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1.
Cell ; 163(2): 354-66, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26451485

RESUMO

Infections have been proposed as initiating factors for inflammatory disorders; however, identifying associations between defined infectious agents and the initiation of chronic disease has remained elusive. Here, we report that a single acute infection can have dramatic and long-term consequences for tissue-specific immunity. Following clearance of Yersinia pseudotuberculosis, sustained inflammation and associated lymphatic leakage in the mesenteric adipose tissue deviates migratory dendritic cells to the adipose compartment, thereby preventing their accumulation in the mesenteric lymph node. As a consequence, canonical mucosal immune functions, including tolerance and protective immunity, are persistently compromised. Post-resolution of infection, signals derived from the microbiota maintain inflammatory mesentery remodeling and consequently, transient ablation of the microbiota restores mucosal immunity. Our results indicate that persistent disruption of communication between tissues and the immune system following clearance of an acute infection represents an inflection point beyond which tissue homeostasis and immunity is compromised for the long-term. VIDEO ABSTRACT.


Assuntos
Microbioma Gastrointestinal , Doenças do Sistema Imunitário/microbiologia , Doenças do Sistema Imunitário/patologia , Doenças Linfáticas/patologia , Infecções por Yersinia pseudotuberculosis/imunologia , Yersinia pseudotuberculosis/fisiologia , Movimento Celular , Doença Crônica , Células Dendríticas/patologia , Feminino , Humanos , Doenças Linfáticas/microbiologia , Tecido Linfoide/imunologia , Tecido Linfoide/patologia , Masculino , Mesentério/imunologia , Mesentério/patologia , Organismos Livres de Patógenos Específicos , Infecções por Yersinia pseudotuberculosis/patologia
2.
J Allergy Clin Immunol ; 152(6): 1619-1633.e11, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37659505

RESUMO

BACKGROUND: Chronic granulomatous disease (CGD) is caused by defects in any 1 of the 6 subunits forming the nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2), leading to severely reduced or absent phagocyte-derived reactive oxygen species production. Almost 50% of patients with CGD have inflammatory bowel disease (CGD-IBD). While conventional IBD therapies can treat CGD-IBD, their benefits must be weighed against the risk of infection. Understanding the impact of NOX2 defects on the intestinal microbiota may lead to the identification of novel CGD-IBD treatments. OBJECTIVE: We sought to identify microbiome and metabolome signatures that can distinguish individuals with CGD and CGD-IBD. METHODS: We conducted a cross-sectional observational study of 79 patients with CGD, 8 pathogenic variant carriers, and 19 healthy controls followed at the National Institutes of Health Clinical Center. We profiled the intestinal microbiome (amplicon sequencing) and stool metabolome, and validated our findings in a second cohort of 36 patients with CGD recruited through the Primary Immune Deficiency Treatment Consortium. RESULTS: We identified distinct intestinal microbiome and metabolome profiles in patients with CGD compared to healthy individuals. We observed enrichment for Erysipelatoclostridium spp, Sellimonas spp, and Lachnoclostridium spp in CGD stool samples. Despite differences in bacterial alpha and beta diversity between the 2 cohorts, several taxa correlated significantly between both cohorts. We further demonstrated that patients with CGD-IBD have a distinct microbiome and metabolome profile compared to patients without CGD-IBD. CONCLUSION: Intestinal microbiome and metabolome signatures distinguished patients with CGD and CGD-IBD, and identified potential biomarkers and therapeutic targets.


