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1.
Br J Cancer ; 128(2): 161-164, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36599918

RESUMEN

Genomic screening is routinely used to guide the treatment of cancer patients in many countries. However, several multi-layered factors make this effort difficult to deliver within a clinically relevant timeframe. Here we share the learnings from the CRUK-funded Stratified Medicine Programme for advanced NSCLC patients, which could be useful to better plan future studies.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Reino Unido
4.
Nature ; 583(7818): 807-812, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32669708

RESUMEN

The majority of targeted therapies for non-small-cell lung cancer (NSCLC) are directed against oncogenic drivers that are more prevalent in patients with light exposure to tobacco smoke1-3. As this group represents around 20% of all patients with lung cancer, the discovery of stratified medicine options for tobacco-associated NSCLC is a high priority. Umbrella trials seek to streamline the investigation of genotype-based treatments by screening tumours for multiple genomic alterations and triaging patients to one of several genotype-matched therapeutic agents. Here we report the current outcomes of 19 drug-biomarker cohorts from the ongoing National Lung Matrix Trial, the largest umbrella trial in NSCLC. We use next-generation sequencing to match patients to appropriate targeted therapies on the basis of their tumour genotype. The Bayesian trial design enables outcome data from open cohorts that are still recruiting to be reported alongside data from closed cohorts. Of the 5,467 patients that were screened, 2,007 were molecularly eligible for entry into the trial, and 302 entered the trial to receive genotype-matched therapy-including 14 that re-registered to the trial for a sequential trial drug. Despite pre-clinical data supporting the drug-biomarker combinations, current evidence shows that a limited number of combinations demonstrate clinically relevant benefits, which remain concentrated in patients with lung cancers that are associated with minimal exposure to tobacco smoke.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/terapia , Marcadores Genéticos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Terapia Molecular Dirigida , Medicina de Precisión , Fumar/genética , Teorema de Bayes , Carcinoma de Pulmón de Células no Pequeñas/etiología , Protocolos Clínicos , Ensayos Clínicos como Asunto , Estudios de Cohortes , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Pulmonares/etiología , Oncogenes/genética , Selección de Paciente , Humo/efectos adversos , Triaje
5.
Nat Commun ; 10(1): 2176, 2019 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-31092817

RESUMEN

Streptococcus pneumoniae is a common nasopharyngeal colonizer, but can also cause life-threatening invasive diseases such as empyema, bacteremia and meningitis. Genetic variation of host and pathogen is known to play a role in invasive pneumococcal disease, though to what extent is unknown. In a genome-wide association study of human and pathogen we show that human variation explains almost half of variation in susceptibility to pneumococcal meningitis and one-third of variation in severity, identifying variants in CCDC33 associated with susceptibility. Pneumococcal genetic variation explains a large amount of invasive potential (70%), but has no effect on severity. Serotype alone is insufficient to explain invasiveness, suggesting other pneumococcal factors are involved in progression to invasive disease. We identify pneumococcal genes involved in invasiveness including pspC and zmpD, and perform a human-bacteria interaction analysis. These genes are potential candidates for the development of more broadly-acting pneumococcal vaccines.


Asunto(s)
Predisposición Genética a la Enfermedad , Meningitis Neumocócica/genética , Streptococcus pneumoniae/genética , Adulto , Anciano , Proteínas Bacterianas/genética , Femenino , Variación Genética , Genoma Bacteriano/genética , Genoma Humano/genética , Estudio de Asociación del Genoma Completo , Interacciones Huésped-Patógeno/genética , Humanos , Masculino , Meningitis Neumocócica/microbiología , Persona de Mediana Edad , Estudios Prospectivos , Proteínas/genética , Streptococcus pneumoniae/aislamiento & purificación
6.
Nat Commun ; 9(1): 1014, 2018 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-29523850

RESUMEN

Nontyphoidal Salmonella (NTS) is a major cause of bacteraemia in Africa. The disease typically affects HIV-infected individuals and young children, causing substantial morbidity and mortality. Here we present a genome-wide association study (180 cases, 2677 controls) and replication analysis of NTS bacteraemia in Kenyan and Malawian children. We identify a locus in STAT4, rs13390936, associated with NTS bacteraemia. rs13390936 is a context-specific expression quantitative trait locus for STAT4 RNA expression, and individuals carrying the NTS-risk genotype demonstrate decreased interferon-γ (IFNγ) production in stimulated natural killer cells, and decreased circulating IFNγ concentrations during acute NTS bacteraemia. The NTS-risk allele at rs13390936 is associated with protection against a range of autoimmune diseases. These data implicate interleukin-12-dependent IFNγ-mediated immunity as a determinant of invasive NTS disease in African children, and highlight the shared genetic architecture of infectious and autoimmune disease.


