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1.
Nat Immunol ; 19(9): 973-985, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30127434

RESUMEN

Human inborn errors of IFN-γ immunity underlie mycobacterial diseases. We describe patients with Mycobacterium bovis (BCG) disease who are homozygous for loss-of-function mutations of SPPL2A. This gene encodes a transmembrane protease that degrades the N-terminal fragment (NTF) of CD74 (HLA invariant chain) in antigen-presenting cells. The CD74 NTF therefore accumulates in the HLA class II+ myeloid and lymphoid cells of SPPL2a-deficient patients. This toxic fragment selectively depletes IL-12- and IL-23-producing CD1c+ conventional dendritic cells (cDC2s) and their circulating progenitors. Moreover, SPPL2a-deficient memory TH1* cells selectively fail to produce IFN-γ when stimulated with mycobacterial antigens in vitro. Finally, Sppl2a-/- mice lack cDC2s, have CD4+ T cells that produce small amounts of IFN-γ after BCG infection, and are highly susceptible to infection with BCG or Mycobacterium tuberculosis. These findings suggest that inherited SPPL2a deficiency in humans underlies mycobacterial disease by decreasing the numbers of cDC2s and impairing IFN-γ production by mycobacterium-specific memory TH1* cells.


Asunto(s)
Ácido Aspártico Endopeptidasas/genética , Ácido Aspártico Endopeptidasas/metabolismo , Células Dendríticas/inmunología , Proteínas de la Membrana/metabolismo , Infecciones por Mycobacterium/inmunología , Mycobacterium bovis/fisiología , Mycobacterium tuberculosis/fisiología , Células TH1/inmunología , Tuberculosis/inmunología , Animales , Antígenos de Diferenciación de Linfocitos B/metabolismo , Células Cultivadas , Antígenos HLA/metabolismo , Antígenos de Histocompatibilidad Clase II/metabolismo , Humanos , Inmunidad , Memoria Inmunológica , Lactante , Interferón gamma/metabolismo , Linfadenopatía , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mutación/genética , Infecciones por Mycobacterium/genética , Vacunación
2.
J Gastroenterol Hepatol ; 37(6): 973-982, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35384041

RESUMEN

BACKGROUND AND AIM: Humans with inborn errors of immunity (IEI), or primary immunodeficiencies, may be associated with a potential risk factor for early-onset gastrointestinal (GI) cancer. METHODS: We systematically reviewed all cases with clinical diagnoses of both an IEI and a GI cancer in three databases (MEDLINE, SCOPUS, and EMBASE). In total, 76 publications satisfying our inclusion criteria were identified, and data for 149 cases were analyzed. We also searched our institutional cancer registry for such cases. RESULTS: We identified 149 patients with both an IEI and a GI cancer, 95 presented gastric cancer, 13 small bowel cancer, 35 colorectal cancer, and 6 had an unspecified cancer or cancer at another site. Gastric and colon adenocarcinomas were the most common. For both gastric and colorectal cancers, age at onset was significantly earlier in patients with IEIs than in the general population, based on the SEER database. Common variable immunodeficiency (CVID) was the most common IEI associated with gastrointestinal cancer. About 12% of patients had molecular genetic diagnoses, the three most frequently implicated genes being ATM, CARMIL2, and CTLA4. Impaired humoral immunity and Epstein-Barr virus (EBV) infection were frequently reported as factors potentially underlying early-onset GI cancers in patients with IEIs. We identified one patient with CVID and early-onset gastric adenocarcinoma, recurrent diarrhea, and gastrointestinal CMV infection from a retrospective survey. CONCLUSION: Patients with IEIs should be considered at risk of early-onset GI cancers and should therefore undergo cancer screening at an earlier age.


