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2.
J Clin Immunol ; 38(7): 794-803, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30264381

RESUMO

PURPOSE: CARD9 deficiency is an inborn error of immunity that predisposes otherwise healthy humans to mucocutaneous and invasive fungal infections, mostly caused by Candida, but also by dermatophytes, Aspergillus, and other fungi. Phaeohyphomycosis are an emerging group of fungal infections caused by dematiaceous fungi (phaeohyphomycetes) and are being increasingly identified in patients with CARD9 deficiency. The Corynespora genus belongs to phaeohyphomycetes and only one adult patient with CARD9 deficiency has been reported to suffer from invasive disease caused by C. cassiicola. We identified a Colombian child with an early-onset, deep, and destructive mucocutaneous infection due to C. cassiicola and we searched for mutations in CARD9. METHODS: We reviewed the medical records and immunological findings in the patient. Microbiologic tests and biopsies were performed. Whole-exome sequencing (WES) was made and Sanger sequencing was used to confirm the CARD9 mutations in the patient and her family. Finally, CARD9 protein expression was evaluated in peripheral blood mononuclear cells (PBMC) by western blotting. RESULTS: The patient was affected by a large, indurated, foul-smelling, and verrucous ulcerated lesion on the left side of the face with extensive necrosis and crusting, due to a C. cassiicola infectious disease. WES led to the identification of compound heterozygous mutations in the patient consisting of the previously reported p.Q289* nonsense (c.865C > T, exon 6) mutation, and a novel deletion (c.23_29del; p.Asp8Alafs10*) leading to a frameshift and a premature stop codon in exon 2. CARD9 protein expression was absent in peripheral blood mononuclear cells from the patient. CONCLUSION: We describe here compound heterozygous loss-of-expression mutations in CARD9 leading to severe deep and destructive mucocutaneous phaeohyphomycosis due to C. cassiicola in a Colombian child.

3.
Blood ; 132(22): 2362-2374, 2018 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-30254128

RESUMO

ARPC1B is a key factor for the assembly and maintenance of the ARP2/3 complex that is involved in actin branching from an existing filament. Germline biallelic mutations in ARPC1B have been recently described in 6 patients with clinical features of combined immunodeficiency (CID), whose neutrophils and platelets but not T lymphocytes were studied. We hypothesized that ARPC1B deficiency may also lead to cytoskeleton and functional defects in T cells. We have identified biallelic mutations in ARPC1B in 6 unrelated patients with early onset disease characterized by severe infections, autoimmune manifestations, and thrombocytopenia. Immunological features included T-cell lymphopenia, low numbers of naïve T cells, and hyper-immunoglobulin E. Alteration in ARPC1B protein structure led to absent/low expression by flow cytometry and confocal microscopy. This molecular defect was associated with the inability of patient-derived T cells to extend an actin-rich lamellipodia upon T-cell receptor (TCR) stimulation and to assemble an immunological synapse. ARPC1B-deficient T cells additionally displayed impaired TCR-mediated proliferation and SDF1-α-directed migration. Gene transfer of ARPC1B in patients' T cells using a lentiviral vector restored both ARPC1B expression and T-cell proliferation in vitro. In 2 of the patients, in vivo somatic reversion restored ARPC1B expression in a fraction of lymphocytes and was associated with a skewed TCR repertoire. In 1 revertant patient, memory CD8+ T cells expressing normal levels of ARPC1B displayed improved T-cell migration. Inherited ARPC1B deficiency therefore alters T-cell cytoskeletal dynamics and functions, contributing to the clinical features of CID.

4.
J Clin Invest ; 128(9): 3957-3975, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-29969437

RESUMO

Biallelic loss-of-function (LOF) mutations of the NCF4 gene, encoding the p40phox subunit of the phagocyte NADPH oxidase, have been described in only 1 patient. We report on 24 p40phox-deficient patients from 12 additional families in 8 countries. These patients display 8 different in-frame or out-of-frame mutations of NCF4 that are homozygous in 11 of the families and compound heterozygous in another. When overexpressed in NB4 neutrophil-like cells and EBV-transformed B cells in vitro, the mutant alleles were found to be LOF, with the exception of the p.R58C and c.120_134del alleles, which were hypomorphic. Particle-induced NADPH oxidase activity was severely impaired in the patients' neutrophils, whereas PMA-induced dihydrorhodamine-1,2,3 (DHR) oxidation, which is widely used as a diagnostic test for chronic granulomatous disease (CGD), was normal or mildly impaired in the patients. Moreover, the NADPH oxidase activity of EBV-transformed B cells was also severely impaired, whereas that of mononuclear phagocytes was normal. Finally, the killing of Candida albicans and Aspergillus fumigatus hyphae by neutrophils was conserved in these patients, unlike in patients with CGD. The patients suffer from hyperinflammation and peripheral infections, but they do not have any of the invasive bacterial or fungal infections seen in CGD. Inherited p40phox deficiency underlies a distinctive condition, resembling a mild, atypical form of CGD.