Assuntos
Microbioma Gastrointestinal , Doença Granulomatosa Crônica , Doenças Inflamatórias Intestinais , Humanos , Doença Granulomatosa Crônica/genética , NADPH Oxidases , Estudos Transversais
3.
Hepatology ; 73(3): 1088-1104, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32557834

RESUMO

BACKGROUND AND AIMS: Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), caused by autoimmune regulator (AIRE) mutations, manifests with chronic mucocutaneous candidiasis (CMC) and multisystem autoimmunity, most often hypoparathyroidism (HP) and adrenal insufficiency (AI). European cohorts previously reported a ~10% prevalence of APECED-associated hepatitis (APAH) with presentations ranging from asymptomatic laboratory derangements to fatal fulminant hepatic failure. Herein, we characterized APAH in a large APECED cohort from the Americas. APPROACH AND RESULTS: Forty-five consecutive patients with APECED were evaluated (2013-2015) at the National Institutes of Health (NIH; NCT01386437). Hepatology consultation assessed hepatic and autoimmune biomarkers and liver ultrasound in all patients. Liver biopsies evaluated autoimmune features and fibrosis. The 16S ribosomal RNA (rRNA) sequencing was performed in 35 patients' stools (12 with and 23 without APAH). Among 43 evaluable patients, 18 (42%) had APAH; in 33.3% of those with APAH, APAH occurred before developing classic APECED diagnostic criteria. At APAH diagnosis, the median age was 7.8 years, and patients manifested with aminotransferase elevation and/or hyperbilirubinemia. All patients with APAH were in clinical remission during their NIH evaluation while receiving immunomodulatory treatment. We found no difference in age, sex, or prevalence of CMC, AI, or HP between patients with or without APAH. Autoantibody positivity against aromatic L-amino acid decarboxylase, cytochrome P450 family 1 subfamily A member 2, histidine decarboxylase (HDC), bactericidal/permeability-increasing fold-containing B1, tryptophan hydroxlase, and 21-hydroxylase (21-OH), and the homozygous c.967_979del13 AIRE mutation were associated with APAH development. Classical serological biomarkers of autoimmune hepatitis (AIH) were only sporadically positive. AIH-like lymphoplasmacytic inflammation with mild fibrosis was the predominant histological feature. Stool microbiome analysis found Slackia and Acidaminococcus in greater abundance in patients with APAH. CONCLUSIONS: APAH is more common than previously described, may present early before classic APECED manifestations, and most often manifests with milder, treatment-responsive disease. Several APECED-associated autoantibodies, but not standard AIH-associated biomarkers, correlate with APAH.


Assuntos
Hepatite Autoimune/etiologia , Poliendocrinopatias Autoimunes/complicações , Adolescente , Adulto , América , Autoanticorpos/imunologia , Biomarcadores/sangue , Biópsia , Feminino , Deleção de Genes , Hepatite Autoimune/patologia , Hepatite Autoimune/terapia , Humanos , Imunoterapia , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Poliendocrinopatias Autoimunes/genética , Poliendocrinopatias Autoimunes/patologia , Poliendocrinopatias Autoimunes/terapia , Adulto Jovem
4.
Proc Natl Acad Sci U S A ; 116(45): 22764-22773, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31636194

RESUMO

Neospora caninum, a cyst-forming apicomplexan parasite, is a leading cause of neuromuscular diseases in dogs as well as fetal abortion in cattle worldwide. The importance of the domestic and sylvatic life cycles of Neospora, and the role of vertical transmission in the expansion and transmission of infection in cattle, is not sufficiently understood. To elucidate the population genomics of Neospora, we genotyped 50 isolates collected worldwide from a wide range of hosts using 19 linked and unlinked genetic markers. Phylogenetic analysis and genetic distance indices resolved a single genotype of N. caninum Whole-genome sequencing of 7 isolates from 2 different continents identified high linkage disequilibrium, significant structural variation, but only limited polymorphism genome-wide, with only 5,766 biallelic single nucleotide polymorphisms (SNPs) total. Greater than half of these SNPs (∼3,000) clustered into 6 distinct haploblocks and each block possessed limited allelic diversity (with only 4 to 6 haplotypes resolved at each cluster). Importantly, the alleles at each haploblock had independently segregated across the strains sequenced, supporting a unisexual expansion model that is mosaic at 6 genomic blocks. Integrating seroprevalence data from African cattle, our data support a global selective sweep of a highly inbred livestock pathogen that originated within European dairy stock and expanded transcontinentally via unisexual mating and vertical transmission very recently, likely the result of human activities, including recurrent migration, domestication, and breed development of bovid and canid hosts within similar proximities.