Asunto(s)
Enfermedades Autoinmunes/genética , Bacteriemia/epidemiología , Predisposición Genética a la Enfermedad , Factor de Transcripción STAT4/genética , Infecciones por Salmonella/epidemiología , Salmonella/patogenicidad , Adolescente , Alelos , Enfermedades Autoinmunes/epidemiología , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/microbiología , Bacteriemia/genética , Bacteriemia/inmunología , Bacteriemia/microbiología , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Estudios de Seguimiento , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Inmunidad Celular/genética , Lactante , Recién Nacido , Interferón gamma/sangre , Interferón gamma/inmunología , Interferón gamma/metabolismo , Interleucina-12/inmunología , Interleucina-12/metabolismo , Kenia/epidemiología , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Malaui/epidemiología , Masculino , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo/genética , Factores de Riesgo , Salmonella/aislamiento & purificación , Infecciones por Salmonella/genética , Infecciones por Salmonella/inmunología , Infecciones por Salmonella/microbiología
7.
Am J Hum Genet ; 98(6): 1092-1100, 2016 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-27236921

RESUMEN

Bacteremia (bacterial bloodstream infection) is a major cause of illness and death in sub-Saharan Africa but little is known about the role of human genetics in susceptibility. We conducted a genome-wide association study of bacteremia susceptibility in more than 5,000 Kenyan children as part of the Wellcome Trust Case Control Consortium 2 (WTCCC2). Both the blood-culture-proven bacteremia case subjects and healthy infants as controls were recruited from Kilifi, on the east coast of Kenya. Streptococcus pneumoniae is the most common cause of bacteremia in Kilifi and was thus the focus of this study. We identified an association between polymorphisms in a long intergenic non-coding RNA (lincRNA) gene (AC011288.2) and pneumococcal bacteremia and replicated the results in the same population (p combined = 1.69 × 10(-9); OR = 2.47, 95% CI = 1.84-3.31). The susceptibility allele is African specific, derived rather than ancestral, and occurs at low frequency (2.7% in control subjects and 6.4% in case subjects). Our further studies showed AC011288.2 expression only in neutrophils, a cell type that is known to play a major role in pneumococcal clearance. Identification of this novel association will further focus research on the role of lincRNAs in human infectious disease.


Asunto(s)
Bacteriemia/genética , Neumonía Neumocócica/genética , Polimorfismo Genético/genética , ARN Largo no Codificante/genética , Streptococcus pneumoniae/genética , Adolescente , Bacteriemia/microbiología , Bacteriemia/patología , Estudios de Casos y Controles , Niño , Preescolar , Estudio de Asociación del Genoma Completo , Humanos , Lactante , Recién Nacido , Kenia/epidemiología , Neumonía Neumocócica/microbiología , Neumonía Neumocócica/patología , Factores de Riesgo
8.
Lancet Respir Med ; 4(4): 259-71, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-26917434

