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1.
Virulence ; 14(1): 2215602, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37221835

RESUMO

BACKGROUND: Mycobacterium abscessus subspecies massiliense (M. massiliense) is increasingly recognized as an emerging bacterial pathogen, particularly in cystic fibrosis (CF) patients and CF centres' respiratory outbreaks. We characterized genomic and phenotypic changes in 15 serial isolates from two CF patients (1S and 2B) with chronic pulmonary M. massiliense infection leading to death, as well as four isolates from a CF centre outbreak in which patient 2B was the index case. RESULTS: Comparative genomic analysis revealed the mutations affecting growth rate, metabolism, transport, lipids (loss of glycopeptidolipids), antibiotic susceptibility (macrolides and aminoglycosides resistance), and virulence factors. Mutations in 23S rRNA, mmpL4, porin locus and tetR genes occurred in isolates from both CF patients. Interestingly, we identified two different spontaneous mutation events at the mycobacterial porin locus: a fusion of two tandem porin paralogs in patient 1S and a partial deletion of the first porin paralog in patient 2B. These genomic changes correlated with reduced porin protein expression, diminished 14C-glucose uptake, slower bacterial growth rates, and enhanced TNF-α induction in mycobacteria-infected THP-1 human cells. Porin gene complementation of porin mutants partly restored 14C-glucose uptake, growth rate and TNF-α levels to those of intact porin strains. CONCLUSIONS: We hypothesize that specific mutations accumulated and maintained over time in M. massiliense, including mutations shared among transmissible strains, collectively lead to more virulent, host adapted lineages in CF patients and other susceptible hosts.


Assuntos
Fibrose Cística , Mycobacterium abscessus , Mycobacterium , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Fibrose Cística/microbiologia , Genômica , Glucose , Pulmão , Mutação , Mycobacterium/genética , Mycobacterium abscessus/genética , Fator de Necrose Tumoral alfa/genética , Porinas/genética , Porinas/metabolismo
2.
Open Forum Infect Dis ; 6(12): ofz484, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31807607

RESUMO

OBJECTIVE: Although disseminated nontuberculous mycobacterial infection is attributed to defects in the interleukin (IL)-12/interferon-γ circuit, the immunophenotype of idiopathic pulmonary nontuberculous mycobacterial (PNTM) disease is not well defined. METHOD: We phenotyped Th1, Th2, Th17, and Treg cytokines and colony-stimulating factor production from patients with idiopathic PNTM disease. Data were compared with healthy donors, cystic fibrosis (CF), and primary ciliary dyskinesia (PCD) patients with PNTM disease. Both supernatant cytokine production and intracellular cytokines expressed by various leukocyte subpopulations following mitogen and antigen stimulation were assayed by electrochemiluminescence-based multiplex immunoassay and flow cytometry, respectively. RESULTS: Regardless of antigen or mitogen stimulation, neither intracellular nor extracellular Th1, Th2, and Treg cytokine levels differed between patients and controls. Th17 cells and IL-17A levels were lower in idiopathic PNTM patients, whereas monocyte granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in response to NTM stimulation was higher compared with healthy donors. Besides, distinct cytokine responses following stimulation by Mycobacterium abscessus and Mycobacterium avium were observed consistently within each group. CONCLUSIONS: The IL-12/IFN-γ circuit appeared intact in patients with idiopathic PNTM disease. However, idiopathic PNTM patients had reduced Th17 response and higher mycobacteria-induced monocyte GM-CSF expression.