Assuntos
Genoma , Interações Hospedeiro-Parasita , Neospora/genética , Animais , Bovinos , Genótipo , Recombinação Genética
5.
Nature ; 520(7545): 104-8, 2015 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-25539086

RESUMO

The skin represents the primary interface between the host and the environment. This organ is also home to trillions of microorganisms that play an important role in tissue homeostasis and local immunity. Skin microbial communities are highly diverse and can be remodelled over time or in response to environmental challenges. How, in the context of this complexity, individual commensal microorganisms may differentially modulate skin immunity and the consequences of these responses for tissue physiology remains unclear. Here we show that defined commensals dominantly affect skin immunity and identify the cellular mediators involved in this specification. In particular, colonization with Staphylococcus epidermidis induces IL-17A(+) CD8(+) T cells that home to the epidermis, enhance innate barrier immunity and limit pathogen invasion. Commensal-specific T-cell responses result from the coordinated action of skin-resident dendritic cell subsets and are not associated with inflammation, revealing that tissue-resident cells are poised to sense and respond to alterations in microbial communities. This interaction may represent an evolutionary means by which the skin immune system uses fluctuating commensal signals to calibrate barrier immunity and provide heterologous protection against invasive pathogens. These findings reveal that the skin immune landscape is a highly dynamic environment that can be rapidly and specifically remodelled by encounters with defined commensals, findings that have profound implications for our understanding of tissue-specific immunity and pathologies.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Pele/imunologia , Pele/microbiologia , Simbiose/imunologia , Animais , Antígenos de Bactérias/imunologia , Linfócitos T CD8-Positivos/citologia , Células Dendríticas/citologia , Humanos , Imunidade Inata/imunologia , Interleucina-17/imunologia , Células de Langerhans/citologia , Células de Langerhans/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Primatas , Pele/citologia , Staphylococcus epidermidis/imunologia
6.
J Infect Dis ; 221(Suppl 4): S383-S388, 2020 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-31784761

RESUMO

Viruses in the genus Henipavirus encompass 2 highly pathogenic emerging zoonotic pathogens, Hendra virus (HeV) and Nipah virus (NiV). Despite the impact on human health, there is currently limited full-genome sequence information available for henipaviruses. This lack of full-length genomes hampers our ability to understand the molecular drivers of henipavirus emergence. Furthermore, rapidly deployable viral genome sequencing can be an integral part of outbreak response and epidemiological investigations to study transmission chains. In this study, we describe the development of a reverse-transcription, long-range polymerase chain reaction (LRPCR) assay for efficient genome amplification of NiV, HeV, and a related non-pathogenic henipavirus, Cedar virus (CedPV). We then demonstrated the utility of our method by amplifying partial viral genomes from 6 HeV-infected tissue samples from Syrian hamsters and 4 tissue samples from a NiV-infected African green monkey with viral loads as low as 52 genome copies/mg. We subsequently sequenced the amplified genomes on the portable Oxford Nanopore MinION platform and analyzed the data using a newly developed field-deployable bioinformatic pipeline. Our LRPCR assay allows amplification and sequencing of 2 or 4 amplicons in semi-nested reactions. Coupled with an easy-to-use bioinformatics pipeline, this method is particularly useful in the field during outbreaks in resource-poor environments.


Assuntos
Henipavirus/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Reação em Cadeia da Polimerase/métodos , Genoma Viral , RNA Viral
7.
BMC Bioinformatics ; 21(1): 378, 2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32883210