Asunto(s)
Infecciones por Virus de Epstein-Barr , Neoplasias Gastrointestinales , Neoplasias Gástricas , Infecciones por Virus de Epstein-Barr/complicaciones , Neoplasias Gastrointestinales/epidemiología , Herpesvirus Humano 4 , Humanos , Inmunogenética , Estudios Retrospectivos , Neoplasias Gástricas/epidemiología
3.
Proc Natl Acad Sci U S A ; 116(33): 16463-16472, 2019 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-31346092

RESUMEN

Heterozygous in-frame mutations in coding regions of human STAT3 underlie the only known autosomal dominant form of hyper IgE syndrome (AD HIES). About 5% of familial cases remain unexplained. The mutant proteins are loss-of-function and dominant-negative when tested following overproduction in recipient cells. However, the production of mutant proteins has not been detected and quantified in the cells of heterozygous patients. We report a deep intronic heterozygous STAT3 mutation, c.1282-89C>T, in 7 relatives with AD HIES. This mutation creates a new exon in the STAT3 complementary DNA, which, when overexpressed, generates a mutant STAT3 protein (D427ins17) that is loss-of-function and dominant-negative in terms of tyrosine phosphorylation, DNA binding, and transcriptional activity. In immortalized B cells from these patients, the D427ins17 protein was 2 kDa larger and 4-fold less abundant than wild-type STAT3, on mass spectrometry. The patients' primary B and T lymphocytes responded poorly to STAT3-dependent cytokines. These findings are reminiscent of the impaired responses of leukocytes from other patients with AD HIES due to typical STAT3 coding mutations, providing further evidence for the dominance of the mutant intronic allele. These findings highlight the importance of sequencing STAT3 introns in patients with HIES without candidate variants in coding regions and essential splice sites. They also show that AD HIES-causing STAT3 mutant alleles can be dominant-negative even if the encoded protein is produced in significantly smaller amounts than wild-type STAT3.


Asunto(s)
Proteínas de Unión al ADN/genética , Síndrome de Job/genética , Sitios de Empalme de ARN/genética , Factor de Transcripción STAT3/genética , Adulto , Alelos , Linfocitos B/metabolismo , Linfocitos B/patología , Preescolar , Exones/genética , Femenino , Regulación de la Expresión Génica/genética , Heterocigoto , Humanos , Síndrome de Job/patología , Mutación con Pérdida de Función/genética , Masculino , Persona de Mediana Edad , Linfocitos T/metabolismo , Linfocitos T/patología
4.
Genet Med ; 23(3): 576-580, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33060835

RESUMEN

PURPOSE: Rare genetic conditions like Down syndrome (DS) are historically understudied. Infection is a leading cause of mortality in DS, along with cardiac anomalies. Currently, it is unknown how the COVID-19 pandemic affects individuals with DS. Herein, we report an analysis of individuals with DS who were hospitalized with COVID-19 in New York, New York, USA. METHODS: In this retrospective, dual-center study of 7246 patients hospitalized with COVID-19, we analyzed all patients with DS admitted in the Mount Sinai Health System and Columbia University Irving Medical Center. We assessed hospitalization rates, clinical characteristics, and outcomes. RESULTS: We identified 12 patients with DS. Hospitalized individuals with DS are on average ten years younger than patients without DS. Patients with DS have more severe disease than controls, particularly an increased incidence of sepsis and mechanical ventilation. CONCLUSION: We demonstrate that individuals with DS who are hospitalized with COVID-19 are younger than their non-DS counterparts, and that they have more severe disease than age-matched controls. We conclude that particular care should be considered for both the prevention and treatment of COVID-19 in these patients.


Asunto(s)
COVID-19/patología , Síndrome de Down , Adulto , Comorbilidad , Síndrome de Down/complicaciones , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , New York/epidemiología , Pandemias , Estudios Retrospectivos
5.
Hum Mol Genet ; 27(22): 3919-3935, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31222290

RESUMEN

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.