6.
Hum Mol Genet ; 27(22): 3919-3935, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31222290

RESUMO

Mendelian susceptibility to mycobacterial disease (MSMD) is characterized by clinical disease caused by weakly virulent mycobacteria, such as environmental mycobacteria and Bacillus Calmette-Guérin vaccines, in otherwise healthy individuals. All known genetic etiologies disrupt interferon (IFN)-γ immunity. Germline bi-allelic mutations of IFNGR2 can underlie partial or complete forms of IFN-γ receptor 2 (IFN-γR2) deficiency. Patients with partial IFN-γR2 deficiency express a dysfunctional molecule on the cell surface. We studied three patients with MSMD from two unrelated kindreds from Turkey (P1, P2) and India (P3), by whole-exome sequencing. P1 and P2 are homozygous for a mutation of the initiation codon(c.1A>G) of IFNGR2, whereas P3 is homozygous for a mutation of the second codon (c.4delC). Overexpressed mutant alleles produce small amounts of full-length IFN-γR2 resulting in an impaired, but not abolished, response to IFN-γ. Moreover, SV40-fibroblasts of P1 and P2 responded weakly to IFN-γ, and Epstein Barr virus-transformed B cells had a barely detectable response to IFN-γ. Studies in patients' primary T cells and monocyte-derived macrophages yielded similar results. The residual expression of IFN-γR2 protein of normal molecular weight and function is due to the initiation of translation between the second and ninth non-AUG codons. We thus describe mutations of the first and second codons of IFNGR2, which define a new form of partial recessive IFN-γR2 deficiency. Residual levels of IFN-γ signaling were very low, accounting for the more severe clinical phenotype of these patients with residual expression levels of normally functional surface receptors than of patients with partial recessive IFN-γR2 deficiency due to surface-expressed dysfunctional receptors, whose residual levels of IFN-γ signaling were higher.


Assuntos
Alelos , Códon de Iniciação , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Homozigoto , Infecções por Mycobacterium/genética , Receptores de Interferon/genética , Criança , Pré-Escolar , Feminino , Humanos , Índia , Lactente , Recém-Nascido , Masculino , Turquia , Sequenciamento Completo do Exoma
7.
J Clin Immunol ; 37(7): 732-738, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28865061

RESUMO

PURPOSE: Mendelian susceptibility to mycobacterial disease is a rare clinical condition characterized by a predisposition to infectious diseases caused by poorly virulent mycobacteria. Other infections such as salmonellosis and candidiasis are also reported. The purpose of this article is to describe a young boy affected with various infectious diseases caused by Mycobacterium tuberculosis complex, Salmonella sp, Klebsiella pneumonie, Citrobacter sp., and Candida sp, complicated with severe enteropathy and transient hypogammaglobulinemia. METHODS: We reviewed medical records and performed flow cytometry staining for lymphocyte populations, lymphocyte proliferation in response to PHA, and intracellular IFN-γ production in T cell PHA blasts in the patient and a healthy control. Sanger sequencing was used to confirm the genetic variants in the patient and relatives. RESULTS: Genetic analysis revealed a bi-allelic mutation in IL12RB1 (C291Y) resulting in complete IL-12Rß1 deficiency. Functional analysis demonstrated the lack of intracellular production of IFN-γ in CD3+ T lymphocytes from the patient in response to rhIL-12p70. CONCLUSIONS: To our knowledge, this is the third patient with MSMD due to IL-12Rß1 deficiency complicated with enteropathy and hypogammaglobulinemia and the first case of this disease to be described in Colombia.