RESUMEN

BACKGROUND: Effective targeted therapy for sepsis requires an understanding of the heterogeneity in the individual host response to infection. We investigated this heterogeneity by defining interindividual variation in the transcriptome of patients with sepsis and related this to outcome and genetic diversity. METHODS: We assayed peripheral blood leucocyte global gene expression for a prospective discovery cohort of 265 adult patients admitted to UK intensive care units with sepsis due to community-acquired pneumonia and evidence of organ dysfunction. We then validated our findings in a replication cohort consisting of a further 106 patients. We mapped genomic determinants of variation in gene transcription between patients as expression quantitative trait loci (eQTL). FINDINGS: We discovered that following admission to intensive care, transcriptomic analysis of peripheral blood leucocytes defines two distinct sepsis response signatures (SRS1 and SRS2). The presence of SRS1 (detected in 108 [41%] patients in discovery cohort) identifies individuals with an immunosuppressed phenotype that included features of endotoxin tolerance, T-cell exhaustion, and downregulation of human leucocyte antigen (HLA) class II. SRS1 was associated with higher 14 day mortality than was SRS2 (discovery cohort hazard ratio (HR) 2·4, 95% CI 1·3-4·5, p=0·005; validation cohort HR 2·8, 95% CI 1·5-5·1, p=0·0007). We found that a predictive set of seven genes enabled the classification of patients as SRS1 or SRS2. We identified cis-acting and trans-acting eQTL for key immune and metabolic response genes and sepsis response networks. Sepsis eQTL were enriched in endotoxin-induced epigenetic marks and modulated the individual host response to sepsis, including effects specific to SRS group. We identified regulatory genetic variants involving key mediators of gene networks implicated in the hypoxic response and the switch to glycolysis that occurs in sepsis, including HIF1α and mTOR, and mediators of endotoxin tolerance, T-cell activation, and viral defence. INTERPRETATION: Our integrated genomics approach advances understanding of heterogeneity in sepsis by defining subgroups of patients with different immune response states and prognoses, as well as revealing the role of underlying genetic variation. Our findings provide new insights into the pathogenesis of sepsis and create opportunities for a precision medicine approach to enable targeted therapeutic intervention to improve sepsis outcomes. FUNDING: European Commission, Medical Research Council (UK), and the Wellcome Trust.


Asunto(s)
Genómica , Leucocitos/inmunología , Neumonía/complicaciones , Sepsis/genética , Anciano , Infecciones Comunitarias Adquiridas/complicaciones , Infecciones Comunitarias Adquiridas/genética , Infecciones Comunitarias Adquiridas/inmunología , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Heterogeneidad Genética , Variación Genética , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Fenotipo , Neumonía/genética , Neumonía/inmunología , Estudios Prospectivos , Reproducibilidad de los Resultados , Sepsis/etiología , Sepsis/inmunología
9.
Lancet ; 385 Suppl 1: S13, 2015 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-26312835

RESUMEN

BACKGROUND: Non-typhoidal Salmonella (NTS) causes invasive and frequently fatal disease in African children. Existing strategies to prevent, diagnose, and treat NTS disease are inadequate. An improved understanding of the biology of invasive Salmonella infection will facilitate the development of novel NTS control measures. Despite evidence in mice and man showing a clear role for host genetics in NTS susceptibility, there are no published studies investigating host genetic susceptibility to NTS in African populations. METHODS: We conducted a genome-wide association study (SNP Array 6.0, Affymetrix, CA, USA) of NTS bacteraemia in Kenyan children, with replication in Malawian children. We assessed the function of NTS-associated variants in an expression quantitative trait locus (eQTL) dataset of interferon γ (IFNγ) and lipopolysaccharide-stimulated monocytes from 432 healthy European adults. Serum IFNγ (Bio-Plex immunoassay, Bio-Rad Laboratories, CA, USA) in Malawian NTS cases (n=106) during acute disease was correlated with genotype by linear regression. FINDINGS: After whole-genome imputation and quality control, 180 Kenyan cases and 2677 controls were included in an association analysis at 7 951 614 (additive model) and 4 669 537 (genotypic model) loci. After quality control, 143 Malawian cases and 336 controls were included in the replication analysis. An intronic variant in STAT4 was associated (recessive model) with NTS in both Kenyan and Malawian children (Kenya p=5·6 × 10(-9), Malawi p=0·02, combined p=1·4 × 10(-9); odds ratio 7·2, 95% CI 3·8-13·5). The NTS-associated variant was an eQTL for STAT4 expression in IFNγ-stimulated monocytes (p=9·59 × 10(-6)), the NTS risk allele being associated with lower STAT4 expression. In Malawian children with NTS bacteraemia, the same NTS risk allele was associated with lower serum concentrations of IFNγ (p=0·02) at presentation. INTERPRETATION: STAT4 is highly plausible as a susceptibility locus for invasive NTS disease. STAT4 mediates IFNγ release in T cells and natural killer cells in response to interleukin 12 (IL12). Individuals with rare mutations elsewhere in the IL12-IFNγ axis are at risk of disseminated NTS infection. We provide the first evidence, to our knowledge, of a host genetic determinant of NTS disease in African children, and of a STAT4 variant conferring susceptibility to an infectious disease in man. FUNDING: Wellcome Trust.