Asunto(s)
Alelos , Codón Iniciador , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Homocigoto , Infecciones por Mycobacterium/genética , Receptores de Interferón/genética , Niño , Preescolar , Femenino , Humanos , India , Lactante , Recién Nacido , Masculino , Turquía , Secuenciación del Exoma
6.
J Clin Immunol ; 40(6): 807-819, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32572726

RESUMEN

Down syndrome (DS) is characterized by the occurrence of three copies of human chromosome 21 (HSA21). HSA21 contains a cluster of four interferon receptor (IFN-R) genes: IFNAR1, IFNAR2, IFNGR2, and IL10RB. DS patients often develop mucocutaneous infections and autoimmune diseases, mimicking patients with heterozygous gain-of-function (GOF) STAT1 mutations, which enhance cellular responses to three types of interferon (IFN). A gene dosage effect at these four loci may contribute to the infectious and autoimmune manifestations observed in individuals with DS. We report high levels of IFN-αR1, IFN-αR2, and IFN-γR2 expression on the surface of monocytes and EBV-transformed-B (EBV-B) cells from studying 45 DS patients. Total and phosphorylated STAT1 (STAT1 and pSTAT1) levels were constitutively high in unstimulated and IFN-α- and IFN-γ-stimulated monocytes from DS patients but lower than those in patients with GOF STAT1 mutations. Following stimulation with IFN-α or -γ, but not with IL-6 or IL-21, pSTAT1 and IFN-γ activation factor (GAF) DNA-binding activities were significantly higher in the EBV-B cells of DS patients than in controls. These responses resemble the dysregulated responses observed in patients with STAT1 GOF mutations. Concentrations of plasma type I IFNs were high in 12% of the DS patients tested (1.8% in the healthy controls). Levels of type I IFNs, IFN-Rs, and STAT1 were similar in DS patients with and without recurrent skin infections. We performed a genome-wide transcriptomic analysis based on principal component analysis and interferon modules on circulating monocytes. We found that DS monocytes had levels of both IFN-α- and IFN-γ-inducible ISGs intermediate to those of monocytes from healthy controls and from patients with GOF STAT1 mutations. Unlike patients with GOF STAT1 mutations, patients with DS had normal circulating Th17 counts and a high proportion of terminally differentiated CD8+ T cells with low levels of STAT1 expression. We conclude a mild interferonopathy in Down syndrome leads to an incomplete penetrance at both cellular and clinical level, which is not correlate with recurrent skin bacterial or fungal infections. The constitutive upregulation of type I and type II IFN-R, at least in monocytes of DS patients, may contribute to the autoimmune diseases observed in these individuals.


Asunto(s)
Síndrome de Down/genética , Síndrome de Down/metabolismo , Dosificación de Gen , Interferón Tipo I/metabolismo , Receptores de Interferón/genética , Adolescente , Adulto , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/patología , Linfocitos B/virología , Niño , Preescolar , Mapeo Cromosómico , Citocinas/metabolismo , Susceptibilidad a Enfermedades , Síndrome de Down/inmunología , Femenino , Perfilación de la Expresión Génica , Sitios Genéticos , Predisposición Genética a la Enfermedad , Humanos , Interferón Tipo I/genética , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Monocitos/metabolismo , Receptores de Interferón/metabolismo , Factor de Transcripción STAT1/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Transcriptoma , Adulto Joven
7.
Dig Dis Sci ; 65(4): 961-968, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31485995

RESUMEN

BACKGROUND AND AIMS: The use of anesthesia assistance (AA) for screening colonoscopy has been increasing substantially over the past decade, raising concerns about procedure safety and cost without demonstrating a proven improvement in overall quality indicators such as adenoma detection rate (ADR). The effect of AA on ADR has not been extensively studied among trainees learning colonoscopy. We aimed to determine whether type of sedation used during screening colonoscopy affects trainee ADR. METHODS: Using the electronic endoscopy databases of two hospitals in our medical center, we identified colonoscopies performed by 15 trainees from 2014 through 2018, including all screening examinations in which the cecum was reached. Multivariable logistic regression was used to determine factors associated with adenoma detection. RESULTS: We identified 1420 unique patients who underwent screening colonoscopy by a trainee meeting the inclusion criteria. Of these, 459 (32.3%) were performed with AA. Overall trainee ADR was 39.6%, with ADR increasing from 35.0% in year one of training to 42.8% in year three (p = 0.047). ADR for cases with AA was 37.9%, while ADR for conscious sedation cases was 32.0% (p = 0.374). Despite this 5.9% absolute difference, the use of AA was not associated with finding an adenoma on multivariable analysis when controlling for patient age, sex, smoking status, body mass index, trainee year of training, mean withdrawal time, supervising attending ADR, and bowel preparation quality (OR 0.85; 95% CI 0.67-1.09). CONCLUSIONS: Despite providing the ability to more consistently sedate patients, the use of AA did not affect trainee ADR. These results on trainee ADR and sedation type suggest that the overall lack of association between AA use and ADR is applicable to the trainee setting.


