneous and different groups of disease are likely to exist. Recently, childhood-onset SLE (cSLE) cases have been linked to single gene mutations, defining the concept of monogenic or Mendelian lupus. Genes associated with Mendelian lupus can be grouped in at least three functional categories. First, complement deficiencies represent the main cause of monogenic lupus and its components are involved in the clearance of dying cells, a mechanism also called efferocytosis. Mutations in extracellular DNASE have been also identified in cSLE patients and represent additional causes leading to defective clearance of nucleic acids and apoptotic bodies. Second, the study of Aicardi-Goutières syndromes has introduced the concept of type-I interferonopathies. Bona fide lupus syndromes have been associated to this genetic condition, driven by defective nucleic acids metabolism or innate sensors overactivity. Interferon signalling anomalies can be detected and monitored during therapies, such as Janus-kinase (JAK) inhibitors. Third, tolerance breakdown can occur following genetic mutations in B and/or T cell expressing key immunoregulatory molecules. Biallelic mutations in PRKCD are associated to lupus and lymphoproliferative diseases as PKC-δ displays proapoptotic activity and is crucial to eliminate self-reactive transitional B cells. Here we review the literature of the emerging field of Mendelian lupus and discuss the physiopathological learning from these inborn errors of immunity. In addition, clinical and biological features are highlighted as well as specific therapies that have been tested in these genetic contexts.


Assuntos
Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/classificação , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Humanos , Lúpus Eritematoso Sistêmico/imunologia
19.
Blood ; 134(1): 9-21, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-30940614

RESUMO

Evans syndrome (ES) is a rare severe autoimmune disorder characterized by the combination of autoimmune hemolytic anemia and immune thrombocytopenia. In most cases, the underlying cause is unknown. We sought to identify genetic defects in pediatric ES (pES), based on a hypothesis of strong genetic determinism. In a national, prospective cohort of 203 patients with early-onset ES (median [range] age at last follow-up: 16.3 years ([1.2-41.0 years]) initiated in 2004, 80 nonselected consecutive individuals underwent genetic testing. The clinical data were analyzed as a function of the genetic findings. Fifty-two patients (65%) received a genetic diagnosis (the M+ group): 49 carried germline mutations and 3 carried somatic variants. Thirty-two (40%) had pathogenic mutations in 1 of 9 genes known to be involved in primary immunodeficiencies (TNFRSF6, CTLA4, STAT3, PIK3CD, CBL, ADAR1, LRBA, RAG1, and KRAS), whereas 20 patients (25%) carried probable pathogenic variants in 16 genes that had not previously been reported in the context of autoimmune disease. Lastly, no genetic abnormalities were found in the remaining 28 patients (35%, the M- group). The M+ group displayed more severe disease than the M- group, with a greater frequency of additional immunopathologic manifestations and a greater median number of lines of treatment. Six patients (all from the M+ group) died during the study. In conclusion, pES was potentially genetically determined in at least 65% of cases. Systematic, wide-ranging genetic screening should be offered in pES; the genetic findings have prognostic significance and may guide the choice of a targeted treatment.


Assuntos
Anemia Hemolítica Autoimune/genética , Anemia Hemolítica Autoimune/imunologia , Trombocitopenia/genética , Trombocitopenia/imunologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Mutação , Adulto Jovem
20.
J Clin Immunol ; 39(2): 171-181, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30671780

RESUMO

PURPOSE: Immune thrombocytopenic purpura (ITP) and autoimmune hemolytic anemia (AIHA) are associated in the definition of Evans syndrome (ES). The occurrence of neurological involvement in this population is poorly described and suggests an underlying primary immunodeficiency (PID). We aimed to describe the clinical manifestations, evolution, and PID profiles of these patients. METHODS: OBS'CEREVANCE is a French, nationwide prospective cohort that includes children with chronic ITP, AIHA, and ES. Patients with a neurological involvement were described. Centralized radiological and pathological reviews and genetic analyses were performed. RESULTS: On October 2016, eight patients (7/181 ES, 1/371 AIHA, and 0/615 ITP) were identified, all male, with a median age (range) at cytopenia onset of 11.5 years (1.6-15.8). Neurological symptoms appeared with a median delay of 6 years (2.5-18) after cytopenia and were polymorphic: seizures (n = 4), cranial nerve palsy (n = 2), Brown-Sequard syndrome (n = 2), intracranial pressure (n = 2), vertigo (n = 1), and/or sensory neuropathy (n = 1). Magnetic resonance imaging (MRI) showed inflammatory lesions, confirmed by pathology for five patients with macrophagic or lymphoplasmocytic infiltrates. All patients had other relevant immunopathological manifestations: pulmonary nodules (n = 6), lymphoproliferation (n = 4), abnormal immunophenotype (n = 8), and hypogammaglobulinemia (n = 7). Treatment consisted of steroids that improved symptomatology and MRI. Five patients relapsed and three had an asymptomatic radiological progression. A PID was identified in 3/8 patients: 22q11.2 microdeletion (n = 1) and CTLA deficiency (n = 2). CONCLUSION: Neurological involvement is a rare and severe late event in the course of childhood ES, which can reveal an underlying PID. Imaging and pathology examination highlight a causative immune dysregulation that may guide targeted therapeutic strategies.


Assuntos
Anemia Hemolítica Autoimune , Doenças do Sistema Nervoso , Doenças da Imunodeficiência Primária , Púrpura Trombocitopênica Idiopática , Trombocitopenia , Adolescente , Anemia Hemolítica Autoimune/diagnóstico , Anemia Hemolítica Autoimune/tratamento farmacológico , Criança , Pré-Escolar , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/tratamento farmacológico , Doenças da Imunodeficiência Primária/diagnóstico , Doenças da Imunodeficiência Primária/tratamento farmacológico , Púrpura Trombocitopênica Idiopática/diagnóstico , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Esteroides/uso terapêutico , Trombocitopenia/diagnóstico , Trombocitopenia/tratamento farmacológico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...