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1.
Curr Opin Infect Dis ; 32(4): 330-336, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31116133

RESUMO

PURPOSE OF REVIEW: The current review gives a concise and updated overview of the relative new field of anticytokine autoantibodies (ACAA) and associated infections with a focus on recent findings regarding clinical manifestions, diagnostic and treatments. RECENT FINDINGS: Several recent case reports of unusual presentations of patients with neutralizing autoantibodies to IFN-γ and granulocyt macrophage colony-stimulating factor and expand the spectrum of clinical manifestations and suggest that anticytokine-mediated acquired immunodeficiency causing susceptibility to infection may be underdiagnosed. There is an expanding geographical distribution of antigranulocyt macrophage colony-stimulating factor associated Cryptococcus gattii infection. The spectrum of identified infections in patients with neutralizing antibodies to IFN-γ has a strong endemic component. Rituximab or cyclophophamide in addition to antimycobacterials could be a treatment options in refractory cases. NF-κB2 deficiency may be associated with a complex pattern of high titre neutralizing ACAA similar to autoimmune polyglandular syndrome type I and Thymoma. New technique for the detection of anticytokine antibodies are presented. Quantiferon testing, which is widely available for TB-diagnostic, may be repurposed to detect anti-IFN-γ autoantibodies. We propose that this test could be as well used to show if they are neutralizing. SUMMARY: ACAA are an emerging cause of acquired immunodeficiency which is likely underdiagnosed. Recent case reports document expanding spectra of clinical manifestations. NF-κB2 deficiency may be associated with a complex anti cytokine autoantibody pattern.

2.
J Exp Med ; 216(6): 1311-1327, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31040185

RESUMO

Interleukin-2, which conveys essential signals for immunity, operates through a heterotrimeric receptor. Here we identify human interleukin-2 receptor (IL-2R) ß chain (IL2RB) gene defects as a cause of life-threatening immune dysregulation. We report three homozygous mutations in the IL2RB gene of eight individuals from four consanguineous families that cause disease by distinct mechanisms. Nearly all patients presented with autoantibodies, hypergammaglobulinemia, bowel inflammation, dermatological abnormalities, lymphadenopathy, and cytomegalovirus disease. Patient T lymphocytes lacked surface expression of IL-2Rß and were unable to respond to IL-2 stimulation. By contrast, natural killer cells retained partial IL-2Rß expression and function. IL-2Rß loss of function was recapitulated in a recombinant system in which IL2RB mutations caused reduced surface expression and IL-2 binding. Stem cell transplant ameliorated clinical symptoms in one patient; forced expression of wild-type IL-2Rß also increased the IL-2 responsiveness of patient T lymphocytes in vitro. Insights from these patients can inform the development of IL-2-based therapeutics for immunological diseases and cancer.

3.
Science ; 361(6404): 810-813, 2018 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-30026316

RESUMO

RIPK1 (receptor-interacting serine/threonine kinase 1) is a master regulator of signaling pathways leading to inflammation and cell death and is of medical interest as a drug target. We report four patients from three unrelated families with complete RIPK1 deficiency caused by rare homozygous mutations. The patients suffered from recurrent infections, early-onset inflammatory bowel disease, and progressive polyarthritis. They had immunodeficiency with lymphopenia and altered production of various cytokines revealed by whole-blood assays. In vitro, RIPK1-deficient cells showed impaired mitogen-activated protein kinase activation and cytokine secretion and were prone to necroptosis. Hematopoietic stem cell transplantation reversed cytokine production defects and resolved clinical symptoms in one patient. Thus, RIPK1 plays a critical role in the human immune system.


Assuntos
Artrite/genética , Doenças Inflamatórias Intestinais/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Imunodeficiência Combinada Severa/genética , Alelos , Artrite/imunologia , Citocinas/metabolismo , Feminino , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Doenças Inflamatórias Intestinais/imunologia , Linfopenia/genética , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Linhagem , Imunodeficiência Combinada Severa/imunologia
7.
J Allergy Clin Immunol ; 141(6): 2234-2248, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29128673