RESUMO

BACKGROUND: The improvements in genomics methods coupled with readily accessible high-throughput sequencing have contributed to our understanding of microbial species, metagenomes, infectious diseases and more. To maximize the impact of these genomics studies, it is important that data from biological samples will become publicly available with standardized metadata. The availability of data at public archives provides the hope that greater insights could be obtained through integration with multi-omics data, reproducibility of published studies, or meta-analyses of large diverse datasets. These datasets should include a description of the host, organism, environmental source of the specimen, spatial-temporal information and other relevant metadata, but unfortunately these attributes are often missing and when present, they show inconsistencies in the use of metadata standards and ontologies. RESULTS: METAGENOTE ( https://metagenote.niaid.nih.gov ) is a web portal that greatly facilitates the annotation of samples from genomic studies and streamlines the submission process of sequencing files and metadata to the Sequence Read Archive (SRA) (Leinonen R, et al, Nucleic Acids Res, 39:D19-21, 2011) for public access. This platform offers a wide selection of packages for different types of biological and experimental studies with a special emphasis on the standardization of metadata reporting. These packages follow the guidelines from the MIxS standards developed by the Genomics Standard Consortium (GSC) and adopted by the three partners of the International Nucleotides Sequencing Database Collaboration (INSDC) (Cochrane G, et al, Nucleic Acids Res, 44:D48-50, 2016) - National Center for Biotechnology Information (NCBI), European Bioinformatics Institute (EBI) and the DNA Data Bank of Japan (DDBJ). METAGENOTE then compiles, validates and manages the submission through an easy-to-use web interface minimizing submission errors and eliminating the need for submitting sequencing files via a separate file transfer mechanism. CONCLUSIONS: METAGENOTE is a public resource that focuses on simplifying the annotation and submission process of data with its corresponding metadata. Users of METAGENOTE will benefit from the easy to use annotation interface but most importantly will be encouraged to publish metadata following standards and ontologies that make the public data available for reuse.


Assuntos
Genômica/métodos , Interface Usuário-Computador , Animais , Bases de Dados Genéticas , Humanos
8.
J Infect Dis ; 219(12): 1963-1968, 2019 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-30721997

RESUMO

Lactoferrin modulates mucosal immunity and targets mechanisms contributing to inflammation during human immunodeficiency virus disease. A randomized placebo-controlled crossover clinical trial of recombinant human (rh) lactoferrin was conducted among 54 human immunodeficiency virus-infected participants with viral suppression. Outcomes were tolerability, inflammatory, and immunologic measures, and the intestinal microbiome. The median age was 51 years, and the median CD4+ cell count was 651/µL. Adherence and adverse events did not differ between rh-lactoferrin and placebo. There was no significant effect on plasma interleukin-6 or D-dimer levels, nor on monocyte/T-cell activation, mucosal integrity, or intestinal microbiota diversity. Oral administration of rh-lactoferrin was safe but did not reduce inflammation and immune activation. Clinical Trials Registration: NCT01830595.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Lactoferrina/uso terapêutico , Ativação Linfocitária/efeitos dos fármacos , Proteínas Recombinantes de Fusão/uso terapêutico , Terapia Antirretroviral de Alta Atividade/métodos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Feminino , HIV/efeitos dos fármacos , HIV/imunologia , Infecções por HIV/virologia , Humanos , Imunidade nas Mucosas/imunologia , Inflamação/tratamento farmacológico , Inflamação/virologia , Interleucina-6/metabolismo , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Carga Viral/efeitos dos fármacos
9.
Bioinformatics ; 34(8): 1411-1413, 2018 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-29028892

RESUMO

Motivation: Widespread interest in the study of the microbiome has resulted in data proliferation and the development of powerful computational tools. However, many scientific researchers lack the time, training, or infrastructure to work with large datasets or to install and use command line tools. Results: The National Institute of Allergy and Infectious Diseases (NIAID) has created Nephele, a cloud-based microbiome data analysis platform with standardized pipelines and a simple web interface for transforming raw data into biological insights. Nephele integrates common microbiome analysis tools as well as valuable reference datasets like the healthy human subjects cohort of the Human Microbiome Project (HMP). Nephele is built on the Amazon Web Services cloud, which provides centralized and automated storage and compute capacity, thereby reducing the burden on researchers and their institutions. Availability and implementation: https://nephele.niaid.nih.gov and https://github.com/niaid/Nephele. Contact: darrell.hurt@nih.gov.