3.
J Allergy Clin Immunol ; 141(5): 1844-1853.e2, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28859974

RESUMO

BACKGROUND: Sumoylation is a posttranslational reversible modification of cellular proteins through the conjugation of small ubiquitin-related modifier (SUMO) and comprises an important regulator of protein function. OBJECTIVE: We sought to characterize the molecular mechanism of a novel mutation at the SUMO motif on signal transducer and activator of transcription 1 (STAT1). METHODS: STAT1 sequencing and functional characterization were performed in transfection experiments by using immunoblotting and immunoprecipitation in STAT1-deficient cell lines. Transcriptional response and target gene activation were also investigated in PBMCs. RESULTS: We identified a novel STAT1 mutation (c.2114A>T, p.E705V) within the SUMO motif (702IKTE705) in a patient with disseminated Rhodococcus species infection, Norwegian scabies, chronic mucocutaneous candidiasis, hypothyroidism, and esophageal squamous cell carcinoma. The mutation is located in the tail segment and is predicted to disrupt STAT1 sumoylation. Immunoprecipitation experiments performed in transfected cells confirmed absent STAT1 sumoylation for E705V, whereas it was present in wild-type (WT) STAT1 cells, as well as the loss-of-function mutants L706S and Y701C. Furthermore, stimulation with IFN-γ led to enhanced STAT1 phosphorylation, enhanced transcriptional activity, and target gene expression in the E705V-transfected compared with WT-transfected cells. Computer modeling of WT and mutant STAT1 molecules showed variations in the accessibility of the phosphorylation site Y701, which corresponded to the loss-of-function and gain-of-function variants. CONCLUSION: This is the first report of a mutation in the STAT1 sumoylation motif associated with clinical disease. These data reinforce sumoylation as a key posttranslational regulatory modification of STAT1 and identify a novel mechanism for gain-of-function STAT1 disease in human subjects.


Assuntos
Mutação com Ganho de Função/imunologia , Mutação/genética , Fator de Transcrição STAT1/genética , Ubiquitina/genética , Animais , Células COS , Candidíase Mucocutânea Crônica/genética , Linhagem Celular , Chlorocebus aethiops , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Expressão Gênica/genética , Humanos , Fosforilação/genética , Proteína SUMO-1/genética , Sumoilação/genética , Transcrição Gênica/genética , Ativação Transcricional/genética , Transfecção/métodos
4.
Am J Respir Cell Mol Biol ; 58(2): 241-252, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28915071

RESUMO

The incidence of pulmonary nontuberculous mycobacteria (NTM) disease is increasing, but host responses in respiratory epithelium infected with NTM are not fully understood. In this work, we aimed to identify infection-relevant gene expression signatures of NTM infection of the respiratory epithelium. We infected air-liquid interface (ALI) primary respiratory epithelial cell cultures with Mycobacterium avium subsp. avium (MAC) or Mycobacterium abscessus subsp. abscessus (MAB). We used cells from four different donors to obtain generalizable data. Differentiated respiratory epithelial cells at the ALI were infected with MAC or MAB at a multiplicity of infection of 100:1 or 1,000:1, and RNA sequencing was performed at Days 1 and 3 after infection. In response to infection, we found down-regulation of ciliary genes but upregulation of genes associated with cytokines/chemokines, such as IL-32, and cholesterol biosynthesis. Inflammatory response genes tended to be more upregulated by MAB than by MAC infection. Primary respiratory epithelial cell infection with NTM at the ALI identified ciliary function, cholesterol biosynthesis, and cytokine/chemokine production as major host responses to infection. Some of these pathways may be amenable to therapeutic manipulation.


Assuntos
Colesterol/biossíntese , Células Epiteliais/metabolismo , Infecções por Mycobacterium não Tuberculosas/imunologia , Micobactérias não Tuberculosas/imunologia , Mucosa Respiratória/metabolismo , Adulto , Idoso , Aderência Bacteriana/fisiologia , Movimento Celular/fisiologia , Células Cultivadas , Células Epiteliais/microbiologia , Feminino , Perfilação da Expressão Gênica , Humanos , Interleucina-17/biossíntese , Interleucina-17/imunologia , Interleucinas/biossíntese , Interleucinas/imunologia , Pulmão/imunologia , Pulmão/microbiologia , Pulmão/patologia , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/genética , Infecções por Mycobacterium não Tuberculosas/microbiologia , Mucosa Respiratória/citologia , Mucosa Respiratória/microbiologia
6.
Clin Infect Dis ; 62(8): 986-94, 2016 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-26743090

RESUMO

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a rare, severe, otherwise fatal viral infection of the white matter of the brain caused by the polyomavirus JC virus, which typically occurs only in immunocompromised patients. One patient with dominant gain-of-function (GOF) mutation in signal transducer and activator of transcription 1 (STAT1) with chronic mucocutaneous candidiasis and PML was reported previously. We aim to identify the molecular defect in 3 patients with PML and to review the literature on PML in primary immune defects (PIDs). METHODS: STAT1 was sequenced in 3 patients with PML. U3C cell lines were transfected with STAT1 and assays to search for STAT1 phosphorylation, transcriptional response, and target gene expression were performed. RESULTS: We identified 3 new unrelated cases of PML in patients with GOF STAT1 mutations, including the novel STAT1 mutation, L400Q. These STAT1 mutations caused delayed STAT1 dephosphorylation and enhanced interferon-gamma-driven responses. In our review of the literature regarding PML in primary immune deficiencies we found 26 cases, only 54% of which were molecularly characterized, the remainder being syndromically diagnosed only. CONCLUSIONS: The occurrence of PML in 4 cases of STAT1 GOF suggests that STAT1 plays a critical role in the control of JC virus in the central nervous system.