Asunto(s)
Adenoma/diagnóstico , Anestesia/normas , Colonoscopía/normas , Neoplasias Colorrectales/diagnóstico , Internado y Residencia/normas , Tamizaje Masivo/normas , Anciano , Anciano de 80 o más Años , Anestesia/métodos , Competencia Clínica/normas , Colonoscopía/métodos , Bases de Datos Factuales/tendencias , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/normas , Femenino , Humanos , Internado y Residencia/métodos , Masculino , Tamizaje Masivo/métodos , Persona de Mediana Edad
8.
Immunol Cell Biol ; 97(4): 360-367, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30264912

RESUMEN

Mendelian susceptibility to mycobacterial disease (MSMD) is caused by inborn errors of IFN-γ immunity. Since 1996, disease-causing mutations have been found in 11 genes, which, through allelic heterogeneity, underlie 21 different genetic disorders. We briefly review here progress in the study of molecular, cellular and clinical aspects of MSMD since the last comprehensive review published in 2014. Highlights include the discoveries of (1) a new genetic etiology, autosomal recessive signal peptide peptidase-like 2 A deficiency, (2) TYK2-deficient patients with a clinical phenotype of MSMD, (3) an allelic form of partial recessive IFN-γR2 deficiency, and (4) two forms of syndromic MSMD: RORγ/RORγT and JAK1 deficiencies. These recent findings illustrate how genetic and immunological studies of MSMD can shed a unique light onto the mechanisms of protective immunity to mycobacteria in humans.


Asunto(s)
Predisposición Genética a la Enfermedad , Infecciones por Mycobacterium/genética , Alelos , Sitios Genéticos , Geografía , Humanos , Mutación/genética
9.
Proc Natl Acad Sci U S A ; 112(44): 13615-20, 2015 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-26483451

RESUMEN

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.


Asunto(s)
Exoma , Enfermedades Genéticas Congénitas/genética , Humanos , Curva ROC
10.
J Allergy Clin Immunol ; 140(1): 232-241, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28011069

RESUMEN

BACKGROUND: Germline heterozygous mutations in human signal transducer and activator of transcription 1 (STAT1) can cause loss of function (LOF), as in patients with Mendelian susceptibility to mycobacterial diseases, or gain of function (GOF), as in patients with chronic mucocutaneous candidiasis. LOF and GOF mutations are equally rare and can affect the same domains of STAT1, especially the coiled-coil domain (CCD) and DNA-binding domain (DBD). Moreover, 6% of patients with chronic mucocutaneous candidiasis with a GOF STAT1 mutation have mycobacterial disease, obscuring the functional significance of the identified STAT1 mutations. Current computational approaches, such as combined annotation-dependent depletion, do not distinguish LOF and GOF variants. OBJECTIVE: We estimated variations in the CCD/DBD of STAT1. METHODS: We mutagenized 342 individual wild-type amino acids in the CCD/DBD (45.6% of full-length STAT1) to alanine and tested the mutants for STAT1 transcriptional activity. RESULTS: Of these 342 mutants, 201 were neutral, 30 were LOF, and 111 were GOF mutations in a luciferase assay. This assay system correctly estimated all previously reported LOF mutations (100%) and slightly fewer GOF mutations (78.1%) in the CCD/DBD of STAT1. We found that GOF alanine mutants occurred at the interface of the antiparallel STAT1 dimer, suggesting that they destabilize this dimer. This assay also precisely predicted the effect of 2 hypomorphic and dominant negative mutations, E157K and G250E, in the CCD of STAT1 that we found in 2 unrelated patients with Mendelian susceptibility to mycobacterial diseases. CONCLUSION: The systematic alanine-scanning assay is a useful tool to estimate the GOF or LOF status and the effect of heterozygous missense mutations in STAT1 identified in patients with severe infectious diseases, including mycobacterial and fungal diseases.