RESUMO

BACKGROUND: The homozygous K108E mutation of interferon regulatory factor 8 (IRF8) is reported to cause dendritic cell (DC) and monocyte deficiency. However, more widespread immune dysfunction is predicted from the multiple roles ascribed to IRF8 in immune cell development and function. OBJECTIVE: We sought to describe the effect on hematopoiesis and immunity of the compound heterozygous R83C/R291Q mutation of IRF8, which is present in a patient with recurrent viral infection, granuloproliferation, and intracerebral calcification. METHODS: Variant IRF8 alleles were identified by means of exome sequencing, and their function was tested by using reporter assays. The cellular phenotype was studied in detail by using flow cytometry, functional immunologic assay transcriptional profiling, and antigen receptor profiling. RESULTS: Both mutations affected conserved residues, and R291Q is orthologous to R294, which is mutated in the BXH2 IRF8-deficient mouse. R83C showed reduced nuclear translocation, and neither mutant was able to regulate the Ets/IRF composite element or interferon-stimulated response element, whereas R291Q retained BATF/JUN interactions. DC deficiency and monocytopenia were observed in blood, dermis, and lung lavage fluid. Granulocytes were consistently increased, dysplastic, and hypofunctional. Natural killer cell development and maturation were arrested. TH1, TH17, and CD8+ memory T-cell differentiation was significantly reduced, and T cells did not express CXCR3. B-cell development was impaired, with fewer memory cells, reduced class-switching, and lower frequency and complexity of somatic hypermutation. Cell-specific gene expression was widely disturbed in interferon- and IRF8-regulated transcripts. CONCLUSIONS: This analysis defines the clinical features of human biallelic IRF8 deficiency, revealing a complex immunodeficiency syndrome caused by DC and monocyte deficiency combined with widespread immune dysregulation.

8.
Front Immunol ; 9: 2863, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30619256

RESUMO

Background: The auto-inflammation and phospholipase Cγ2 (PLCγ2)-associated antibody deficiency and immune dysregulation (APLAID) syndrome is a rare primary immunodeficiency caused by a gain-of-function mutation S707Y in the PLCG2 gene previously described in two patients from one family. The APLAID patients presented with early-onset blistering skin lesions, posterior uveitis, inflammatory bowel disease (IBD) and recurrent sinopulmonary infections caused by a humoral defect, but lacked circulating autoantibodies and had no cold-induced urticaria, contrary to the patients with the related PLAID syndrome. Case: We describe a new APLAID patient who presented with vesiculopustular rash in the 1st weeks of life, followed by IBD, posterior uveitis, recurrent chest infections, interstitial pneumonitis, and also had sensorineural deafness and cutis laxa. Her disease has been refractory to most treatments, including IL1 blockers and a trial with ruxolitinib has been attempted. Results: In this patient, we found a unique de novo heterozygous missense L848P mutation in the PLCG2 gene, predicted to affect the PLCγ2 structure. Similarly to S707Y, the L848P mutation led to the increased basal and EGF-stimulated PLCγ2 activity in vitro. Whole blood assays showed reduced production of IFN-γ and IL-17 in response to polyclonal T-cell stimulation and reduced production of IL-10 and IL-1ß after LPS stimulation. Reduced IL-1ß levels and the lack of clinical response to treatment with IL-1 blockers argue against NLRP3 inflammasome hyperactivation being the main mechanism mediating the APLAID pathogenesis. Conclusion: Our findings indicate that L848P is novel a gain-of-function mutation that leads to PLCγ2 activation and suggest cutis laxa as a possible clinical manifestations of the APLAID syndrome.


Assuntos
Cútis Laxa/genética , Doenças Hereditárias Autoinflamatórias/genética , Síndromes de Imunodeficiência/genética , Mutação de Sentido Incorreto , Fosfolipase C gama/genética , Sequência de Aminoácidos , Sequência de Bases , Cútis Laxa/complicações , Cútis Laxa/enzimologia , Análise Mutacional de DNA , Feminino , Doenças Hereditárias Autoinflamatórias/complicações , Doenças Hereditárias Autoinflamatórias/enzimologia , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/enzimologia , Recém-Nascido , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/genética , Masculino , Linhagem , Fosfolipase C gama/química , Fosfolipase C gama/metabolismo , Homologia de Sequência de Aminoácidos
9.
RMD Open ; 3(2): e000550, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29177082

RESUMO

At the population level, rheumatoid arthritis (RA) is generally viewed as autoimmune in nature with a small subgroup of cases having a palindromic form or systemic autoinflammatory disorder (SAID) phenotype. Herein, we describe resistant cases of classical autoantibody associated RA that had clinical, genetic and therapeutic responses indicative of coexistent autoinflammatory disease. Five patients with clinically overlapping features between RA and SAID including polysynovitis and autoantibody/shared epitope positivity, and who had abrupt severe self-limiting attacks including fevers and serositis, are described. Mutations or single nucleotide polymorphisms in recognised autoinflammatory pathways were evident. Generally, these cases responded poorly to conventional Disease-modifying anti-rheumatic drugs (DMARD) treatment with some excellent responses to colchicine or interleukin 1 pathway blockade. A subgroup of RA cases have a mixed autoimmune-autoinflammatory phenotype and genotype with therapeutic implications.