10.
Clin Infect Dis ; 61(5): 695-703, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-25969530

RESUMEN

BACKGROUND: Sepsis is an increasingly common condition, which continues to be associated with unacceptably high mortality. A large number of association studies have investigated susceptibility to, or mortality from, sepsis for variants in the functionally important immune-related gene MBL2. These studies have largely been underpowered and contradictory. METHODS: We genotyped and analyzed 4 important MBL2 single nucleotide polymorphisms (SNPs; rs5030737, rs1800450, rs1800451, and rs7096206) in 1839 European community-acquired pneumonia (CAP) and peritonitis sepsis cases, and 477 controls from the United Kingdom. We analyzed the following predefined subgroups and outcomes: 28-day and 6 month mortality from sepsis due to CAP or peritonitis combined, 28-day mortality from CAP sepsis, peritonitis sepsis, pneumococcal sepsis or sepsis in younger patients, and susceptibility to CAP sepsis or pneumococcal sepsis in the United Kingdom. RESULTS: There were no significant associations (all P-values were greater than .05 after correction for multiple testing) between MBL2 genotypes and any of our predefined analyses. CONCLUSIONS: In this large, well-defined cohort of immune competent adult patients, no associations between MBL2 genotype and sepsis susceptibility or outcome were identified.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Lectina de Unión a Manosa/genética , Sepsis/epidemiología , Sepsis/genética , Adulto , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/genética
11.
Lancet Respir Med ; 3(1): 53-60, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25533491

RESUMEN

BACKGROUND: Sepsis continues to be a major cause of death, disability, and health-care expenditure worldwide. Despite evidence suggesting that host genetics can influence sepsis outcomes, no specific loci have yet been convincingly replicated. The aim of this study was to identify genetic variants that influence sepsis survival. METHODS: We did a genome-wide association study in three independent cohorts of white adult patients admitted to intensive care units with sepsis, severe sepsis, or septic shock (as defined by the International Consensus Criteria) due to pneumonia or intra-abdominal infection (cohorts 1-3, n=2534 patients). The primary outcome was 28 day survival. Results for the cohort of patients with sepsis due to pneumonia were combined in a meta-analysis of 1553 patients from all three cohorts, of whom 359 died within 28 days of admission to the intensive-care unit. The most significantly associated single nucleotide polymorphisms (SNPs) were genotyped in a further 538 white patients with sepsis due to pneumonia (cohort 4), of whom 106 died. FINDINGS: In the genome-wide meta-analysis of three independent pneumonia cohorts (cohorts 1-3), common variants in the FER gene were strongly associated with survival (p=9·7 × 10(-8)). Further genotyping of the top associated SNP (rs4957796) in the additional cohort (cohort 4) resulted in a combined p value of 5·6 × 10(-8) (odds ratio 0·56, 95% CI 0·45-0·69). In a time-to-event analysis, each allele reduced the mortality over 28 days by 44% (hazard ratio for death 0·56, 95% CI 0·45-0·69; likelihood ratio test p=3·4 × 10(-9), after adjustment for age and stratification by cohort). Mortality was 9·5% in patients carrying the CC genotype, 15·2% in those carrying the TC genotype, and 25·3% in those carrying the TT genotype. No significant genetic associations were identified when patients with sepsis due to pneumonia and intra-abdominal infection were combined. INTERPRETATION: We have identified common variants in the FER gene that associate with a reduced risk of death from sepsis due to pneumonia. The FER gene and associated molecular pathways are potential novel targets for therapy or prevention and candidates for the development of biomarkers for risk stratification. FUNDING: European Commission and the Wellcome Trust.