Asunto(s)
Alanina/genética , Infecciones por Mycobacterium/genética , Factor de Transcripción STAT1/genética , Bioensayo , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino , Mutagénesis , Mutación , Dominios Proteicos
12.
Hum Mol Genet ; 22(4): 769-81, 2013 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-23161749

RESUMEN

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.


Asunto(s)
Haploinsuficiencia , Infecciones por Mycobacterium no Tuberculosas/genética , Receptores de Interferón/genética , Adolescente , Linfocitos B/inmunología , Linfocitos B/metabolismo , Secuencia de Bases , Estudios de Casos y Controles , Células Cultivadas , Femenino , Expresión Génica , Genes Dominantes , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Interferón gamma/fisiología , Infecciones por Mycobacterium/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Linaje , Fosforilación , Procesamiento Proteico-Postraduccional , Receptores de Interferón/deficiencia , Análisis de Secuencia de ADN , Eliminación de Secuencia
14.
Blood ; 122(14): 2390-401, 2013 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-23963039

RESUMEN

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.


Asunto(s)
Deficiencias en la Proteostasis/genética , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Alcaloides/farmacología , Secuencia de Bases , Western Blotting , Niño , Inhibidores Enzimáticos/farmacología , Femenino , Citometría de Flujo , Predisposición Genética a la Enfermedad/genética , Glicosilación/efectos de los fármacos , Humanos , Masculino , Microscopía Confocal , Datos de Secuencia Molecular , Mutación , Infecciones por Mycobacterium/genética , Linaje , Transfección
15.
J Clin Immunol ; 34(8): 904-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25135595

RESUMEN

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.


Asunto(s)
Síndromes de Inmunodeficiencia/complicaciones , Síndromes de Inmunodeficiencia/genética , Infecciones por Mycobacterium/complicaciones , Infecciones por Mycobacterium/patología , Receptores de Interferón/deficiencia , Receptores de Interferón/genética , Preescolar , Resultado Fatal , Femenino , Predisposición Genética a la Enfermedad , Humanos , Síndromes de Inmunodeficiencia/inmunología , Masculino , Infecciones por Mycobacterium/inmunología , Infecciones por Mycobacterium/mortalidad
16.
N Engl J Med ; 365(2): 127-38, 2011 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-21524210

RESUMEN

BACKGROUND: The genetic analysis of human primary immunodeficiencies has defined the contribution of specific cell populations and molecular pathways in the host defense against infection. Disseminated infection caused by bacille Calmette-Guérin (BCG) vaccines is an early manifestation of primary immunodeficiencies, such as severe combined immunodeficiency. In many affected persons, the cause of disseminated BCG disease is unexplained. METHODS: We evaluated an infant presenting with features of severe immunodeficiency, including early-onset disseminated BCG disease, who required hematopoietic stem-cell transplantation. We also studied two otherwise healthy subjects with a history of disseminated but curable BCG disease in childhood. We characterized the monocyte and dendritic-cell compartments in these three subjects and sequenced candidate genes in which mutations could plausibly confer susceptibility to BCG disease. RESULTS: We detected two distinct disease-causing mutations affecting interferon regulatory factor 8 (IRF8). Both K108E and T80A mutations impair IRF8 transcriptional activity by disrupting the interaction between IRF8 and DNA. The K108E variant was associated with an autosomal recessive severe immunodeficiency with a complete lack of circulating monocytes and dendritic cells. The T80A variant was associated with an autosomal dominant, milder immunodeficiency and a selective depletion of CD11c+CD1c+ circulating dendritic cells. CONCLUSIONS: These findings define a class of human primary immunodeficiencies that affect the differentiation of mononuclear phagocytes. They also show that human IRF8 is critical for the development of monocytes and dendritic cells and for antimycobacterial immunity. (Funded by the Medical Research Council and others.).