Assuntos
Agamaglobulinemia/genética , Candidíase/genética , Enterite/genética , Infecções por Bactérias Gram-Negativas/genética , Receptores de Interleucina-12/deficiência , Receptores de Interleucina-12/genética , Agamaglobulinemia/tratamento farmacológico , Vacina BCG , Candidíase/tratamento farmacológico , Farmacorresistência Bacteriana , Enterite/tratamento farmacológico , Predisposição Genética para Doença , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Lactente , Mutação , Mycobacterium tuberculosis
8.
Rev. neurol. (Ed. impr.) ; 64(11): 481-488, 1 jun., 2017. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-163769

RESUMO

Introducción. El síndrome de Ritscher-Schinzel (también conocido como displasia cráneo-cerebelo-cardíaca o síndrome 3C) es un síndrome genético raro que se caracteriza principalmente por la asociación de anomalías cardíacas, craneofaciales y de la fosa posterior. Pacientes y métodos. Se describen 26 pacientes con síndrome de Ritscher-Schinzel pertenecientes a un hospital de Medellín en el departamento de Antioquia, Colombia. Resultados. La presente cohorte está compuesta en un 69% por hombres. La mediana de edad de la cohorte fue de 30 meses y el 42% tenía menos de 1 año de edad en el momento del diagnóstico. Todos presentaban afectación ocular, y la megalocórnea fue la manifestación ocular más frecuente (69%), mientras que las orejas de implantación baja (80,7%) y los defectos cardíacos septales (68,7%) fueron las malformaciones faciales y cardíacas más comunes, respectivamente. Las malformaciones de la fosa posterior más frecuentes fueron megacisterna magna (31,8%) y malformación de Dandy-Walker (27%). El 84% tenía retraso del neurodesarrollo o discapacidad intelectual. Las manifestaciones esqueléticas fueron frecuentes: el conjunto de camptodactilia, pliegue palmar único, dedos sobrelapados, astrágalo vertical e hipoplasia ungueal en las manos y los pies se halló en el 96% de los casos. Conclusiones. El síndrome de Ritscher-Schinzel es heterogéneo desde el punto de vista genético y clínico. Estos resultados sugieren que las anormalidades esqueléticas y oculares observadas pueden facilitar el diagnóstico fenotípico. No obstante, es necesario realizar estudios adicionales que permitan conocer mejor su prevalencia y facilitar la identificación de otros genes implicados en este síndrome (AU)


Introduction. Ritscher-Schinzel syndrome (also known as cranio-cerebello-cardiac dysplasia or 3C syndrome) is a rare genetic syndrome that is mainly characterised by the association of cardiac and craniofacial anomalies together with others affecting the posterior fossa. Patients and methods. We report on 26 patients with Ritscher-Schinzel syndrome at a hospital in Medellín, in the Department of Antioquia, Colombia. Results. Males account for 69% of this cohort. The mean age of the cohort was 30 months, and 42% were under the age of one year at the time of diagnosis. All of them presented ocular disorders, and megalocornea was the most frequent ocular manifestation (69%), whereas low-set ears (80.7%) and septal heart defects (68.7%) were the most common facial and cardiac malformations, respectively. The most frequent malformations of the posterior fossa were megacisterna magna (31.8%) and Dandy-Walker malformation (27%). 84% of the cases had delayed neurodevelopment or intellectual disability. Skeletal manifestations were frequent: the group consisting of camptodactyly, single palmar crease, overlapping fingers, vertical talus and nail hypoplasia were found in hands and feet in 96% of the cases. Conclusions. Ritscher-Schinzel syndrome is a heterogeneous syndrome from the genetic and clinical point of view. These results suggest that the skeletal and ocular abnormalities that were observed can facilitate the phenotypic diagnosis. However, it is necessary to conduct further studies that allow us to gain a deeper knowledge of its prevalence and help identify other genes involved in this syndrome (AU)


Assuntos
Humanos , Masculino , Feminino , Lactente , Pré-Escolar , Criança , Síndrome de Dandy-Walker/complicações , Cisterna Magna/anormalidades , Córnea/anormalidades , Cardiopatias Congênitas/complicações , Fenótipo , Estudos Retrospectivos , Deficiência Intelectual/epidemiologia , Tálus/anormalidades , Anormalidades Musculoesqueléticas/epidemiologia
11.
Proc Natl Acad Sci U S A ; 112(44): 13615-20, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26483451

RESUMO

The protein-coding exome of a patient with a monogenic disease contains about 20,000 variants, only one or two of which are disease causing. We found that 58% of rare variants in the protein-coding exome of the general population are located in only 2% of the genes. Prompted by this observation, we aimed to develop a gene-level approach for predicting whether a given human protein-coding gene is likely to harbor disease-causing mutations. To this end, we derived the gene damage index (GDI): a genome-wide, gene-level metric of the mutational damage that has accumulated in the general population. We found that the GDI was correlated with selective evolutionary pressure, protein complexity, coding sequence length, and the number of paralogs. We compared GDI with the leading gene-level approaches, genic intolerance, and de novo excess, and demonstrated that GDI performed best for the detection of false positives (i.e., removing exome variants in genes irrelevant to disease), whereas genic intolerance and de novo excess performed better for the detection of true positives (i.e., assessing de novo mutations in genes likely to be disease causing). The GDI server, data, and software are freely available to noncommercial users from lab.rockefeller.edu/casanova/GDI.