Assuntos
Síndromes de Imunodeficiência/genética , Leucoencefalopatia Multifocal Progressiva/genética , Mutação , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT1/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Linhagem Celular Tumoral , Feminino , Regulação da Expressão Gênica , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/diagnóstico por imagem , Interferon gama/farmacologia , Vírus JC/crescimento & desenvolvimento , Leucoencefalopatia Multifocal Progressiva/complicações , Leucoencefalopatia Multifocal Progressiva/diagnóstico por imagem , Leucoencefalopatia Multifocal Progressiva/imunologia , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA , Ativação Transcricional , Carga Viral , Adulto Jovem
7.
J Immunol ; 195(6): 2763-73, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26268658

RESUMO

Pulmonary tuberculosis (TB) is characterized by oxidative stress and lung tissue destruction by matrix metalloproteinases (MMPs). The interplay between these distinct pathological processes and the implications for TB diagnosis and disease staging are poorly understood. Heme oxygenase-1 (HO-1) levels were previously shown to distinguish active from latent TB, as well as successfully treated Mycobacterium tuberculosis infection. MMP-1 expression is also associated with active TB. In this study, we measured plasma levels of these two important biomarkers in distinct TB cohorts from India and Brazil. Patients with active TB expressed either very high levels of HO-1 and low levels of MMP-1 or the converse. Moreover, TB patients with either high HO-1 or MMP-1 levels displayed distinct clinical presentations, as well as plasma inflammatory marker profiles. In contrast, in an exploratory North American study, inversely correlated expression of HO-1 and MMP-1 was not observed in patients with other nontuberculous lung diseases. To assess possible regulatory interactions in the biosynthesis of these two enzymes at the cellular level, we studied the expression of HO-1 and MMP-1 in M. tuberculosis-infected human and murine macrophages. We found that infection of macrophages with live virulent M. tuberculosis is required for robust induction of high levels of HO-1 but not MMP-1. In addition, we observed that CO, a product of M. tuberculosis-induced HO-1 activity, inhibits MMP-1 expression by suppressing c-Jun/AP-1 activation. These findings reveal a mechanistic link between oxidative stress and tissue remodeling that may find applicability in the clinical staging of TB patients.


Assuntos
Heme Oxigenase-1/sangue , Metaloproteinase 1 da Matriz/sangue , Estresse Oxidativo/fisiologia , Tuberculose Pulmonar/patologia , Adulto , Idoso , Biomarcadores/sangue , Brasil , Feminino , Heme Oxigenase-1/metabolismo , Humanos , Índia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas de Ligação a TGF-beta Latente/sangue , Pulmão/microbiologia , Pulmão/patologia , Macrófagos/microbiologia , Macrófagos/patologia , Masculino , Metaloproteinase 1 da Matriz/biossíntese , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Fator de Transcrição AP-1/metabolismo , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/microbiologia , Estados Unidos , Adulto Jovem
8.
J Clin Microbiol ; 53(11): 3438-47, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26292297

RESUMO

The smooth-to-rough colony morphology shift in Mycobacterium abscessus has been implicated in loss of glycopeptidolipid (GPL), increased pathogenicity, and clinical decline in cystic fibrosis (CF) patients. However, the evolutionary phenotypic and genetic changes remain obscure. Serial isolates from nine non-CF patients with persistent M. abscessus infection were characterized by colony morphology, lipid profile via thin-layer chromatography and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), sequencing of eight genes in the GPL locus, and expression level of fadD23, a key gene involved in the biosynthesis of complex lipids. All 50 isolates were typed as M. abscessus subspecies abscessus and were clonally related within each patient. Rough isolates, all lacking GPL, predominated at later disease stages, some showing variation within rough morphology. While most (77%) rough isolates harbored detrimental mutations in mps1 and mps2, 13% displayed previously unreported mutations in mmpL4a and mmpS4, the latter yielding a putative GPL precursor. Two isolates showed no deleterious mutations in any of the eight genes sequenced. Mixed populations harboring different GPL locus mutations were detected in 5 patients, demonstrating clonal diversification, which was likely overlooked by conventional acid-fast bacillus (AFB) culture methods. Our work highlights applications of MALDI-TOF MS beyond identification, focusing on mycobacterial lipids relevant in virulence and adaptation. Later isolates displayed accumulation of triacylglycerol and reduced expression of fadD23, sometimes preceding rough colony onset. Our results indicate that clonal diversification and a shift in lipid metabolism, including the loss of GPL, occur during chronic lung infection with M. abscessus. GPL loss alone may not account for all traits associated with rough morphology.


