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1.
J Exp Med ; 216(9): 2038-2056, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31217193

RESUMO

Autosomal recessive IRF7 and IRF9 deficiencies impair type I and III IFN immunity and underlie severe influenza pneumonitis. We report three unrelated children with influenza A virus (IAV) infection manifesting as acute respiratory distress syndrome (IAV-ARDS), heterozygous for rare TLR3 variants (P554S in two patients and P680L in the third) causing autosomal dominant (AD) TLR3 deficiency. AD TLR3 deficiency can underlie herpes simplex virus-1 (HSV-1) encephalitis (HSE) by impairing cortical neuron-intrinsic type I IFN immunity to HSV-1. TLR3-mutated leukocytes produce normal levels of IFNs in response to IAV. In contrast, TLR3-mutated fibroblasts produce lower levels of IFN-ß and -λ, and display enhanced viral susceptibility, upon IAV infection. Moreover, the patients' iPSC-derived pulmonary epithelial cells (PECs) are susceptible to IAV. Treatment with IFN-α2b or IFN-λ1 rescues this phenotype. AD TLR3 deficiency may thus underlie IAV-ARDS by impairing TLR3-dependent, type I and/or III IFN-mediated, PEC-intrinsic immunity. Its clinical penetrance is incomplete for both IAV-ARDS and HSE, consistent with their typically sporadic nature.

4.
J Exp Med ; 215(9): 2289-2310, 2018 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-30068544

RESUMO

Patients with epidermodysplasia verruciformis (EV) and biallelic null mutations of TMC6 (encoding EVER1) or TMC8 (EVER2) are selectively prone to disseminated skin lesions due to keratinocyte-tropic human ß-papillomaviruses (ß-HPVs), which lack E5 and E8. We describe EV patients homozygous for null mutations of the CIB1 gene encoding calcium- and integrin-binding protein-1 (CIB1). CIB1 is strongly expressed in the skin and cultured keratinocytes of controls but not in those of patients. CIB1 forms a complex with EVER1 and EVER2, and CIB1 proteins are not expressed in EVER1- or EVER2-deficient cells. The known functions of EVER1 and EVER2 in human keratinocytes are not dependent on CIB1, and CIB1 deficiency does not impair keratinocyte adhesion or migration. In keratinocytes, the CIB1 protein interacts with the HPV E5 and E8 proteins encoded by α-HPV16 and γ-HPV4, respectively, suggesting that this protein acts as a restriction factor against HPVs. Collectively, these findings suggest that the disruption of CIB1-EVER1-EVER2-dependent keratinocyte-intrinsic immunity underlies the selective susceptibility to ß-HPVs of EV patients.

5.
PLoS Negl Trop Dis ; 12(4): e0006429, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29708969

RESUMO

Buruli ulcer (BU), the third most frequent mycobacteriosis worldwide, is a neglected tropical disease caused by Mycobacterium ulcerans. We report the clinical description and extensive genetic analysis of a consanguineous family from Benin comprising two cases of unusually severe non-ulcerative BU. The index case was the most severe of over 2,000 BU cases treated at the Centre de Dépistage et de Traitement de la Lèpre et de l'Ulcère de Buruli, Pobe, Benin, since its opening in 2003. The infection spread to all limbs with PCR-confirmed skin, bone and joint infections. Genome-wide linkage analysis of seven family members was performed and whole-exome sequencing of both patients was obtained. A 37 kilobases homozygous deletion confirmed by targeted resequencing and located within a linkage region on chromosome 8 was identified in both patients but was absent from unaffected siblings. We further assessed the presence of this deletion on genotyping data from 803 independent local individuals (402 BU cases and 401 BU-free controls). Two BU cases were predicted to be homozygous carriers while none was identified in the control group. The deleted region is located close to a cluster of beta-defensin coding genes and contains a long non-coding (linc) RNA gene previously shown to display highest expression values in the skin. This first report of a microdeletion co-segregating with severe BU in a large family supports the view of a key role of human genetics in the natural history of the disease.