Assuntos
Exoma , Doenças Genéticas Inatas/genética , Humanos , Curva ROC
12.
J Exp Med ; 212(10): 1641-62, 2015 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-26304966

RESUMO

Autosomal recessive, complete TYK2 deficiency was previously described in a patient (P1) with intracellular bacterial and viral infections and features of hyper-IgE syndrome (HIES), including atopic dermatitis, high serum IgE levels, and staphylococcal abscesses. We identified seven other TYK2-deficient patients from five families and four different ethnic groups. These patients were homozygous for one of five null mutations, different from that seen in P1. They displayed mycobacterial and/or viral infections, but no HIES. All eight TYK2-deficient patients displayed impaired but not abolished cellular responses to (a) IL-12 and IFN-α/ß, accounting for mycobacterial and viral infections, respectively; (b) IL-23, with normal proportions of circulating IL-17(+) T cells, accounting for their apparent lack of mucocutaneous candidiasis; and (c) IL-10, with no overt clinical consequences, including a lack of inflammatory bowel disease. Cellular responses to IL-21, IL-27, IFN-γ, IL-28/29 (IFN-λ), and leukemia inhibitory factor (LIF) were normal. The leukocytes and fibroblasts of all seven newly identified TYK2-deficient patients, unlike those of P1, responded normally to IL-6, possibly accounting for the lack of HIES in these patients. The expression of exogenous wild-type TYK2 or the silencing of endogenous TYK2 did not rescue IL-6 hyporesponsiveness, suggesting that this phenotype was not a consequence of the TYK2 genotype. The core clinical phenotype of TYK2 deficiency is mycobacterial and/or viral infections, caused by impaired responses to IL-12 and IFN-α/ß. Moreover, impaired IL-6 responses and HIES do not appear to be intrinsic features of TYK2 deficiency in humans.


Assuntos
Síndrome de Job/etiologia , TYK2 Quinase/deficiência , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Interferon gama/metabolismo , Interleucina-10/farmacologia , Interleucina-12/metabolismo , Interleucina-12/farmacologia , Interleucina-23/farmacologia , Interleucina-6/farmacologia , Síndrome de Job/complicações , Síndrome de Job/genética , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Masculino , Mutação , Infecções por Mycobacterium/etiologia , Linfócitos T/metabolismo , Linfócitos T/patologia , TYK2 Quinase/genética , TYK2 Quinase/metabolismo , Viroses/etiologia , Adulto Jovem
13.
J Clin Immunol ; 34(8): 904-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25135595

RESUMO

Interferon-γ receptor 2 (IFN-γR2) deficiency is a rare primary immunodeficiency characterized by predisposition to infections with weakly virulent mycobacteria, such as environmental mycobacteria and BCG vaccines. We describe here two children with IFN-γR2 deficiency, from unrelated, consanguineous kindreds of Arab and Israeli descent. The first patient was a boy who died at the age of 4.5 years, from recurrent, disseminated disease caused by Mycobacterium simiae. His IFN-γR2 defect was autosomal recessive and complete. The second patient was a girl with multiple disseminated mycobacterial infections, including infection with M. simiae. She died at the age of 5 years, a short time after the transplantation of umbilical cord blood cells from an unrelated donor. Her IFN-γR2 defect was autosomal recessive and partial. Autosomal recessive IFN-γR2 deficiency is life-threatening, even in its partial form, and genetic diagnosis and familial counseling are therefore particularly important for this condition. These two cases are the first of IFN-γR2 deficiency associated with M. simiae infection to be described.