Assuntos
Proteínas de Bactérias/genética , Ligases/genética , Metabolismo dos Lipídeos/genética , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/isolamento & purificação , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Bronquiectasia/microbiologia , Fibrose Cística/microbiologia , DNA Bacteriano/genética , Feminino , Dosagem de Genes/genética , Genoma Bacteriano/genética , Humanos , Lipídeos/genética , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Emerg Infect Dis ; 20(3): 364-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24565502

RESUMO

Three recently sequenced strains isolated from patients during an outbreak of Mycobacterium abscessus subsp. massiliense infections at a cystic fibrosis center in the United States were compared with 6 strains from an outbreak at a cystic fibrosis center in the United Kingdom and worldwide strains. Strains from the 2 cystic fibrosis outbreaks showed high-level relatedness with each other and major-level relatedness with strains that caused soft tissue infections during an epidemic in Brazil. We identified unique single-nucleotide polymorphisms in cystic fibrosis and soft tissue outbreak strains, separate single-nucleotide polymorphisms only in cystic fibrosis outbreak strains, and unique genomic traits for each subset of isolates. Our findings highlight the necessity of identifying M. abscessus to the subspecies level and screening all cystic fibrosis isolates for relatedness to these outbreak strains. We propose 2 diagnostic strategies that use partial sequencing of rpoB and secA1 genes and a multilocus sequence typing protocol.


Assuntos
Surtos de Doenças , Infecções por Mycobacterium/epidemiologia , Mycobacterium/isolamento & purificação , Brasil , Fibrose Cística/complicações , Genoma Bacteriano , Humanos , Tipagem de Sequências Multilocus , Mycobacterium/classificação , Mycobacterium/genética , Infecções por Mycobacterium/complicações , Infecções por Mycobacterium/diagnóstico , Infecções por Mycobacterium/microbiologia , Filogenia , Polimorfismo de Nucleotídeo Único , Reino Unido , Estados Unidos
10.
Ann Am Thorac Soc ; 11(1): 30-5, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24460437

RESUMO

RATIONALE: Treatment of pulmonary nontuberculous mycobacteria, especially Mycobacterium abscessus, requires prolonged, multidrug regimens with high toxicity and suboptimal efficacy. Options for refractory disease are limited. OBJECTIVES: We reviewed the efficacy and toxicity of inhaled amikacin in patients with treatment-refractory nontuberculous mycobacterial lung disease. METHODS: Records were queried to identify patients who had inhaled amikacin added to failing regimens. Lower airway microbiology, symptoms, and computed tomography scan changes were assessed together with reported toxicity. MEASUREMENTS AND MAIN RESULTS: The majority (80%) of the 20 patients who met entry criteria were women; all had bronchiectasis, two had cystic fibrosis and one had primary ciliary dyskinesia. At initiation of inhaled amikacin, 15 were culture positive for M. abscessus and 5 for Mycobacterium avium complex and had received a median (range) of 60 (6, 190) months of mycobacterial treatment. Patients were followed for a median of 19 (1, 50) months. Eight (40%) patients had at least one negative culture and 5 (25%) had persistently negative cultures. A decrease in smear quantity was noted in 9 of 20 (45%) and in mycobacterial culture growth for 10 of 19 (53%). Symptom scores improved in nine (45%), were unchanged in seven (35%), and worsened in four (20%). Improvement on computed tomography scans was noted in 6 (30%), unchanged in 3 (15%), and worsened in 11 (55%). Seven (35%) stopped amikacin due to: ototoxicity in two (10%), hemoptysis in two (10%), and nephrotoxicity, persistent dysphonia, and vertigo in one each. CONCLUSIONS: In some patients with treatment-refractory pulmonary nontuberculous mycobacterial disease, the addition of inhaled amikacin was associated with microbiologic and/or symptomatic improvement; however, toxicity was common. Prospective evaluation of inhaled amikacin for mycobacterial disease is warranted.