Assuntos
Úlcera de Buruli/genética , Cromossomos Humanos Par 8/genética , Mycobacterium ulcerans/fisiologia , Adolescente , Benin , Úlcera de Buruli/microbiologia , Pré-Escolar , Consanguinidade , Feminino , Ligação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Linhagem , Fenótipo , Deleção de Sequência , Sequenciamento Completo do Exoma
6.
Cell ; 172(5): 952-965.e18, 2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29474921

RESUMO

Viruses that are typically benign sometimes invade the brainstem in otherwise healthy children. We report bi-allelic DBR1 mutations in unrelated patients from different ethnicities, each of whom had brainstem infection due to herpes simplex virus 1 (HSV1), influenza virus, or norovirus. DBR1 encodes the only known RNA lariat debranching enzyme. We show that DBR1 expression is ubiquitous, but strongest in the spinal cord and brainstem. We also show that all DBR1 mutant alleles are severely hypomorphic, in terms of expression and function. The fibroblasts of DBR1-mutated patients contain higher RNA lariat levels than control cells, this difference becoming even more marked during HSV1 infection. Finally, we show that the patients' fibroblasts are highly susceptible to HSV1. RNA lariat accumulation and viral susceptibility are rescued by wild-type DBR1. Autosomal recessive, partial DBR1 deficiency underlies viral infection of the brainstem in humans through the disruption of tissue-specific and cell-intrinsic immunity to viruses.

7.
J Clin Invest ; 127(9): 3543-3556, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28783042

RESUMO

Varicella zoster virus (VZV) typically causes chickenpox upon primary infection. In rare cases, VZV can give rise to life-threatening disease in otherwise healthy people, but the immunological basis for this remains unexplained. We report 4 cases of acute severe VZV infection affecting the central nervous system or the lungs in unrelated, otherwise healthy children who are heterozygous for rare missense mutations in POLR3A (one patient), POLR3C (one patient), or both (two patients). POLR3A and POLR3C encode subunits of RNA polymerase III. Leukocytes from all 4 patients tested exhibited poor IFN induction in response to synthetic or VZV-derived DNA. Moreover, leukocytes from 3 of the patients displayed defective IFN production upon VZV infection and reduced control of VZV replication. These phenotypes were rescued by transduction with relevant WT alleles. This work demonstrates that monogenic or digenic POLR3A and POLR3C deficiencies confer increased susceptibility to severe VZV disease in otherwise healthy children, providing evidence for an essential role of a DNA sensor in human immunity.


Assuntos
Varicela/genética , Herpes Zoster/genética , Mutação , RNA Polimerase III/genética , RNA Polimerase III/metabolismo , Alelos , Animais , Criança , Análise Mutacional de DNA , Regulação Enzimológica da Expressão Gênica , Células HEK293 , Herpesvirus Humano 3 , Heterozigoto , Humanos , Leucócitos/metabolismo , Camundongos , Mutação de Sentido Incorreto , Fenótipo
8.
Pediatr Infect Dis J ; 36(8): 741-744, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28471862

RESUMO

BACKGROUND: Herpes simplex encephalitis (HSE) after primary herpes simplex virus (HSV)-1 infection can occur in children due to inborn errors of cell-intrinsic immunity in the central nervous system. Paradoxically, symptomatic mucocutaneous HSV-1 recurrences are rare survivors of childhood HSE. T-cell-acquired immunity is thought to be involved in control of recurrent mucocutaneous HSV infection. We thus tested HSV-1-specific immunity in HSE survivors. METHODS: We obtained serum and peripheral blood mononuclear cells (PBMCs) from participants a median of 13.5 years after HSE. HSV-1 and HSV-2 IgG was detected by type-specific immunoblot. PBMCs from subjects passing quality control criteria were tested using enzyme-linked immunospot assay for CD4 interferon-γ responses with an HSV-1 lysate and for CD8 responses using pooled synthetic HSV-1 peptide CD8 T-cell epitopes. Healthy adult PBMCs were used to standardize assays and as comparators. RESULTS: All participants were HSV-1 seropositive. Most (23/24) HSE survivors had human leukocyte antigen class I types matching the human leukocyte antigen restriction of the pooled peptides. We detected HSV-specific CD8 T-cell responses in 14 of 24 (58%) HSE survivors and in 9 of 9 healthy HSV-1 seropositive adults. HSV-specific CD4 T-cell responses were present in all 5 HSE subjects tested and in 8 of 9 healthy adults. Response magnitudes were overlapping between subject groups. CONCLUSIONS: The defects in cell-intrinsic immunity leading to failure to control primary central nervous system HSV-1 infection do not preclude the acquisition of specific immunity or the control of recurrent mucocutaneous HSV infections. The rarity and lack of severe or recurrent mucocutaneous HSV infection in survivors of childhood HSE corresponds with intact adaptive T-cell immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Encefalite por Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Adolescente , Linfócitos T CD4-Positivos/imunologia , Criança , Pré-Escolar , Estudos de Coortes , ELISPOT , Epitopos/imunologia , Humanos , Lactente , Proteínas Virais/imunologia
9.
J Am Coll Cardiol ; 69(13): 1653-1665, 2017 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-28359509