Assuntos
Computação em Nuvem , Biologia Computacional/métodos , Microbiota/genética , Software , Humanos , Metagenômica/métodos , Análise de Sequência de DNA/métodos , Análise de Sequência de RNA
10.
J Clin Microbiol ; 55(2): 457-469, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27903602

RESUMO

The emergence and spread of drug-resistant Mycobacterium tuberculosis (DR-TB) are critical global health issues. Eastern Europe has some of the highest incidences of DR-TB, particularly multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB. To better understand the genetic composition and evolution of MDR- and XDR-TB in the region, we sequenced and analyzed the genomes of 138 M. tuberculosis isolates from 97 patients sampled between 2010 and 2013 in Minsk, Belarus. MDR and XDR-TB isolates were significantly more likely to belong to the Beijing lineage than to the Euro-American lineage, and known resistance-conferring loci accounted for the majority of phenotypic resistance to first- and second-line drugs in MDR and XDR-TB. Using a phylogenomic approach, we estimated that the majority of MDR-TB was due to the recent transmission of already-resistant M. tuberculosis strains rather than repeated de novo evolution of resistance within patients, while XDR-TB was acquired through both routes. Longitudinal sampling of M. tuberculosis from 34 patients with treatment failure showed that most strains persisted genetically unchanged during treatment or acquired resistance to fluoroquinolones. HIV+ patients were significantly more likely to have multiple infections over time than HIV- patients, highlighting a specific need for careful infection control in these patients. These data provide a better understanding of the genomic composition, transmission, and evolution of MDR- and XDR-TB in Belarus and will enable improved diagnostics, treatment protocols, and prognostic decision-making.


Assuntos
Evolução Molecular , Genoma Bacteriano , Mycobacterium tuberculosis/genética , Análise de Sequência de DNA , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Antituberculosos/farmacologia , Transmissão de Doença Infecciosa , Genótipo , Humanos , Estudos Longitudinais , Epidemiologia Molecular , República de Belarus/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/transmissão
11.
Malar J ; 15: 30, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26791272

RESUMO

BACKGROUND: The rodent malaria parasite Plasmodium yoelii is an important animal model for studying host-parasite interaction and molecular basis of malaria pathogenesis. Although a draft genome of P. yoelii yoelii YM is available, and RNA sequencing (RNA-seq) data for several rodent malaria species (RMP) were reported recently, variations in coding regions and structure of mRNA transcript are likely present between different parasite strains or subspecies. Sequencing of cDNA libraries from additional parasite strains/subspecies will help improve the gene models and genome annotation. METHODS: Here two directional cDNA libraries from mixed blood stages of a subspecies of P. yoelii (P. y. nigeriensis NSM) with or without mefloquine (MQ) treatment were sequenced, and the sequence reads were compared to the genome and cDNA sequences of P. y. yoelii YM in public databases to investigate single nucleotide polymorphisms (SNPs) in coding regions, variations in intron-exon structure and differential splicing between P. yoelii subspecies, and variations in gene expression under MQ pressure. RESULTS: Approximately 56 million of 100 bp paired-end reads were obtained, providing an average of ~225-fold coverage for the coding regions. Comparison of the sequence reads to the YM genome revealed introns in 5' and 3' untranslated regions (UTRs), altered intron/exon boundaries, alternative splicing, overlapping sense-antisense reads, and potentially new transcripts. Interestingly, comparison of the NSM RNA-seq reads obtained here with those of YM discovered differentially spliced introns; e.g., spliced introns in one subspecies but not the other. Alignment of the NSM cDNA sequences to the YM genome sequence also identified ~84,000 SNPs between the two parasites. CONCLUSION: The discoveries of UTR introns and differentially spliced introns between P. yoelii subspecies raise interesting questions on the potential role of these introns in regulating gene expression and evolution of malaria parasites.