Asunto(s)
Estudio de Asociación del Genoma Completo/estadística & datos numéricos , Neumonía/complicaciones , Proteínas Tirosina Quinasas/genética , Sepsis/etiología , Sepsis/genética , Estudios de Cohortes , Femenino , Marcadores Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Humanos , Masculino , Persona de Mediana Edad , Análisis de Supervivencia
12.
J Infect Dis ; 209(7): 1028-31, 2014 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-23997235

RESUMEN

Interferon-inducible transmembrane proteins 1, 2, and 3 (IFITM 1,2, and 3) are viral restriction factors that mediate cellular resistance to several viruses. We have genotyped a possible splice-site altering single-nucleotide polymorphism (rs12252) in the IFITM3 gene in 34 patients with H1N1 influenza and severe pneumonia, and >5000 individuals comprising patients with community-acquired mild lower respiratory tract infection and matched controls of Caucasian ancestry. We found evidence of an association between rs12252 rare allele homozygotes and susceptibility to mild influenza (in patients attending primary care) but could not confirm a previously reported association between this single-nucleotide polymorphism and susceptibility to severe H1N1 infection.


Asunto(s)
Infecciones Comunitarias Adquiridas/epidemiología , Predisposición Genética a la Enfermedad , Proteínas de la Membrana/genética , Proteínas de Unión al ARN/genética , Infecciones del Sistema Respiratorio/epidemiología , Virosis/epidemiología , Adulto , Infecciones Comunitarias Adquiridas/genética , Femenino , Humanos , Masculino , Polimorfismo de Nucleótido Simple , Infecciones del Sistema Respiratorio/genética , Virosis/genética
13.
J Biol Chem ; 286(2): 1341-53, 2011 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-20966070

RESUMEN

Innate immune receptors detect microbial pathogens and subsequently activate adaptive immune responses to combat pathogen invasion. MyD88 is a key adaptor molecule in both Toll-like receptor (TLR) and IL-1 receptor superfamily signaling pathways. This is illustrated by the fact that human individuals carrying rare, naturally occurring MYD88 point mutations suffer from reoccurring life-threatening infections. Here we analyzed the functional properties of six reported non-synonymous single nucleotide polymorphisms of MYD88 in an in vitro cellular system. Two variants found in the MyD88 death domain, S34Y and R98C, showed severely reduced NF-κB activation due to reduced homo-oligomerization and IRAK4 interaction. Structural modeling highlights Ser-34 and Arg-98 as residues important for the assembly of the Myddosome, a death domain (DD) post-receptor complex involving the DD of MyD88, IRAK4, and IRAK2 or IRAK1. Using S34Y and R98C as functional probes, our data show that MyD88 homo-oligomerization and IRAK4 interaction is modulated by the MyD88 TIR and IRAK4 kinase domain, demonstrating the functional importance of non-DD regions not observed in a recent Myddosome crystal structure. The differential interference of S34Y and R98C with some (IL-1 receptor, TLR2, TLR4, TLR5, and TLR7) but not all (TLR9) MyD88-dependent signaling pathways also suggests that receptor specificities exist at the level of the Myddosome. Given their detrimental effect on signaling, it is not surprising that our epidemiological analysis in several case-control studies confirms that S34Y and R98C are rare variants that may drastically contribute to susceptibility to infection in only few individuals.


Asunto(s)
Variación Genética , Infecciones/genética , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Factor 88 de Diferenciación Mieloide , Transducción de Señal/inmunología , Cristalografía , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Infecciones/inmunología , Infecciones/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/inmunología , Modelos Químicos , Factor 88 de Diferenciación Mieloide/química , Factor 88 de Diferenciación Mieloide/genética , Factor 88 de Diferenciación Mieloide/metabolismo , Fenotipo , Polimorfismo de Nucleótido Simple , Estructura Terciaria de Proteína , Relación Estructura-Actividad
14.
J Biol Chem ; 285(47): 36486-94, 2010 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-20843814