Asunto(s)
Células Dendríticas/inmunología , Síndromes de Inmunodeficiencia/genética , Factores Reguladores del Interferón/genética , Mutación , Adolescente , Adulto , Secuencia de Aminoácidos , Animales , Células Presentadoras de Antígenos , Vacuna BCG/genética , Vacuna BCG/inmunología , Femenino , Genes Dominantes , Humanos , Lactante , Factores Reguladores del Interferón/deficiencia , Interleucina-12/biosíntesis , Leucocitos Mononucleares/inmunología , Masculino , Modelos Moleculares , Infecciones por Mycobacterium/genética , Infecciones por Mycobacterium/inmunología , Linaje , Conformación Proteica , Alineación de Secuencia
17.
Biochem Biophys Res Commun ; 455(1-2): 90-7, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25451272

RESUMEN

We studied two patients from a nonconsanguineous family with life-long abnormal liver function, hepatomegaly and abnormal fatty acid profiles. Abnormal liver function, hypoglycemia and muscle weakness are observed in various genetic diseases, including medium-chain acyl-CoA dehydrogenase (MCAD) deficiency and glycogen storage diseases. The proband showed increased free fatty acids, mainly C8 and C10, resembling fatty acid oxidation disorder. However, no mutation was found in ACADM and ACADL gene. Sequencing of theamylo-alpha-1, 6-glucosidase, 4-alpha-glucanotransferase (AGL) gene showed that both patients were compound heterozygotes for c.118C > T (p.Gln40X) and c.753_756 del CAGA (p.Asp251Glufsx29), whereas their parents were each heterozygous for one of these mutations. The AGL protein was undetectable in EBV-B cells from the two patients. Transcriptome analysis demonstrated a significant different pattern of gene expression in both of patients' cells, including genes involving in the PPAR signaling pathway, fatty acid biosynthesis, lipid synthesis and visceral fat deposition and metabolic syndrome. This unique gene expression pattern is probably due to the absence of AGL, which potentially accounts for the observed clinical phenotypes of hyperlipidemia and hepatocyte steatosis in glycogen storage disease type IIIa.


Asunto(s)
Sistema de la Enzima Desramificadora del Glucógeno/genética , Enfermedad del Almacenamiento de Glucógeno Tipo III/genética , Mutación , Acil-CoA Deshidrogenasa/deficiencia , Adolescente , Células Cultivadas , Ácidos Grasos/biosíntesis , Ácidos Grasos Insaturados/biosíntesis , Expresión Génica , Enfermedad del Almacenamiento de Glucógeno Tipo III/diagnóstico , Enfermedad del Almacenamiento de Glucógeno Tipo III/metabolismo , Humanos , Errores Innatos del Metabolismo Lipídico/diagnóstico , Masculino
18.
Hum Mol Genet ; 20(8): 1509-23, 2011 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-21266457

RESUMEN

We report a series of 14 patients from 11 kindreds with recessive partial (RP)-interferon (IFN)-γR1 deficiency. The I87T mutation was found in nine homozygous patients from Chile, Portugal and Poland, and the V63G mutation was found in five homozygous patients from the Canary Islands. Founder effects accounted for the recurrence of both mutations. The most recent common ancestors of the patients with the I87T and V63G mutations probably lived 1600 (875-2950) and 500 (200-1275) years ago, respectively. The two alleles confer phenotypes that are similar but differ in terms of IFN-γR1 levels and residual response to IFN-γ. The patients suffered from bacillus Calmette-Guérin-osis (n= 6), environmental mycobacteriosis (n= 6) or tuberculosis (n= 1). One patient did not suffer from mycobacterial infections but had disseminated salmonellosis, which was also present in two other patients. Age at onset of the first environmental mycobacterial disease differed widely between patients, with a mean value of 11.25 ± 9.13 years. Thirteen patients survived until the age of 14.82 ± 11.2 years, and one patient died at the age of 7 years, 9 days after the diagnosis of long-term Mycobacterium avium infection and the initiation of antimycobacterial treatment. Up to 10 patients are currently free of infection with no prophylaxis. The clinical heterogeneity of the 14 patients was not clearly related to either IFNGR1 genotype or the resulting cellular phenotype. RP-IFN-γR1 deficiency is, thus, more common than initially thought and should be considered in both children and adults with mild or severe mycobacterial diseases.