RESUMO

BACKGROUND: Myocarditis is inflammation of the heart muscle that can follow various viral infections. Why children only rarely develop life-threatening acute viral myocarditis (AVM), given that the causal viral infections are common, is unknown. Genetic lesions might underlie such susceptibilities. Mouse genetic studies demonstrated that interferon (IFN)-α/ß immunity defects increased susceptibility to virus-induced myocarditis. Moreover, variations in human TLR3, a potent inducer of IFNs, were proposed to underlie AVM. OBJECTIVES: This study sought to evaluate the hypothesis that human genetic factors may underlie AVM in previously healthy children. METHODS: We tested the role of TLR3-IFN immunity using human induced pluripotent stem cell-derived cardiomyocytes. We then performed whole-exome sequencing of 42 unrelated children with acute myocarditis (AM), some with proven viral causes. RESULTS: We found that TLR3- and STAT1-deficient cardiomyocytes were not more susceptible to Coxsackie virus B3 (CVB3) infection than control cells. Moreover, CVB3 did not induce IFN-α/ß and IFN-α/ß-stimulated genes in control cardiomyocytes. Finally, exogenous IFN-α did not substantially protect cardiomyocytes against CVB3. We did not observe a significant enrichment of rare variations in TLR3- or IFN-α/ß-related genes. Surprisingly, we found that homozygous but not heterozygous rare variants in genes associated with inherited cardiomyopathies were significantly enriched in AM-AVM patients compared with healthy individuals (p = 2.22E-03) or patients with other diseases (p = 1.08E-04). Seven of 42 patients (16.7%) carried rare biallelic (homozygous or compound heterozygous) nonsynonymous or splice-site variations in 6 cardiomyopathy-associated genes (BAG3, DSP, PKP2, RYR2, SCN5A, or TNNI3). CONCLUSIONS: Previously silent recessive defects of the myocardium may predispose to acute heart failure presenting as AM, notably after common viral infections in children.


Assuntos
Cardiomiopatias/genética , Enterovirus Humano B/fisiologia , Miocardite/genética , Fator de Transcrição STAT1/genética , Receptor 3 Toll-Like/genética , Cardiomiopatias/complicações , Estudos de Casos e Controles , Feminino , Interações Hospedeiro-Patógeno/genética , Humanos , Células-Tronco Pluripotentes Induzidas , Masculino , Miocardite/virologia , Miócitos Cardíacos/virologia
10.
J Clin Invest ; 127(5): 1991-2006, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28414293

RESUMO

Inborn errors of DNA repair or replication underlie a variety of clinical phenotypes. We studied 5 patients from 4 kindreds, all of whom displayed intrauterine growth retardation, chronic neutropenia, and NK cell deficiency. Four of the 5 patients also had postnatal growth retardation. The association of neutropenia and NK cell deficiency, which is unusual among primary immunodeficiencies and bone marrow failures, was due to a blockade in the bone marrow and was mildly symptomatic. We discovered compound heterozygous rare mutations in Go-Ichi-Ni-San (GINS) complex subunit 1 (GINS1, also known as PSF1) in the 5 patients. The GINS complex is essential for eukaryotic DNA replication, and homozygous null mutations of GINS component-encoding genes are embryonic lethal in mice. The patients' fibroblasts displayed impaired GINS complex assembly, basal replication stress, impaired checkpoint signaling, defective cell cycle control, and genomic instability, which was rescued by WT GINS1. The residual levels of GINS1 activity reached 3% to 16% in patients' cells, depending on their GINS1 genotype, and correlated with the severity of growth retardation and the in vitro cellular phenotype. The levels of GINS1 activity did not influence the immunological phenotype, which was uniform. Autosomal recessive, partial GINS1 deficiency impairs DNA replication and underlies intra-uterine (and postnatal) growth retardation, chronic neutropenia, and NK cell deficiency.