Assuntos
Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/genética , Infecções por Mycobacterium/complicações , Infecções por Mycobacterium/patologia , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Pré-Escolar , Evolução Fatal , Feminino , Predisposição Genética para Doença , Humanos , Síndromes de Imunodeficiência/imunologia , Masculino , Infecções por Mycobacterium/imunologia , Infecções por Mycobacterium/mortalidade
14.
Blood ; 122(14): 2390-401, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23963039

RESUMO

We report a molecular study of the two known patients with autosomal recessive, partial interferon-γ receptor (IFN-γR)2 deficiency (homozygous for mutations R114C and G227R), and three novel, unrelated children, homozygous for S124F (P1) and G141R (P2 and P3). IFN-γR2 levels on the surface of the three latter patients' cells are slightly lower than those on control cells. The patients' cells also display impaired, but not abolished, response to IFN-γ. Moreover, the R114C, S124F, G141R and G227R IFNGR2 hypomorphic alleles all encode misfolded proteins with abnormal N-glycosylation. The mutants are largely retained in the endoplasmic reticulum, although a small proportion reach and function at the cell surface. Strikingly, the IFN-γ response of the patients' cells is enhanced by chemical modifiers of N-glycosylation, as previously shown for patients with gain-of-glysosylation T168N and misfolding 382-387dup null mutations. All four in-frame IFNGR2 hypomorphic mutant alleles encoding surface-expressed receptors are thus deleterious by a mechanism involving abnormal N-glycosylation and misfolding of the IFN-γR2 protein. The diagnosis of partial IFN-γR2 deficiency is clinically useful, as affected patients should be treated with IFN-γ, [corrected] unlike patients with complete IFN-γR2 deficiency. Moreover, inhibitors of glycosylation might be beneficial in patients with complete or partial IFN-γR2 deficiency due to misfolding or gain-of-glycosylation receptors.


Assuntos
Deficiências na Proteostase/genética , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Alcaloides/farmacologia , Sequência de Bases , Western Blotting , Criança , Inibidores Enzimáticos/farmacologia , Feminino , Citometria de Fluxo , Predisposição Genética para Doença/genética , Glicosilação/efeitos dos fármacos , Humanos , Masculino , Microscopia Confocal , Dados de Sequência Molecular , Mutação , Infecções por Mycobacterium/genética , Linhagem , Transfecção
15.
Hum Mol Genet ; 22(4): 769-81, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23161749

RESUMO

Mendelian susceptibility to mycobacterial diseases (MSMD) is a rare syndrome, the known genetic etiologies of which impair the production of, or the response to interferon-gamma (IFN-γ). We report here a patient (P1) with MSMD whose cells display mildly impaired responses to IFN-γ, at levels, however, similar to those from MSMD patients with autosomal recessive (AR) partial IFN-γR2 or STAT1 deficiency. Whole-exome sequencing (WES) and Sanger sequencing revealed only one candidate variation for both MSMD-causing and IFN-γ-related genes. P1 carried a heterozygous frame-shift IFNGR2 mutation inherited from her father. We show that the mutant allele is intrinsically loss-of-function and not dominant-negative, suggesting haploinsufficiency at the IFNGR2 locus. We also show that Epstein-Barr virus transformed B lymphocyte cells from 10 heterozygous relatives of patients with AR complete IFN-γR2 deficiency respond poorly to IFN-γ, in some cases as poorly as the cells of P1. Naive CD4(+) T cells and memory IL-4-producing T cells from these individuals also responded poorly to IFN-γ, whereas monocytes and monocyte-derived macrophages (MDMs) did not. This is consistent with the lower levels of expression of IFN-γR2 in lymphoid than in myeloid cells. Overall, MSMD in this patient is probably due to autosomal dominant (AD) IFN-γR2 deficiency, resulting from haploinsufficiency, at least in lymphoid cells. The clinical penetrance of AD IFN-γR2 deficiency is incomplete, possibly due, at least partly, to the variability of cellular responses to IFN-γ in these individuals.


Assuntos
Haploinsuficiência , Infecções por Micobactéria não Tuberculosa/genética , Receptores de Interferon/genética , Adolescente , Linfócitos B/imunologia , Linfócitos B/metabolismo , Sequência de Bases , Estudos de Casos e Controles , Células Cultivadas , Feminino , Expressão Gênica , Genes Dominantes , Estudos de Associação Genética , Predisposição Genética para Doença , Heterozigoto , Humanos , Interferon gama/fisiologia , Infecções por Mycobacterium/genética , Análise de Sequência com Séries de Oligonucleotídeos , Linhagem , Fosforilação , Processamento de Proteína Pós-Traducional , Receptores de Interferon/deficiência , Análise de Sequência de DNA , Deleção de Sequência
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