10.
Front Immunol ; 8: 1485, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29163546

RESUMO

G6PC3 deficiency typically causes severe congenital neutropenia, associated with susceptibility to infections, cardiac and urogenital abnormalities. However, here we describe two boys of Pakistani origin who were found to have G6PC3 deficiency due to c.130 C>T mutation, but who have clinical phenotypes that are typical for a systemic autoinflammatory syndrome. The index case presented with combination of unexplained fevers, severe mucosal ulcers, abdominal symptoms, and inflammatory arthritis. He eventually fully responded to anti-TNF therapy. In this study, we show that compared with healthy controls, neutrophils and monocytes from patients have reduced glycolytic reserve. Considering that healthy myeloid cells have been shown to switch their metabolic pathways to glycolysis in response to inflammatory cues, we studied what impact this might have on production of the inflammatory cytokines. We have demonstrated that patients' monocytes, in response to lipopolysaccharide, show significantly increased production of IL-1ß and IL-18, which is NLRP3 inflammasome dependent. Furthermore, additional whole blood assays have also shown an enhanced production of IL-6 and TNF from the patients' cells. These cases provide further proof that autoinflammatory complications are also seen within the spectrum of primary immune deficiencies, and resulting from a wider dysregulation of the immune responses.

11.
Blood ; 130(12): 1456-1467, 2017 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-28679735

RESUMO

X-linked recessive ectodermal dysplasia with immunodeficiency is a rare primary immunodeficiency caused by hypomorphic mutations of the IKBKG gene encoding the nuclear factor κB essential modulator (NEMO) protein. This condition displays enormous allelic, immunological, and clinical heterogeneity, and therapeutic decisions are difficult because NEMO operates in both hematopoietic and nonhematopoietic cells. Hematopoietic stem cell transplantation (HSCT) is potentially life-saving, but the small number of case reports available suggests it has been reserved for only the most severe cases. Here, we report the health status before HSCT, transplantation outcome, and clinical follow-up for a series of 29 patients from unrelated kindreds from 11 countries. Between them, these patients carry 23 different hypomorphic IKBKG mutations. HSCT was performed from HLA-identical related donors (n = 7), HLA-matched unrelated donors (n = 12), HLA-mismatched unrelated donors (n = 8), and HLA-haploidentical related donors (n = 2). Engraftment was documented in 24 patients, and graft-versus-host disease in 13 patients. Up to 7 patients died 0.2 to 12 months after HSCT. The global survival rate after HSCT among NEMO-deficient children was 74% at a median follow-up after HSCT of 57 months (range, 4-108 months). Preexisting mycobacterial infection and colitis were associated with poor HSCT outcome. The underlying mutation does not appear to have any influence, as patients with the same mutation had different outcomes. Transplantation did not appear to cure colitis, possibly as a result of cell-intrinsic disorders of the epithelial barrier. Overall, HSCT can cure most clinical features of patients with a variety of IKBKG mutations.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Quinase I-kappa B/genética , Mutação/genética , Pré-Escolar , Estudos de Coortes , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Heterozigoto , Humanos , Lactente , Recém-Nascido , Inflamação/patologia , Doenças Inflamatórias Intestinais/etiologia , NF-kappa B/metabolismo , Fenótipo , Transdução de Sinais/genética , Análise de Sobrevida , Doadores de Tecidos , Condicionamento Pré-Transplante , Resultado do Tratamento
13.
J Allergy Clin Immunol ; 139(2): 597-606.e4, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27555459