Assuntos
Proteínas de Ligação a DNA/deficiência , Doenças Genéticas Inatas , Transtornos do Crescimento , Síndromes de Imunodeficiência , Células Matadoras Naturais , Neutropenia , Animais , Proteínas de Ligação a DNA/imunologia , Feminino , Retardo do Crescimento Fetal/genética , Retardo do Crescimento Fetal/imunologia , Doenças Genéticas Inatas/genética , Doenças Genéticas Inatas/imunologia , Transtornos do Crescimento/genética , Transtornos do Crescimento/imunologia , Humanos , Síndromes de Imunodeficiência/genética , Síndromes de Imunodeficiência/imunologia , Lactente , Masculino , Camundongos , Neutropenia/genética , Neutropenia/imunologia
11.
Cell ; 168(5): 789-800.e10, 2017 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-28235196

RESUMO

The molecular basis of the incomplete penetrance of monogenic disorders is unclear. We describe here eight related individuals with autosomal recessive TIRAP deficiency. Life-threatening staphylococcal disease occurred during childhood in the proband, but not in the other seven homozygotes. Responses to all Toll-like receptor 1/2 (TLR1/2), TLR2/6, and TLR4 agonists were impaired in the fibroblasts and leukocytes of all TIRAP-deficient individuals. However, the whole-blood response to the TLR2/6 agonist staphylococcal lipoteichoic acid (LTA) was abolished only in the index case individual, the only family member lacking LTA-specific antibodies (Abs). This defective response was reversed in the patient, but not in interleukin-1 receptor-associated kinase 4 (IRAK-4)-deficient individuals, by anti-LTA monoclonal antibody (mAb). Anti-LTA mAb also rescued the macrophage response in mice lacking TIRAP, but not TLR2 or MyD88. Thus, acquired anti-LTA Abs rescue TLR2-dependent immunity to staphylococcal LTA in individuals with inherited TIRAP deficiency, accounting for incomplete penetrance. Combined TIRAP and anti-LTA Ab deficiencies underlie staphylococcal disease in this patient.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Lipopolissacarídeos/metabolismo , Glicoproteínas de Membrana/deficiência , Receptores de Interleucina-1/deficiência , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/imunologia , Ácidos Teicoicos/metabolismo , Imunidade Adaptativa , Criança , Feminino , Fibroblastos/metabolismo , Humanos , Imunidade Inata , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Masculino , Glicoproteínas de Membrana/análise , Glicoproteínas de Membrana/genética , Monócitos/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Linhagem , Fagócitos/metabolismo , Mutação Puntual , Isoformas de Proteínas/análise , Isoformas de Proteínas/genética , Receptores de Interleucina-1/análise , Receptores de Interleucina-1/genética , Infecções Estafilocócicas/tratamento farmacológico , Ácidos Teicoicos/imunologia , Receptor 2 Toll-Like/metabolismo , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo
12.
J Exp Med ; 213(11): 2413-2435, 2016 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-27647349

RESUMO

Combined immunodeficiency (CID) refers to inborn errors of human T cells that also affect B cells because of the T cell deficit or an additional B cell-intrinsic deficit. In this study, we report six patients from three unrelated families with biallelic loss-of-function mutations in RLTPR, the mouse orthologue of which is essential for CD28 signaling. The patients have cutaneous and pulmonary allergy, as well as a variety of bacterial and fungal infectious diseases, including invasive tuberculosis and mucocutaneous candidiasis. Proportions of circulating regulatory T cells and memory CD4+ T cells are reduced. Their CD4+ T cells do not respond to CD28 stimulation. Their CD4+ T cells exhibit a "Th2" cell bias ex vivo and when cultured in vitro, contrasting with the paucity of "Th1," "Th17," and T follicular helper cells. The patients also display few memory B cells and poor antibody responses. This B cell phenotype does not result solely from the T cell deficiency, as the patients' B cells fail to activate NF-κB upon B cell receptor (BCR) stimulation. Human RLTPR deficiency is a CID affecting at least the CD28-responsive pathway in T cells and the BCR-responsive pathway in B cells.