Assuntos
Amicacina/uso terapêutico , Antibacterianos/uso terapêutico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Administração por Inalação , Adulto , Idoso , Bronquiectasia/complicações , Fibrose Cística/complicações , Feminino , Humanos , Síndrome de Kartagener/complicações , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/complicações , Complexo Mycobacterium avium/isolamento & purificação , Infecção por Mycobacterium avium-intracellulare/complicações , Infecção por Mycobacterium avium-intracellulare/tratamento farmacológico , Micobactérias não Tuberculosas/isolamento & purificação , Estudos Retrospectivos , Escarro/microbiologia , Resultado do Tratamento , Tuberculose Pulmonar/complicações
11.
Genome Announc ; 1(5)2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-24136849

RESUMO

The Burkholderia cepacia complex (BCC) is a group of closely related bacteria that are responsible for respiratory infections in immunocompromised humans, most notably those with cystic fibrosis (CF). We report the genome sequences for Burkholderia cenocepacia ET12 lineage CF isolates K56-2 and BC7.

12.
PLoS One ; 8(6): e65102, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23750235

RESUMO

The first described, environmentally isolated, Bordetella petrii was shown to undergo massive genomic rearrangements in vitro. More recently, B. petrii was isolated from clinical samples associated with jaw, ear bone, cystic fibrosis and chronic pulmonary disease. However, the in vivo consequences of B. petrii genome plasticity and its pathogenicity remain obscure. B. petrii was identified from four sequential respiratory samples and a post-mortem spleen sample of a woman presenting with bronchiectasis and cavitary lung disease associated with nontuberculous mycobacterial infection. Strains were compared genetically, phenotypically and by antibody recognition from the patient and from inoculated mice. The successive B. petrii strains exhibited differences in growth, antibiotic susceptibility and recognition by the patient's antibodies. Antibodies from mice inoculated with these strains recapitulated the specificity and strain dependent response that was seen with the patient's serum. Finally, we characterize one strain that was poorly recognized by the patient's antibodies, due to a defect in the lipopolysaccharide O-antigen, and identify a mutation associated with this phenotype. We propose that B. petrii is remarkably adaptable in vivo, providing a possible connection between immune response and bacterial evasion and supporting infection persistence.


Assuntos
Adaptação Fisiológica , Bordetella/fisiologia , Imunidade Adaptativa , Animais , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Bordetella/genética , Bordetella/imunologia , Feminino , Humanos , Evasão da Resposta Imune , Imunização , Pneumopatias/sangue , Pneumopatias/imunologia , Pneumopatias/microbiologia , Camundongos , Pessoa de Meia-Idade , Mutação , Antígenos O/genética , Análise de Sequência
13.
J Allergy Clin Immunol ; 131(6): 1611-23, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23534974

RESUMO

BACKGROUND: Mutations in signal transducer and activator of transcription (STAT) 1 cause a broad spectrum of disease, ranging from severe viral and bacterial infections (amorphic alleles) to mild disseminated mycobacterial disease (hypomorphic alleles) to chronic mucocutaneous candidiasis (CMC; hypermorphic alleles). The hypermorphic mutations are also associated with arterial aneurysms, autoimmunity, and squamous cell cancers. OBJECTIVE: We sought to investigate the role of STAT1 gain-of-function mutations in phenotypes other than CMC. METHODS: We initially screened patients with CMC and autoimmunity for STAT1 mutations. We functionally characterized mutations in vitro and studied immune profiles and regulatory T (Treg) cells. After our initial case identifications, we explored 2 large cohorts of patients with wild-type forkhead box protein 3 and an immune dysregulation-polyendocrinopathy-enteropathy-X-linked (IPEX)-like phenotype for STAT1 mutations. RESULTS: We identified 5 children with polyendocrinopathy, enteropathy, and dermatitis reminiscent of IPEX syndrome; all but 1 had a variety of mucosal and disseminated fungal infections. All patients lacked forkhead box protein 3 mutations but had uniallelic STAT1 mutations (c.629 G>T, p.R210I; c.1073 T>G, p.L358W, c.796G>A; p.V266I; c.1154C>T, T385M [2 patients]). STAT1 phosphorylation in response to IFN-γ, IL-6, and IL-21 was increased and prolonged. CD4(+) IL-17-producing T-cell numbers were diminished. All patients had normal Treg cell percentages in the CD4(+) T-cell compartment, and their function was intact in the 2 patients tested. Patients with cells available for study had normal levels of IL-2-induced STAT5 phosphorylation. CONCLUSIONS: Gain-of-function mutations in STAT1 can cause an IPEX-like phenotype with normal frequency and function of Treg cells.


