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2.
Artigo em Inglês | MEDLINE | ID: mdl-33658321

RESUMO

OBJECTIVE: To determine whether adult cases of Chronic Lymphocytic Inflammation with Pontine Perivascular Enhancement Responsive to Steroids (CLIPPERS) may be related to familial hemophagocytic lymphohistiocytosis (HLH) causes, we have screened patients with adult-onset CLIPPERS for mutations in primary HLH-associated genes. METHODS: In our cohort of 36 patients fulfilling the criteria for probable or definite CLIPPERS according to the CLIPPERS-2017 criteria, we conducted a first study on 12 patients who consented to genetic testing. In these 12 patients, systemic HLH criteria were searched, and genetic analysis of 8 genes involved in primary HLH was performed. RESULTS: Four definite and 8 probable CLIPPERS were enrolled (n = 12). Mutations involved in HLH were identified in 2 definite and 2 probable CLIPPERS (4/12). Three of them had biallelic PRF1 mutations with reduced perforin expression in natural killer cells. The remaining patient had biallelic UNC13D mutations with cytotoxic lymphocyte impaired degranulation. None of the mutated patients reached the criteria for systemic HLH. During follow-up, 3 of them displayed atypical findings for CLIPPERS, including emergence of systemic non-Hodgkin lymphoma (1/3) and confluent gadolinium-enhancing lesions on brain MRI (3/3). CONCLUSIONS: In our patients presenting with adult-onset CLIPPERS, one-third have HLH gene mutations. This genetic treatable condition should be searched in patients with CLIPPERS, especially in those presenting with atypical findings.

3.
J Clin Immunol ; 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33534079

RESUMO

Phosphoglucomutase 3 (PGM3) deficiency is a rare congenital disorder of glycosylation. Most of patients with autosomal recessive hypomorphic mutations in PGM3 encoding for phosphoglucomutase 3 present with eczema, skin and lung infections, elevated serum IgE, as well as neurological and skeletal features. A few PGM3-deficient patients suffer from a more severe disease with nearly absent T cells and severe skeletal dysplasia. We performed targeted next-generation sequencing on two kindred to identify the underlying genetic etiology of a severe combined immunodeficiency with developmental defect. We report here two novel homozygous missense variants (p.Gly359Asp and p.Met423Thr) in PGM3 identified in three patients from two unrelated kindreds with severe combined immunodeficiency, neurological impairment, and skeletal dysplasia. Both variants segregated with the disease in the two families. They were predicted to be deleterious by in silico analysis. PGM3 enzymatic activity was found to be severely impaired in primary fibroblasts and Epstein-Barr virus immortalized B cells from the kindred carrying the p.Met423Thr variant. Our findings support the pathogenicity of these two novel variants in severe PGM3 deficiency.

6.
J Clin Invest ; 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33290277

RESUMO

Inborn errors of immunity cause monogenic immune dysregulatory conditions such as severe and recurrent pathogen infection, inflammation, allergy and malignancy. Somatic reversion refers to the spontaneous repair of a pathogenic germline genetic variant and has been reported to occur in a number of inborn errors of immunity with a range of impacts on clinical outcomes of these conditions. DOCK8 deficiency due to bi-allelic inactivating mutations in DOCK8 causes a combined immunodeficiency characterised by severe bacterial, viral and fungal infections, as well as allergic disease and some cancers. Here, we describe the clinical, genetic and cellular features of three patients with bi-allelic DOCK8 variants who, following somatic reversion in multiple lymphocyte subsets, exhibited improved clinical features, including complete resolution of infection and allergic disease, cure over time. Acquisition of DOCK8 expression restored defective lymphocyte signalling, survival and proliferation, as well as CD8+ T cell cytotoxicity, CD4+ T cell cytokine production, and memory B cell generation compared to typical DOCK8-deficient patients. Our temporal analysis of DOCK8-revertant and DOCK8-deficient cells within the same individual established mechanisms of clinical improvement in these patients following somatic reversion and revealed further non-redundant functions of DOCK8 in human lymphocyte biology. Lastly, our findings have significant implications for future therapeutic options for the treatment of DOCK8 deficiency.

7.
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.