Asunto(s)
Predisposición Genética a la Enfermedad , Infecciones por Mycobacterium/genética , Receptores de Interferón/deficiencia , Adolescente , Adulto , Secuencia de Aminoácidos , Niño , Preescolar , Femenino , Efecto Fundador , Genes Recesivos , Haplotipos , Humanos , Interferón gamma/metabolismo , Masculino , Datos de Secuencia Molecular , Monocitos/metabolismo , Mutación Missense , Infecciones por Mycobacterium/inmunología , Infecciones por Mycobacterium/microbiología , Mycobacterium avium , Mycobacterium bovis , Osteomielitis/genética , Osteomielitis/microbiología , Linaje , Fenotipo , Fosforilación , Neumonía Bacteriana/genética , Transporte de Proteínas , Receptores de Interferón/genética , Receptores de Interferón/inmunología , Factor de Transcripción STAT1/metabolismo , Salmonella , Infecciones por Salmonella/genética , Tuberculosis/genética , Tuberculosis/microbiología , Tuberculosis/mortalidad , Adulto Joven , Receptor de Interferón gamma
19.
Clin Transl Gastroenterol ; 14(12): e00639, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37753949

RESUMEN

INTRODUCTION: Persistent villous atrophy (VA) is not uncommon in celiac disease (CeD) while patients take a gluten-free diet (GFD). METHODS: We conducted a retrospective study with 122 serum samples collected from controls and patients with CeD either at the initial diagnosis or at the follow-up during endoscopy. These samples were assigned to 3 groups: nonceliac control, non-VA CeD (Marsh score 0-2), and VA CeD (Marsh score 3a-3c). We established an in-house multiplex assay to identify potential serological biomarkers for VA. We assessed autoantibodies reported to affect the small intestine, including IgA and IgG antibodies against tissue transglutaminase (tTG), interferons, villin, actin, autoimmune enteropathy-related 75 kDa antigen (AIE-75), and tryptophan hydroxylase (TPH)-1, as well as 27 cytokines. The apolipoproteins quantified included apo A1, apo B-100, and apo A4, which were produced predominantly by the intestinal epithelium or expressed specifically in villi. RESULTS: Autoantibody levels were high only for tTG antibodies, which performed well in initial CeD diagnosis, but suboptimally for VA prediction during follow-up, because 14.6% of the follow-up patients with VA had low tTG-IgA. Increasing dilution improved tTG-IgA quantification, particularly when the antibody levels were extremely high but did not significantly improve VA detection. Among those with low tTG-IgA and persistent VA, high proinflammatory cytokines were observed in 2 patients. Median low-density lipoprotein cholesterol levels were significantly lower in the VA CeD group ( P = 0.03). Apolipoprotein levels were similar in patients with and without VA but diverged between those on a GFD or not. DISCUSSION: tTG-IgA as a biomarker is suboptimal for VA prediction while on a GFD. Persistent VA is associated with low low-density lipoprotein cholesterol levels and partially related to persistent high proinflammatory cytokines.


Asunto(s)
Enfermedad Celíaca , Humanos , Estudios Retrospectivos , Transglutaminasas , Biomarcadores , Autoanticuerpos , Inmunoglobulina A , Atrofia , Citocinas , Lipoproteínas LDL , Colesterol
20.
Front Chem ; 11: 1351934, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38162393

RESUMEN

[This corrects the article DOI: 10.3389/fchem.2022.916553.].

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