RESUMEN

The innate immune system employs Toll-like receptors (TLRs) for the detection of invading microorganisms based on distinct molecular patterns. For example, TLR9 is activated by microbial DNA and also by short therapeutic CpG-containing oligonucleotides (CpG-ODN). TLR9 activation leads to the production of interferons and the priming of humoral adaptive immune responses. Unfortunately, the principles of ligand recognition by TLR9 are poorly understood, and genetic variants of TLR9, which may affect its function, have not been characterized systematically on the molecular level. We therefore sought to functionally characterize reported single nucleotide polymorphisms of TLR9 in the HEK293 model system. We discovered that two variants, P99L and M400I, are associated with altered receptor function regarding NF-κB activation and cytokine induction. Our investigations show that for the most functionally impaired variant, P99L, the ability to respond to physiological and therapeutic TLR9 ligands is severely compromised. However, CpG-ODN binding is normal. CpG-ODN recognition by TLR9 thus appears to involve two separate events, CpG-ODN binding and sensing. Our studies highlight Pro-99 as a residue important for the latter process. In genotyping studies, we confirmed that both M400I (rs41308230) and P99L (rs5743844) are relatively rare variants of TLR9. Our data add rs41308230 and rs5743844 to the list of functionally important TLR variants and warrant further research into their relevance for infectious disease susceptibility or responsiveness to CpG-ODN-based therapies.


Asunto(s)
Mutación/genética , Oligodesoxirribonucleótidos/farmacología , Polimorfismo de Nucleótido Simple/genética , Receptor Toll-Like 9/genética , Western Blotting , Células Cultivadas , Técnica del Anticuerpo Fluorescente , Genotipo , Humanos , Inmunoprecipitación , Riñón/citología , Riñón/metabolismo , Luciferasas/metabolismo , Mutagénesis Sitio-Dirigida , FN-kappa B/genética , FN-kappa B/metabolismo , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Receptor Toll-Like 9/metabolismo
15.
PLoS Pathog ; 6: e1000979, 2010 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-20617178

RESUMEN

Leprosy is an infectious disease caused by the obligate intracellular pathogen Mycobacterium leprae and remains endemic in many parts of the world. Despite several major studies on susceptibility to leprosy, few genomic loci have been replicated independently. We have conducted an association analysis of more than 1,500 individuals from different case-control and family studies, and observed consistent associations between genetic variants in both TLR1 and the HLA-DRB1/DQA1 regions with susceptibility to leprosy (TLR1 I602S, case-control P = 5.7 x 10(-8), OR = 0.31, 95% CI = 0.20-0.48, and HLA-DQA1 rs1071630, case-control P = 4.9 x 10(-14), OR = 0.43, 95% CI = 0.35-0.54). The effect sizes of these associations suggest that TLR1 and HLA-DRB1/DQA1 are major susceptibility genes in susceptibility to leprosy. Further population differentiation analysis shows that the TLR1 locus is extremely differentiated. The protective dysfunctional 602S allele is rare in Africa but expands to become the dominant allele among individuals of European descent. This supports the hypothesis that this locus may be under selection from mycobacteria or other pathogens that are recognized by TLR1 and its co-receptors. These observations provide insight into the long standing host-pathogen relationship between human and mycobacteria and highlight the key role of the TLR pathway in infectious diseases.


Asunto(s)
Predisposición Genética a la Enfermedad/genética , Antígenos HLA-DR/genética , Lepra/genética , Receptor Toll-Like 1/genética , Frecuencia de los Genes , Estudio de Asociación del Genoma Completo , Antígenos HLA-DQ/genética , Cadenas alfa de HLA-DQ , Cadenas HLA-DRB1 , Humanos , Lepra/inmunología , Mycobacterium leprae/inmunología , Receptor Toll-Like 1/inmunología
16.
N Engl J Med ; 362(22): 2092-101, 2010 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-20484391