Assuntos
Alelos , Linfócitos B/imunologia , Proteínas dos Microfilamentos/genética , Mutação/genética , Linfócitos T/imunologia , Adolescente , Adulto , Sequência de Bases , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/imunologia , Diferenciação Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Criança , Pré-Escolar , Dimerização , Feminino , Células HEK293 , Humanos , Memória Imunológica , Imunofenotipagem , Leucócitos/patologia , Masculino , NF-kappa B/metabolismo , Linhagem , Fenótipo , Receptores de Antígenos de Linfócitos B , Transdução de Sinais , Células Th17/imunologia , Células Th2/imunologia , Adulto Jovem
13.
J Clin Immunol ; 36(1): 19-27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26686525

RESUMO

Collagen and calcium-binding EGF domain-containing protein 1 (CCBE1) bi-allelic mutations have been associated with syndromes of widespread congenital lymphatic dysplasia, including Hennekam Syndrome (HS). HS is characterized by lymphedema, lymphangiectasia, and intellectual disability. CCBE1 encodes a putative extracellular matrix protein but the HS-causing mutations have not been studied biochemically. We report two HS siblings, born to consanguineous parents of Turkish ancestry, whose clinical phenotype also includes protein losing enteropathy, painful relapsing chylous ascites, and hypogammaglobulinemia. We identified by whole exome and Sanger sequencing the homozygous CCBE1 C174Y mutation in both siblings. This mutation had been previously reported in another HS kindred from the Netherlands. In over-expression studies, we found increased intracellular expression of all forms (monomers, dimers, trimers) of the CCBE1 C174Y mutant protein, by Western blot, despite mutant mRNA levels similar to wild-type (WT). In addition, we detected increased secretion of the mutant CCBE1 protein by ELISA. We further found the mutant and WT proteins to be evenly distributed in the cytoplasm, by immunofluorescence and confocal microscopy. Finally, we found a strong decrease of lymphatic vessels, with a corresponding diminished expression of CCBE1, by immunohistochemistry of the patients' intestinal biopsies. In contrast, mucosal blood vessels and muscularis mucosae showed normal CCBE1 staining. Our findings show that the mutant CCBE1 C174Y protein is not loss-of-function by loss-of-expression.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Anormalidades Craniofaciais/diagnóstico , Linfangiectasia Intestinal/diagnóstico , Linfedema/diagnóstico , Proteínas Supressoras de Tumor/metabolismo , Adulto , Proteínas de Ligação ao Cálcio/genética , Consanguinidade , Anormalidades Craniofaciais/genética , Análise Mutacional de DNA , Feminino , Regulação da Expressão Gênica/genética , Homozigoto , Humanos , Linfangiectasia Intestinal/genética , Linfedema/genética , Masculino , Mutação/genética , Linhagem , Irmãos , Proteínas Supressoras de Tumor/genética , Turquia , Adulto Jovem
14.
Science ; 348(6233): 448-53, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25814066

RESUMO

Severe influenza disease strikes otherwise healthy children and remains unexplained. We report compound heterozygous null mutations in IRF7, which encodes the transcription factor interferon regulatory factor 7, in an otherwise healthy child who suffered life-threatening influenza during primary infection. In response to influenza virus, the patient's leukocytes and plasmacytoid dendritic cells produced very little type I and III interferons (IFNs). Moreover, the patient's dermal fibroblasts and induced pluripotent stem cell (iPSC)-derived pulmonary epithelial cells produced reduced amounts of type I IFN and displayed increased influenza virus replication. These findings suggest that IRF7-dependent amplification of type I and III IFNs is required for protection against primary infection by influenza virus in humans. They also show that severe influenza may result from single-gene inborn errors of immunity.


Assuntos
Heterozigoto , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/imunologia , Fator Regulador 7 de Interferon/genética , Interferon Tipo I/biossíntese , Síndrome do Desconforto Respiratório do Adulto/imunologia , Criança , Células Dendríticas/imunologia , Feminino , Fibroblastos/imunologia , Genes Recessivos , Humanos , Células-Tronco Pluripotentes Induzidas/imunologia , Influenza Humana/complicações , Influenza Humana/genética , Interferon Tipo I/genética , Leucócitos/imunologia , Pulmão/imunologia , Mutação , Síndrome do Desconforto Respiratório do Adulto/genética , Síndrome do Desconforto Respiratório do Adulto/virologia , Mucosa Respiratória/imunologia
15.
Neurology ; 83(21): 1888-97, 2014 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-25339207