RESUMO

BACKGROUND: Activated phosphoinositide 3-kinase δ syndrome (APDS) is a recently described combined immunodeficiency resulting from gain-of-function mutations in PIK3CD, the gene encoding the catalytic subunit of phosphoinositide 3-kinase δ (PI3Kδ). OBJECTIVE: We sought to review the clinical, immunologic, histopathologic, and radiologic features of APDS in a large genetically defined international cohort. METHODS: We applied a clinical questionnaire and performed review of medical notes, radiology, histopathology, and laboratory investigations of 53 patients with APDS. RESULTS: Recurrent sinopulmonary infections (98%) and nonneoplastic lymphoproliferation (75%) were common, often from childhood. Other significant complications included herpesvirus infections (49%), autoinflammatory disease (34%), and lymphoma (13%). Unexpectedly, neurodevelopmental delay occurred in 19% of the cohort, suggesting a role for PI3Kδ in the central nervous system; consistent with this, PI3Kδ is broadly expressed in the developing murine central nervous system. Thoracic imaging revealed high rates of mosaic attenuation (90%) and bronchiectasis (60%). Increased IgM levels (78%), IgG deficiency (43%), and CD4 lymphopenia (84%) were significant immunologic features. No immunologic marker reliably predicted clinical severity, which ranged from asymptomatic to death in early childhood. The majority of patients received immunoglobulin replacement and antibiotic prophylaxis, and 5 patients underwent hematopoietic stem cell transplantation. Five patients died from complications of APDS. CONCLUSION: APDS is a combined immunodeficiency with multiple clinical manifestations, many with incomplete penetrance and others with variable expressivity. The severity of complications in some patients supports consideration of hematopoietic stem cell transplantation for severe childhood disease. Clinical trials of selective PI3Kδ inhibitors offer new prospects for APDS treatment.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Síndromes de Imunodeficiência/genética , Transtornos Linfoproliferativos/genética , Mutação/genética , Infecções Respiratórias/genética , Adolescente , Adulto , Animais , Antibioticoprofilaxia , Criança , Pré-Escolar , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Estudos de Coortes , Inibidores Enzimáticos/uso terapêutico , Feminino , Transplante de Células-Tronco Hematopoéticas , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/mortalidade , Infecções por Herpesviridae/terapia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/mortalidade , Síndromes de Imunodeficiência/terapia , Lactente , Cooperação Internacional , Transtornos Linfoproliferativos/mortalidade , Transtornos Linfoproliferativos/terapia , Masculino , Camundongos , Pessoa de Meia-Idade , Recidiva , Infecções Respiratórias/mortalidade , Infecções Respiratórias/terapia , Inquéritos e Questionários , Análise de Sobrevida , Adulto Jovem
14.
Case Reports Immunol ; 2016: 9165641, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27974980

RESUMO

Nontuberculous mycobacteria (NTMs) are weakly virulent intracellular pathogens that are common in food and water supplies. The persistent culture of these organisms in the setting of clinical infection warrants investigation of immune function. In cases of isolated pulmonary NTM (PNTM) disease, underlying immune defects have not been clearly identified. We present two patients with isolated PNTM infection who demonstrated differentially impaired IFN-γ production across a range of stimuli. These cases show that cellular IFN-γ responses may be defective in a proportion of patient suffering PNTM disease and that when assessing responses, the stimulant used in the testing is important to delineate defective cell populations. Impaired IFN-γ responses to IL-12 + BCG seem to be a poor prognostic indicator in PNTM disease and in these cases were not improved by adjuvant IFN-γ.

15.
Nat Commun ; 7: 13992, 2016 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-28008925

RESUMO

Mutations in genes encoding components of the immune system cause primary immunodeficiencies. Here, we study a patient with recurrent atypical mycobacterial infection and early-onset metastatic bladder carcinoma. Exome sequencing identified two homozygous missense germline mutations, P733L and P832S, in the JAK1 protein that mediates signalling from multiple cytokine receptors. Cells from this patient exhibit reduced JAK1 and STAT phosphorylation following cytokine stimulations, reduced induction of expression of interferon-regulated genes and dysregulated cytokine production; which are indicative of signalling defects in multiple immune response pathways including Interferon-γ production. Reconstitution experiments in the JAK1-deficient cells demonstrate that the impaired JAK1 function is mainly attributable to the effect of the P733L mutation. Further analyses of the mutant protein reveal a phosphorylation-independent role of JAK1 in signal transduction. These findings clarify JAK1 signalling mechanisms and demonstrate a critical function of JAK1 in protection against mycobacterial infection and possibly the immunological surveillance of cancer.