Assuntos
Fatores de Transcrição Forkhead/genética , Genes Dominantes , Doenças Genéticas Ligadas ao Cromossomo X/genética , Enteropatias/genética , Mutação , Poliendocrinopatias Autoimunes/genética , Fator de Transcrição STAT1/genética , Adolescente , Autoanticorpos/imunologia , Linhagem Celular Transformada , Criança , Pré-Escolar , DNA/metabolismo , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Doenças Genéticas Ligadas ao Cromossomo X/imunologia , Humanos , Imunofenotipagem , Interferon-alfa/imunologia , Interferon gama/farmacologia , Interleucina-17/imunologia , Interleucinas/imunologia , Enteropatias/diagnóstico , Enteropatias/imunologia , Subpopulações de Linfócitos/imunologia , Subpopulações de Linfócitos/metabolismo , Masculino , Fenótipo , Fosforilação/efeitos dos fármacos , Poliendocrinopatias Autoimunes/diagnóstico , Poliendocrinopatias Autoimunes/imunologia , Fator de Transcrição STAT1/metabolismo , Síndrome , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo , Ativação Transcricional , Interleucina 22
14.
J Bacteriol ; 194(22): 6356-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23105085

RESUMO

Burkholderia multivorans is a Gram-negative bacterium and a member of the Burkholderia cepacia complex, which is frequently associated with respiratory infections in people with cystic fibrosis (CF) and chronic granulomatous disease (CGD). We are reporting the genome sequences of 4 B. multivorans strains, 2 from CF patients and 2 from CGD patients.


Assuntos
Burkholderia/classificação , Burkholderia/genética , Fibrose Cística/microbiologia , Genoma Bacteriano , Doença Granulomatosa Crônica/microbiologia , Humanos , Dados de Sequência Molecular
15.
J Clin Immunol ; 32(4): 681-689, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22437822

RESUMO

STAT1 is a key component of Interferon (IFN)-γ and IFN-α signaling and mediates protection against mycobacteria, fungal, viral infections, and cancer. Dominant negative inhibitory as well as gain of function heterozygous STAT1 mutations demonstrate that IFN-γ driven cellular responses need to be tightly regulated to control infections. We describe an autosomal dominant mutation in the SH2 domain of STAT1 that disrupts protein phosphorylation, c.1961T>A (M654K). The mutant allele does not permit STAT1 phosphorylation, and impairs STAT1 phosphorylation of the wild type allele. Protein dimerization is preserved but DNA binding activity, IFN-γ driven GAS-luciferase activity, and expression of IFN-γ target genes are reduced. IFN-α driven ISRE response, but not IFN-α driven GAS response, are preserved when cells are co-transfected with wild type and the mutant STAT1 constructs. M654K exerts a dominant negative effect on IFN-γ related immunity and is recessive for IFN-α induced immune function.


Assuntos
Infecções por Mycobacterium não Tuberculosas/genética , Complexo Mycobacterium avium/patogenicidade , Fator de Transcrição STAT1/genética , Linfócitos B , Linhagem Celular , Pré-Escolar , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Interferon-alfa/genética , Interferon-alfa/metabolismo , Interferon gama/genética , Interferon gama/metabolismo , Masculino , Mutação , Infecções por Mycobacterium não Tuberculosas/microbiologia , Fosforilação , Multimerização Proteica , Fator de Transcrição STAT1/metabolismo , Transdução de Sinais/genética
16.
J Infect Dis ; 204(8): 1256-63, 2011 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-21917899

RESUMO

Leprosy is an infectious disease caused by Mycobacterium leprae. Tumor necrosis factor (TNF) plays a key role in the host response. Some association studies have implicated the single nucleotide polymorphism TNF -308G>A in leprosy susceptibility, but these results are still controversial. We first conducted 4 association studies (2639 individuals) that showed a protective effect of the -308A allele (odds ratio [OR] = 0.77; P = .005). Next, results of a meta-analysis reinforced this association after inclusion of our new data (OR = 0.74; P = .04). Furthermore, a subgroup analysis including only Brazilian studies suggested that the association is specific to this population (OR = 0.63; P = .005). Finally, functional analyses using whole blood cultures showed that patients carrying the -308A allele produced higher TNF levels after lipopolysaccharide (LPS) (6 hours) and M. leprae (3 hours) stimulation. These results reinforce the association between TNF and leprosy and suggest the -308A allele as a marker of disease resistance, especially among Brazilians.