RESUMO

OBJECTIVE: To determine the proportion of children with herpes simplex encephalitis (HSE) displaying TLR3 deficiency, the extent of TLR3 allelic heterogeneity, and the specific clinical features of TLR3 deficiency. METHODS: We determined the sequence of all exons of TLR3 in 110 of the 120 patients with HSE enrolled in our study who do not carry any of the previously described HSE-predisposing mutations of TLR3 pathway genes (TLR3, UNC93B1, TRIF, TRAF3, and TBK1). All the new mutant TLR3 alleles detected were characterized experimentally in-depth to establish the causal relationship between the genotype and phenotype. RESULTS: In addition to the 3 previously reported TLR3-deficient patients from the same cohort, 6 other children or young adults with HSE carry 1 of 5 unique or extremely rare (minor allele frequency <0.001) missense TLR3 alleles. Two alleles (M374T, D592N) heterozygous in 3 patients are not deleterious in vitro. The other 3 are deleterious via different mechanisms: G743D+R811I and L360P heterozygous in 2 patients are loss-of-function due to low levels of expression and lack of cleavage, respectively, and R867Q homozygous in 1 patient is hypomorphic. The 3 patients' fibroblasts display impaired TLR3 responses and enhanced herpes simplex virus 1 susceptibility. Overall, TLR3 deficiency is therefore found in 6 (5%) of the 120 patients studied. There is high allelic heterogeneity, with 3 forms of autosomal dominant partial defect by negative dominance or haploinsufficiency, and 2 forms of autosomal recessive defect with complete or partial deficiency. Finally, 4 (66%) of the 6 TLR3-deficient patients had at least 1 late relapse of HSE, whereas relapse occurred in only 12 (10%) of the total cohort of 120 patients. CONCLUSIONS: Childhood-onset HSE is due to TLR3 deficiency in a traceable fraction of patients, in particular the ones with HSE recurrence. Mutations in TLR3 and TLR3 pathway genes should be searched and experimentally studied in children with HSE, and patients with proven TLR3 deficiency should be followed carefully.


Assuntos
Encefalite por Herpes Simples/diagnóstico , Encefalite por Herpes Simples/genética , Frequência do Gene/genética , Mutação/genética , Receptor 3 Toll-Like/deficiência , Receptor 3 Toll-Like/genética , Adolescente , Células Cultivadas , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Linhagem , Recidiva , Fatores de Risco
16.
J Exp Med ; 210(9): 1743-59, 2013 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-23897980

RESUMO

Kaposi sarcoma (KS), a human herpes virus 8 (HHV-8; also called KSHV)-induced endothelial tumor, develops only in a small fraction of individuals infected with HHV-8. We hypothesized that inborn errors of immunity to HHV-8 might underlie the exceedingly rare development of classic KS in childhood. We report here autosomal recessive OX40 deficiency in an otherwise healthy adult with childhood-onset classic KS. OX40 is a co-stimulatory receptor expressed on activated T cells. Its ligand, OX40L, is expressed on various cell types, including endothelial cells. We found OX40L was abundantly expressed in KS lesions. The mutant OX40 protein was poorly expressed on the cell surface and failed to bind OX40L, resulting in complete functional OX40 deficiency. The patient had a low proportion of effector memory CD4(+) T cells in the peripheral blood, consistent with impaired CD4(+) T cell responses to recall antigens in vitro. The proportion of effector memory CD8(+) T cells was less diminished. The proportion of circulating memory B cells was low, but the antibody response in vivo was intact, including the response to a vaccine boost. Together, these findings suggest that human OX40 is necessary for robust CD4(+) T cell memory and confers apparently selective protective immunity against HHV-8 infection in endothelial cells.


Assuntos
Padrões de Herança/genética , Receptores OX40/deficiência , Receptores OX40/genética , Sarcoma de Kaposi/genética , Adulto , Idade de Início , Sequência de Aminoácidos , Substituição de Aminoácidos/genética , Formação de Anticorpos/imunologia , Sequência de Bases , Membrana Celular/metabolismo , Criança , Cisteína/genética , Feminino , Células HEK293 , Homozigoto , Humanos , Memória Imunológica/imunologia , Espaço Intracelular/metabolismo , Contagem de Linfócitos , Dados de Sequência Molecular , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutação/genética , Receptores OX40/química , Receptores OX40/metabolismo , Sarcoma de Kaposi/sangue , Sarcoma de Kaposi/imunologia , Sarcoma de Kaposi/patologia , Subpopulações de Linfócitos T/metabolismo , Adulto Jovem
17.
J Allergy Clin Immunol ; 131(4): 1157-66, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23434283