RESUMEN

BACKGROUND: The interleukin-2-mediated immune response is critical for host defense against infectious pathogens. Cytokine-inducible SRC homology 2 (SH2) domain protein (CISH), a suppressor of cytokine signaling, controls interleukin-2 signaling. METHODS: Using a case-control design, we tested for an association between CISH polymorphisms and susceptibility to major infectious diseases (bacteremia, tuberculosis, and severe malaria) in blood samples from 8402 persons in Gambia, Hong Kong, Kenya, Malawi, and Vietnam. We had previously tested 20 other immune-related genes in one or more of these sample collections. RESULTS: We observed associations between variant alleles of multiple CISH polymorphisms and increased susceptibility to each infectious disease in each of the study populations. When all five single-nucleotide polymorphisms (SNPs) (at positions -639, -292, -163, +1320, and +3415 [all relative to CISH]) within the CISH-associated locus were considered together in a multiple-SNP score, we found an association between CISH genetic variants and susceptibility to bacteremia, malaria, and tuberculosis (P=3.8x10(-11) for all comparisons), with -292 accounting for most of the association signal (P=4.58x10(-7)). Peripheral-blood mononuclear cells obtained from adult subjects carrying the -292 variant, as compared with wild-type cells, showed a muted response to the stimulation of interleukin-2 production--that is, 25 to 40% less CISH expression. CONCLUSIONS: Variants of CISH are associated with susceptibility to diseases caused by diverse infectious pathogens, suggesting that negative regulators of cytokine signaling have a role in immunity against various infectious diseases. The overall risk of one of these infectious diseases was increased by at least 18% among persons carrying the variant CISH alleles.


Asunto(s)
Bacteriemia/genética , Predisposición Genética a la Enfermedad , Malaria/genética , Polimorfismo de Nucleótido Simple , Proteínas Supresoras de la Señalización de Citocinas/genética , Tuberculosis/genética , Adulto , Estudios de Casos y Controles , Niño , Expresión Génica , Genotipo , Humanos , Interleucina-2/fisiología , Desequilibrio de Ligamiento , Oportunidad Relativa , Riesgo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo
17.
J Immunol ; 184(6): 3025-32, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20164415

RESUMEN

Signals elicited by TLRs following the detection of microbes are integrated and diversified by a group of four cytoplasmic adaptor molecules featuring an evolutionarily conserved Toll/IL-1R signaling domain. Single nucleotide polymorphisms (SNPs) in TLRs and their adaptor molecules have been shown to influence susceptibility to a range of infectious and other diseases. The adaptor MyD88 adaptor-like (Mal)/Toll/IL-1R-containing adaptor protein is involved in TLR2 and 4 signal transduction by recruiting another adaptor molecule, MyD88, to the plasma membrane. In this study, we used naturally occurring variants of Mal as tools to study the molecular biology of Mal in more detail in cellular model systems and to thereby identify functionally interesting variants whose corresponding nonsynonymous SNPs might be of further epidemiological interest. Of seven reported variants for Mal, we found Mal D96N associated with reduced NF-kappaB signaling and cytokine production after overexpression in HEK293 and Huh-7 cells. The D96N mutation prevented Mal from recruiting its signaling partner MyD88 to the plasma membrane and altered posttranslational modification of Mal. These findings led us to investigate the frequency of heterozygosity for the corresponding SNP rs8177400 in a Caucasian case-control study on the etiology of lymphoma, a disease in which TLRs have been implicated. Although rs8177400 did not modify lymphoma risk in general, its frequency of heterozygosity was accurately determined to 0.97%. Our data add rs8177400 (D96N) to the list of functionally important variants of Mal and warrant further research into its immunological, epidemiological, and diagnostic relevance.


Asunto(s)
Variación Genética/inmunología , Glicoproteínas de Membrana/deficiencia , Glicoproteínas de Membrana/genética , Factor 88 de Diferenciación Mieloide , Procesamiento Proteico-Postraduccional/inmunología , Receptores de Interleucina-1/deficiencia , Receptores de Interleucina-1/genética , Transducción de Señal/genética , Transducción de Señal/inmunología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Asparagina/genética , Ácido Aspártico/genética , Estudios de Casos y Controles , Línea Celular Transformada , Línea Celular Tumoral , Predisposición Genética a la Enfermedad/epidemiología , Humanos , Inmunofenotipificación , Glicoproteínas de Membrana/fisiología , Persona de Mediana Edad , Estudios Multicéntricos como Asunto , Factor 88 de Diferenciación Mieloide/fisiología , FN-kappa B/metabolismo , Mutación Puntual/inmunología , Procesamiento Proteico-Postraduccional/genética , Transporte de Proteínas/genética , Transporte de Proteínas/inmunología , Receptores de Interleucina-1/fisiología
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