Assuntos
Hanseníase/genética , Mycobacterium leprae/isolamento & purificação , Fator de Necrose Tumoral alfa/genética , Adulto , Brasil/epidemiologia , Estudos de Casos e Controles , DNA/química , DNA/genética , Feminino , Variação Genética , Genótipo , Humanos , Hanseníase/epidemiologia , Hanseníase/microbiologia , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Adulto Jovem
17.
Blood ; 118(10): 2653-5, 2011 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-21670465

RESUMO

The syndrome of monocytopenia, B-cell and NK-cell lymphopenia, and mycobacterial, fungal, and viral infections is associated with myelodysplasia, cytogenetic abnormalities, pulmonary alveolar proteinosis, and myeloid leukemias. Both autosomal dominant and sporadic cases occur. We identified 12 distinct mutations in GATA2 affecting 20 patients and relatives with this syndrome, including recurrent missense mutations affecting the zinc finger-2 domain (R398W and T354M), suggesting dominant interference of gene function. Four discrete insertion/deletion mutations leading to frame shifts and premature termination implicate haploinsufficiency as a possible mechanism of action as well. These mutations were found in hematopoietic and somatic tissues, and several were identified in families, indicating germline transmission. Thus, GATA2 joins RUNX1 and CEBPA not only as a familial leukemia gene but also as a cause of a complex congenital immunodeficiency that evolves over decades and combines predisposition to infection and myeloid malignancy.


Assuntos
Fator de Transcrição GATA2/genética , Predisposição Genética para Doença , Monócitos/patologia , Mutação/genética , Infecções por Mycobacterium/etiologia , Infecções por Mycobacterium/patologia , Mycobacterium/patogenicidade , Genes Dominantes , Humanos , Síndrome
18.
Blood ; 116(23): 4848-58, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-20716769

RESUMO

Patients with thymic malignancy have high rates of autoimmunity leading to a variety of autoimmune diseases, most commonly myasthenia gravis caused by anti-acetylcholine receptor autoantibodies. High rates of autoantibodies to cytokines have also been described, although prevalence, spectrum, and functionality of these anti-cytokine autoantibodies are poorly defined. To better understand the presence and function of anti-cytokine autoantibodies, we created a luciferase immunoprecipitation system panel to search for autoantibodies against 39 different cytokines and examined plasma from controls (n = 30) and patients with thymic neoplasia (n = 17). In this screen, our patients showed statistically elevated, but highly heterogeneous immunoreactivity against 16 of the 39 cytokines. Some patients showed autoantibodies to multiple cytokines. Functional testing proved that autoantibodies directed against interferon-α, interferon-ß, interleukin-1α (IL-1α), IL-12p35, IL-12p40, and IL-17A had biologic blocking activity in vitro. All patients with opportunistic infection showed multiple anti-cytokine autoantibodies (range 3-11), suggesting that anti-cytokine autoantibodies may be important in the pathogenesis of opportunistic infections in patients with thymic malignancy. This study was registered at http://clinicaltrials.gov as NCT00001355.


Assuntos
Autoanticorpos/sangue , Citocinas/imunologia , Infecções Oportunistas/imunologia , Neoplasias do Timo/complicações , Neoplasias do Timo/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Feminino , Humanos , Imunoensaio , Immunoblotting , Imunoprecipitação , Masculino , Pessoa de Meia-Idade , Infecções Oportunistas/sangue , Infecções Oportunistas/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias do Timo/sangue , Adulto Jovem
19.
Infect Immun ; 78(3): 1012-21, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20008541