RESUMO

BACKGROUND: Inborn errors in Toll-like receptor 3 (TLR3)-IFN type I and III pathways have been implicated in susceptibility to herpes simplex virus encephalitis (HSE) in children, but most patients studied do not carry mutations in any of the genes presently associated with HSE susceptibility. Moreover, many patients do not display any TLR3-IFN-related fibroblastic phenotype. OBJECTIVE: To study other signaling pathways downstream of TLR3 and/or other independent pathways that may contribute to HSE susceptibility. METHODS: We used the stable isotope labeling of amino acids in cell culture proteomics methodology to measure changes in the human immortalized fibroblast proteome after TLR3 activation. RESULTS: Cells from healthy controls were compared with cells from a patient with a known genetic etiology of HSE (UNC-93B-/-) and also to cells from an HSE patient with an unknown gene defect. Consistent with known variation in susceptibility of individuals to viral infections, substantial variation in the response level of different healthy controls was observed, but common functional networks could be identified, including upregulation of superoxide dismutase 2. The 2 patients with HSE studied show clear differences in functional response networks when compared with healthy controls and also when compared with each other. CONCLUSIONS: The present study delineates a number of novel proteins, TLR3-related pathways, and cellular phenotypes that may help elucidate the genetic basis of childhood HSE. Furthermore, our results reveal superoxide dismutase 2 as a potential therapeutic target for amelioration of the neurologic sequelae caused by HSE.


Assuntos
Encefalite por Herpes Simples/genética , Fibroblastos/imunologia , Regulação da Expressão Gênica , Proteoma/genética , Superóxido Dismutase/genética , Receptor 3 Toll-Like/genética , Criança , Encefalite por Herpes Simples/imunologia , Encefalite por Herpes Simples/patologia , Fibroblastos/patologia , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Proteoma/imunologia , Transdução de Sinais , Superóxido Dismutase/imunologia , Receptor 3 Toll-Like/imunologia
18.
J Exp Med ; 209(9): 1567-82, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-22851595

RESUMO

Childhood herpes simplex virus-1 (HSV-1) encephalitis (HSE) may result from single-gene inborn errors of TLR3 immunity. TLR3-dependent induction of IFN-α/ß or IFN-λ is crucial for protective immunity against primary HSV-1 infection in the central nervous system (CNS). We describe here two unrelated children with HSE carrying different heterozygous mutations (D50A and G159A) in TBK1, the gene encoding TANK-binding kinase 1, a kinase at the crossroads of multiple IFN-inducing signaling pathways. Both mutant TBK1 alleles are loss-of-function but through different mechanisms: protein instability (D50A) or a loss of kinase activity (G159A). Both are also associated with an autosomal-dominant (AD) trait but by different mechanisms: haplotype insufficiency (D50A) or negative dominance (G159A). A defect in polyinosinic-polycytidylic acid-induced TLR3 responses can be detected in fibroblasts heterozygous for G159A but not for D50A TBK1. Nevertheless, viral replication and cell death rates caused by two TLR3-dependent viruses (HSV-1 and vesicular stomatitis virus) were high in fibroblasts from both patients, and particularly so in G159A TBK1 fibroblasts. These phenotypes were rescued equally well by IFN-α2b. Moreover, the IFN responses to the TLR3-independent agonists and viruses tested were maintained in both patients' peripheral blood mononuclear cells and fibroblasts. The narrow, partial cellular phenotype thus accounts for the clinical phenotype of these patients being limited to HSE. These data identify AD partial TBK1 deficiency as a new genetic etiology of childhood HSE, indicating that TBK1 is essential for the TLR3- and IFN-dependent control of HSV-1 in the CNS.


Assuntos
Encefalite por Herpes Simples/genética , Encefalite por Herpes Simples/imunologia , Mutação , Proteínas Serina-Treonina Quinases/genética , Receptor 3 Toll-Like/imunologia , Animais , Morte Celular/imunologia , Células Cultivadas , Criança , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Fibroblastos/virologia , Genes Dominantes , Herpesvirus Humano 1/patogenicidade , Humanos , Interferon beta/imunologia , Masculino , Camundongos , Poli I-C/farmacologia , Proteínas Serina-Treonina Quinases/imunologia , Vesiculovirus/patogenicidade
19.
J Clin Invest ; 121(12): 4889-902, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22105173