Assuntos
Alelos , Janus Quinase 1/genética , Mutação/genética , Infecções por Mycobacterium/enzimologia , Infecções por Mycobacterium/genética , Sequência de Aminoácidos , Sequência de Bases , Células Sanguíneas/metabolismo , Criança , Pré-Escolar , Citocinas/sangue , Suscetibilidade a Doenças , Feminino , Fibroblastos/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interferon-alfa/farmacologia , Interferon gama/farmacologia , Janus Quinase 1/química , Masculino , Linhagem , Fosforilação/efeitos dos fármacos , Domínios Proteicos , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais/genética , TYK2 Quinase/metabolismo , Adulto Jovem
16.
Curr Opin Allergy Clin Immunol ; 16(6): 523-529, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27755185

RESUMO

PURPOSE OF REVIEW: Concise overview of the field of anticytokine autoantibodies with a focus on recent developments. RECENT FINDINGS: Advances in particular in the analysis of autoantibodies to IFNγ, granulocyte-macrophage colony-stimulating factor (GM-CSF) and type I IFN are presented. The target epitope for anti-IFNγ autoantibodies has been found to have high homology to a protein from Aspergillus suggesting molecular mimicry as a mechanism of breaking self-tolerance. A treatment strategy using a recombinant, epitope-depleted version of IFNγ is suggested. Autoantibodies to GM-CSF are associated with disseminated Crytococcus and Nocardia infections thus expanding the spectrum of associated diseases beyond pulmonary alveolar proteinosis. Detailed analysis of anti-GM-CSF autoantibody clones derived from pulmonary alveolar proteinosis patients show evidence of high somatic mutation suggesting T cell-dependent affinity maturation; full GM-CSF neutralization is achieved by synergistic binding of antibodies targeting various distinct noncross-reactive epitopes and leading to antigen sequestration and Fc-mediated clearance. Single mAbs in contrast may lead to higher GM-CSF bioavailability. Anti type I IFN-specific autoantibodies derived from autoimmune polyglandular syndrome type I patients are of extreme high affinity and negatively correlate with the incidence of type I diabetes and may be thus considered to be protective. Hypomorphic severe combined immune deficiency may be associated with complex anticytokine patterns and the emergence of anti type I IFN autoantibodies correlates with severe viral infection histories. SUMMARY: Anticytokine autoantibodies may cause susceptibility to infections. In autoimmune/autoinflammatory conditions, anticytokine autoantibodies may be protective or promote disease.


Assuntos
Autoanticorpos/metabolismo , Infecção/imunologia , Inflamação/imunologia , Proteinose Alveolar Pulmonar/imunologia , Tolerância a Antígenos Próprios , Animais , Autoanticorpos/imunologia , Autoimunidade , Reações Cruzadas , Epitopos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Humanos , Interferons/imunologia
17.
Allergy Rhinol (Providence) ; 7(2): 102-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27658186

RESUMO

BACKGROUND: Chronic granulomatous invasive fungal rhinosinusitis (CGIFRS) is a rare disease. The underlying immune responses that drive the development of CGIFRS, as opposed to successful pathogen clearance and controlled inflammation, are not currently known. OBJECTIVE: To characterize the immune responses associated with CGIFRS. METHODS: In addition to a battery of basic investigations, more in-depth immunologic testing involves ex vivo whole-blood stimulation with the polyclonal T-cell mitogen phytohemagglutinin and fungal antigens with interleukin (IL) 12, was undertaken to investigate cell-mediated immune responses associated with CGIFRS. RESULTS: Ex vivo whole-blood stimulation with the polyclonal T-cell mitogen phytohemagglutinin and fungal antigens with IL-12 identified reduced interferon gamma and increased IL-17A levels within the supernatant, which indicated increased in vivo T-helper (Th)17 responses and impaired Th1 responses compared with healthy controls. CONCLUSION: These findings suggest that the development of CGIFRS may be associated with an abnormally exaggerated host Th17 response, which caused failure to clear the fungal pathogen with refractory fungal infection of mucosal membranes, resulting in chronic tissue inflammation.

18.
Nat Microbiol ; 1: 15023, 2016 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-27572160

RESUMO

Host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. Many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts(1). Host adaptation can potentially progress to host restriction, where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. Host-adapted and host-restricted bacterial clades evolve from within a broader host-promiscuous species and sometimes target different niches within their specialist hosts, such as adapting from a mucosal to a systemic lifestyle. Genome degradation, marked by gene inactivation and deletion, is a key feature of host adaptation, although the triggers initiating genome degradation are not well understood. Here, we show that a chronic systemic non-typhoidal Salmonella infection in an immunocompromised human patient resulted in genome degradation targeting genes that are expendable for a systemic lifestyle. We present a genome-based investigation of a recurrent blood-borne Salmonella enterica serotype Enteritidis (S. Enteritidis) infection covering 15 years in an interleukin-12 ß1 receptor-deficient individual that developed into an asymptomatic chronic infection. The infecting S. Enteritidis harboured a mutation in the mismatch repair gene mutS that accelerated the genomic mutation rate. Phylogenetic analysis and phenotyping of multiple patient isolates provides evidence for a remarkable level of within-host evolution that parallels genome changes present in successful host-restricted bacterial pathogens but never before observed on this timescale. Our analysis identifies common pathways of host adaptation and demonstrates the role that immunocompromised individuals can play in this process.