8.
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
13.
Haematologica ; 105(5): 1240-1247, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31537695

RESUMO

Although studies of mixed chimerism following hematopoietic stem cell transplantation in patients with sickle cell disease (SCD) may provide insights into the engraftment needed to correct the disease and into immunological reconstitution, an extensive multilineage analysis is lacking. We analyzed chimerism simultaneously in peripheral erythroid and granulomonocytic precursors/progenitors, highly purified B and T lymphocytes, monocytes, granulocytes and red blood cells (RBC). Thirty-four patients with mixed chimerism and ≥12 months of follow-up were included. A selective advantage of donor RBC and their progenitors/precursors led to full chimerism in mature RBC (despite partial engraftment of other lineages), and resulted in the clinical control of the disease. Six patients with donor chimerism <50% had hemolysis (reticulocytosis) and higher HbS than their donor. Four of them had donor chimerism <30%, including a patient with AA donor (hemoglobin >10 g/dL) and three with AS donors (hemoglobin <10 g/dL). However, only one vaso-occlusive crisis occurred with 68.7% HbS. Except in the patients with the lowest chimerism, the donor engraftment was lower for T cells than for the other lineages. In a context of mixed chimerism after hematopoietic stem cell transplantation for SCD, myeloid (rather than T cell) engraftment was the key efficacy criterion. Results show that myeloid chimerism as low as 30% was sufficient to prevent a vaso-occlusive crisis in transplants from an AA donor but not constantly from an AS donor. However, the correction of hemolysis requires higher donor chimerism levels (i.e ≥50%) in both AA and AS recipients. In the future, this group of patients may need a different therapeutic approach.

14.
J Immunol ; 200(10): 3519-3529, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29632141

RESUMO

HIV-1 infection is associated with B cell dysregulation and dysfunction. In HIV-1-infected patients, we previously reported preservation of intestinal lymphoid structures and dendritic cell maturation pathways after early combination antiretroviral therapy (e-ART), started during the acute phase of the infection, compared with late combination antiretroviral therapy started during the chronic phase. In this study, we investigated whether the timing of combination antiretroviral therapy initiation was associated with the development of the HIV-1-specific humoral response in the gut. The results showed that e-ART was associated with higher frequencies of functional resting memory B cells in the gut. These frequencies correlated strongly with those of follicular Th cells in the gut. Importantly, frequencies of HIV-1 Env gp140-reactive B cells were higher in patients given e-ART, in whom gp140-reactive IgG production by mucosal B cells increased after stimulation. Moreover, IL-21 release by PBMCs stimulated with HIV-1 peptide pools was greater with e-ART than with late combination antiretroviral therapy. Thus, early treatment initiation helps to maintain HIV-1-reactive memory B cells in the gut as well as follicular Th cells, whose role is crucial in the development of potent affinity-matured and broadly neutralizing Abs.


Assuntos
Antirretrovirais/uso terapêutico , Linfócitos B/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Adulto , Idoso , Linfócitos B/virologia , Feminino , Humanos , Memória Imunológica/efeitos dos fármacos , Interleucinas/metabolismo , Mucosa Intestinal/virologia , Intestinos/virologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/virologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
15.
Antimicrob Agents Chemother ; 60(6): 3832-7, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27021332

RESUMO

The Xpert Carba-R kit, version 2 (v2), which has been improved for the efficient detection of blaOXA-181 and blaOXA-232 genes, was tested on a collection of 150 well-characterized enterobacterial isolates that had a reduced susceptibility to carbapenems. The performance of the Xpert Carba-R v2 was high, as it was able to detect the five major carbapenemases (NDM, VIM, IMP, KPC, and OXA-48). Thus, it is now well adapted to the carbapenemase-producing Enterobacteriaceae epidemiology of many countries worldwide.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Infecções por Enterobacteriaceae/diagnóstico , Enterobacteriaceae/genética , Plasmídeos/isolamento & purificação , Kit de Reagentes para Diagnóstico , beta-Lactamases/isolamento & purificação , Antibacterianos/farmacologia , Proteínas de Bactérias/classificação , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Expressão Gênica , Humanos , Plasmídeos/classificação , Plasmídeos/metabolismo , beta-Lactamases/classificação , beta-Lactamases/metabolismo
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