RESUMO

Gelatinases A and B (matrix metalloproteinase 2 [MMP-2] and MMP-9, respectively) can induce basal membrane breakdown and leukocyte migration, but their role in leprosy skin inflammation remains unclear. In this study, we analyzed clinical specimens from leprosy patients taken from stable, untreated skin lesions and during reactional episodes (reversal reaction [RR] and erythema nodosum leprosum [ENL]). The participation of MMPs in disease was suggested by (i) increased MMP mRNA expression levels in skin biopsy specimens correlating with the expression of gamma interferon (IFN-gamma) and tumor necrosis factor alpha (TNF-alpha), (ii) the detection of the MMP protein and enzymatic activity within the inflammatory infiltrate, (iii) increased MMP levels in patient sera, and (iv) the in vitro induction of MMP-9 by Mycobacterium leprae and/or TNF-alpha. It was observed that IFN-gamma, TNF-alpha, MMP-2, and MMP-9 mRNA levels were higher in tuberculoid than lepromatous lesions. In contrast, interleukin-10 and tissue inhibitor of MMP (TIMP-1) message were not differentially modulated. These data correlated with the detection of the MMP protein evidenced by immunohistochemistry and confocal microscopy. When RR and ENL lesions were analyzed, an increase in TNF-alpha, MMP-2, and MMP-9, but not TIMP-1, mRNA levels was observed together with stronger MMP activity (zymography/in situ zymography). Moreover, following in vitro stimulation of peripheral blood cells, M. leprae induced the expression of MMP-9 (mRNA and protein) in cultured cells. Overall, the present data demonstrate an enhanced MMP/TIMP-1 ratio in the inflammatory states of leprosy and point to potential mechanisms for tissue damage. These results pave the way toward the application of new therapeutic interventions for leprosy reactions.


Assuntos
Hanseníase/imunologia , Leucócitos/imunologia , Metaloproteinases da Matriz/imunologia , Mycobacterium leprae/imunologia , Pele/imunologia , Pele/microbiologia , Adulto , Movimento Celular , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Inflamação , Mediadores da Inflamação/análise , Masculino , Microscopia Confocal , Pessoa de Meia-Idade , Pele/química , Pele/patologia , Adulto Jovem
20.
Blood ; 115(8): 1519-29, 2010 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-20040766

RESUMO

We identified 18 patients with the distinct clinical phenotype of susceptibility to disseminated nontuberculous mycobacterial infections, viral infections, especially with human papillomaviruses, and fungal infections, primarily histoplasmosis, and molds. This syndrome typically had its onset in adulthood (age range, 7-60 years; mean, 31.1 years; median, 32 years) and was characterized by profound circulating monocytopenia (mean, 13.3 cells/microL; median, 14.5 cells/microL), B lymphocytopenia (mean, 9.4 cells/microL; median, 4 cells/microL), and NK lymphocytopenia (mean, 16 cells/microL; median, 5.5 cells/microL). T lymphocytes were variably affected. Despite these peripheral cytopenias, all patients had macrophages and plasma cells at sites of inflammation and normal immunoglobulin levels. Ten of these patients developed 1 or more of the following malignancies: 9 myelodysplasia/leukemia, 1 vulvar carcinoma and metastatic melanoma, 1 cervical carcinoma, 1 Bowen disease of the vulva, and 1 multiple Epstein-Barr virus(+) leiomyosarcoma. Five patients developed pulmonary alveolar proteinosis without mutations in the granulocyte-macrophage colony-stimulating factor receptor or anti-granulocyte-macrophage colony-stimulating factor autoantibodies. Among these 18 patients, 5 families had 2 generations affected, suggesting autosomal dominant transmission as well as sporadic cases. This novel clinical syndrome links susceptibility to mycobacterial, viral, and fungal infections with malignancy and can be transmitted in an autosomal dominant pattern.


Assuntos
Doenças Genéticas Inatas/genética , Predisposição Genética para Doença/genética , Leucopenia/genética , Infecções por Mycobacterium/genética , Micoses/genética , Síndromes Mielodisplásicas/genética , Infecções por Papillomavirus/genética , Linhagem , Adolescente , Adulto , Criança , Feminino , Fungos , Doenças Genéticas Inatas/sangue , Doenças Genéticas Inatas/complicações , Humanos , Contagem de Leucócitos , Leucopenia/sangue , Leucopenia/complicações , Masculino , Pessoa de Meia-Idade , Mycobacterium , Infecções por Mycobacterium/sangue , Infecções por Mycobacterium/etiologia , Micoses/sangue , Micoses/etiologia , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/etiologia , Neoplasias/sangue , Neoplasias/etiologia , Neoplasias/genética , Papillomaviridae , Infecções por Papillomavirus/sangue , Infecções por Papillomavirus/etiologia
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