Assuntos
Adaptação Biológica , Bacteriemia/microbiologia , Interações Hospedeiro-Patógeno , Hospedeiro Imunocomprometido , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Salmonella enteritidis/isolamento & purificação , Evolução Molecular , Deleção de Genes , Variação Genética , Genoma Bacteriano , Humanos , Proteína MutS de Ligação de DNA com Erro de Pareamento/deficiência , Taxa de Mutação , Filogenia , Salmonella enteritidis/classificação , Fatores de Tempo
19.
PLoS One ; 11(5): e0155059, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27167980

RESUMO

The recently described Mucosal Associated Invariant T (MAIT) cells mediate specific recognition of bacterial and fungal vitamin B2 metabolites. As innate T cells, they possess broad effector responses, including IFN- including Iproduction, that are comparable to conventional T cell responses. Immunodeficiencies associated with systemic Th17 deficiency may also be compounded by defects in MAIT immunity. We evaluated Th17 immunity in this innate T cell compartment in primary (AD-HIES) and secondary immunodeficiency (thymoma) patients with conventional Th17 deficiency and susceptibility to fungal and bacterial disease. Our results suggest that MAIT cells are both reduced and functional deficient in STAT3 deficiency and thymoma patients with IL-12/23 autoantibodies. In contrast, thymoma patients without autoantibodies preserved the normal number and functional MAIT cells.


Assuntos
Síndromes de Imunodeficiência/imunologia , Células T Invariáveis Associadas à Mucosa/imunologia , Células Th17/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Citocinas/biossíntese , Feminino , Humanos , Espaço Intracelular/metabolismo , Masculino , Pessoa de Meia-Idade
20.
Nat Microbiol ; 1(3)2016 03.
Artigo em Inglês | MEDLINE | ID: mdl-27127642

RESUMO

Host adaptation is a key factor contributing to the emergence of new bacterial, viral and parasitic pathogens. Many pathogens are considered promiscuous because they cause disease across a range of host species, while others are host-adapted, infecting particular hosts1. Host adaptation can potentially progress to host restriction where the pathogen is strictly limited to a single host species and is frequently associated with more severe symptoms. Host-adapted and host-restricted bacterial clades evolve from within a broader host-promiscuous species and sometimes target different niches within their specialist hosts, such as adapting from a mucosal to a systemic lifestyle. Genome degradation, marked by gene inactivation and deletion, is a key feature of host adaptation, although the triggers initiating genome degradation are not well understood. Here, we show that a chronic systemic non-typhoidal Salmonella infection in an immunocompromised human patient resulted in genome degradation targeting genes that are expendable for a systemic lifestyle. We present a genome-based investigation of a recurrent blood-borne Salmonella enterica serotype Enteritidis (S. Enteritidis) infection covering 15 years in an interleukin (IL)-12 ß-1 receptor-deficient individual that developed into an asymptomatic chronic infection. The infecting S. Enteritidis harbored a mutation in the mismatch repair gene mutS that accelerated the genomic mutation rate. Phylogenetic analysis and phenotyping of multiple patient isolates provides evidence for a remarkable level of within-host evolution that parallels genome changes present in successful host-restricted bacterial pathogens but never before observed on this timescale. Our analysis identifies common pathways of host adaptation and demonstrates the role that immunocompromised individuals can play in this process.


Assuntos
Adaptação Fisiológica/genética , Genoma Bacteriano , Interações Hospedeiro-Patógeno , Hospedeiro Imunocomprometido , Síndromes de Imunodeficiência/complicações , Infecções por Salmonella/microbiologia , Salmonella enteritidis/genética , Adulto , Bacteriemia/microbiologia , Doença Crônica , Evolução Molecular , Especificidade de Hospedeiro , Humanos , Subunidade beta 1 de Receptor de Interleucina-12/deficiência , Subunidade beta 1 de Receptor de Interleucina-12/genética , Mutação , Taxa de Mutação , Infecções por Salmonella/complicações , Salmonella enteritidis/classificação , Salmonella enteritidis/isolamento & purificação , Salmonella enteritidis/patogenicidade , Virulência
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