RESUMO

Herpes simplex encephalitis (HSE) is the most common sporadic viral encephalitis of childhood. Autosomal recessive (AR) UNC-93B and TLR3 deficiencies and autosomal dominant (AD) TLR3 and TRAF3 deficiencies underlie HSE in some children. We report here unrelated HSE children with AR or AD TRIF deficiency. The AR form of the disease was found to be due to a homozygous nonsense mutation that resulted in a complete absence of the TRIF protein. Both the TLR3- and the TRIF-dependent TLR4 signaling pathways were abolished. The AD form of disease was found to be due to a heterozygous missense mutation, resulting in a dysfunctional protein. In this form of the disease, the TLR3 signaling pathway was impaired, whereas the TRIF-dependent TLR4 pathway was unaffected. Both patients, however, showed reduced capacity to respond to stimulation of the DExD/H-box helicases pathway. To date, the TRIF-deficient patients with HSE described herein have suffered from no other infections. Moreover, as observed in patients with other genetic etiologies of HSE, clinical penetrance was found to be incomplete, as some HSV-1-infected TRIF-deficient relatives have not developed HSE. Our results provide what we believe to be the first description of human TRIF deficiency and a new genetic etiology for HSE. They suggest that the TRIF-dependent TLR4 and DExD/H-box helicase pathways are largely redundant in host defense. They further demonstrate the importance of TRIF for the TLR3-dependent production of antiviral IFNs in the CNS during primary infection with HSV-1 in childhood.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/deficiência , Encefalite por Herpes Simples/genética , Herpesvirus Humano 1 , Proteínas Adaptadoras de Transporte Vesicular/genética , Proteínas Adaptadoras de Transporte Vesicular/fisiologia , Sequência de Aminoácidos , Pré-Escolar , Códon sem Sentido , Consanguinidade , RNA Helicases DEAD-box/fisiologia , Feminino , Genes Dominantes , Genes Recessivos , Heterogeneidade Genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Lactente , Interferon-alfa/biossíntese , Interferon-alfa/genética , Masculino , Dados de Sequência Molecular , Mutação de Sentido Incorreto , Linhagem , Arábia Saudita , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transdução de Sinais/fisiologia , Receptor 3 Toll-Like/fisiologia , Receptor 4 Toll-Like/fisiologia
20.
J Exp Med ; 208(10): 2083-98, 2011 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-21911422

RESUMO

Autosomal dominant TLR3 deficiency has been identified as a genetic etiology of childhood herpes simplex virus 1 (HSV-1) encephalitis (HSE). This defect is partial, as it results in impaired, but not abolished induction of IFN-ß and -λ in fibroblasts in response to TLR3 stimulation. The apparently normal resistance of these patients to other infections, viral illnesses in particular, may thus result from residual TLR3 responses. We report here an autosomal recessive form of complete TLR3 deficiency in a young man who developed HSE in childhood but remained normally resistant to other infections. This patient is compound heterozygous for two loss-of-function TLR3 alleles, resulting in an absence of response to TLR3 activation by polyinosinic-polycytidylic acid (poly(I:C)) and related agonists in his fibroblasts. Moreover, upon infection of the patient's fibroblasts with HSV-1, the impairment of IFN-ß and -λ production resulted in high levels of viral replication and cell death. In contrast, the patient's peripheral blood mononuclear cells responded normally to poly(I:C) and to all viruses tested, including HSV-1. Consistently, various TLR3-deficient leukocytes from the patient, including CD14(+) and/or CD16(+) monocytes, plasmacytoid dendritic cells, and in vitro derived monocyte-derived macrophages, responded normally to both poly(I:C) and HSV-1, with the induction of antiviral IFN production. These findings identify a new genetic etiology for childhood HSE, indicating that TLR3-mediated immunity is essential for protective immunity to HSV-1 in the central nervous system (CNS) during primary infection in childhood, in at least some patients. They also indicate that human TLR3 is largely redundant for responses to double-stranded RNA and HSV-1 in various leukocytes, probably accounting for the redundancy of TLR3 for host defense against viruses, including HSV-1, outside the CNS.


Assuntos
Encefalite por Herpes Simples/imunologia , Imunidade/imunologia , Simplexvirus/imunologia , Receptor 3 Toll-Like/deficiência , Células Cultivadas , Análise Mutacional de DNA , Encefalite por Herpes Simples/genética , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/fisiologia , Estudo de Associação Genômica Ampla , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/imunologia , Masculino , Mutação , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/imunologia , Linhagem , Poli I-C/imunologia , Poli I-C/farmacologia , Simplexvirus/genética , Receptor 3 Toll-Like/genética , Adulto Jovem
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