Assuntos
Processamento Alternativo/genética , Íntrons/genética , Plasmodium yoelii/genética , RNA Antissenso/genética , Genoma de Protozoário/genética , Malária/parasitologia , Polimorfismo de Nucleotídeo Único/genética
12.
BMC Genomics ; 15: 636, 2014 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-25073905

RESUMO

BACKGROUND: Genome sequencing of Anopheles gambiae was completed more than ten years ago and has accelerated research on malaria transmission. However, annotation needs to be refined and verified experimentally, as most predicted transcripts have been identified by comparative analysis with genomes from other species. The mosquito midgut-the first organ to interact with Plasmodium parasites-mounts effective antiplasmodial responses that limit parasite survival and disease transmission. High-throughput Illumina sequencing of the midgut transcriptome was used to identify new genes and transcripts, contributing to the refinement of An. gambiae genome annotation. RESULTS: We sequenced ~223 million reads from An. gambiae midgut cDNA libraries generated from susceptible (G3) and refractory (L35) mosquito strains. Mosquitoes were infected with either Plasmodium berghei or Plasmodium falciparum, and midguts were collected after the first or second Plasmodium infection. In total, 22,889 unique midgut transcript models were generated from both An. gambiae strain sequences combined, and 76% are potentially novel. Of these novel transcripts, 49.5% aligned with annotated genes and appear to be isoforms or pre-mRNAs of reference transcripts, while 50.5% mapped to regions between annotated genes and represent novel intergenic transcripts (NITs). Predicted models were validated for midgut expression using qRT-PCR and microarray analysis, and novel isoforms were confirmed by sequencing predicted intron-exon boundaries. Coding potential analysis revealed that 43% of total midgut transcripts appear to be long non-coding RNA (lncRNA), and functional annotation of NITs showed that 68% had no homology to current databases from other species. Reads were also analyzed using de novo assembly and predicted transcripts compared with genome mapping-based models. Finally, variant analysis of G3 and L35 midgut transcripts detected 160,742 variants with respect to the An. gambiae PEST genome, and 74% were new variants. Intergenic transcripts had a higher frequency of variation compared with non-intergenic transcripts. CONCLUSION: This in-depth Illumina sequencing and assembly of the An. gambiae midgut transcriptome doubled the number of known transcripts and tripled the number of variants known in this mosquito species. It also revealed existence of a large number of lncRNA and opens new possibilities for investigating the biological function of many newly discovered transcripts.


Assuntos
Anopheles/genética , Mucosa Intestinal/metabolismo , Anotação de Sequência Molecular/métodos , Transcriptoma , Animais , Anopheles/embriologia , Anopheles/parasitologia , Variação Genética , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Plasmodium berghei/fisiologia , Plasmodium falciparum/fisiologia , RNA Mensageiro/genética , Análise de Sequência de RNA
13.
Nucleic Acids Res ; 40(22): 11684-96, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23042677

RESUMO

MicroRNAs (miRNAs) are 22-nt non-coding RNAs involved in the regulation of cellular gene expression and potential cellular defense against viral infection. Using in silico analyses, we predicted target sites for 22 human miRNAs in the HIV genome. Transfection experiments using synthetic miRNAs showed that five of these miRNAs capably decreased HIV replication. Using one of these five miRNAs, human miR-326 as an example, we demonstrated that the degree of complementarity between the predicted viral sequence and cellular miR-326 correlates, in a Dicer-dependent manner, with the potency of miRNA-mediated restriction of viral replication. Antagomirs to miR-326 that knocked down this cell endogenous miRNA increased HIV-1 replication in cells, suggesting that miR-326 is physiologically functional in moderating HIV-1 replication in human cells.


Assuntos
HIV-1/genética , MicroRNAs/metabolismo , Replicação Viral , Pareamento de Bases , Sequência de Bases , Linhagem Celular , Células Cultivadas , Simulação por Computador , Genoma Viral , HIV-1/fisiologia , Humanos , Células Jurkat , MicroRNAs/química , RNA Mensageiro/química , RNA Mensageiro/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-37987019

RESUMO

Africa faces both a disproportionate burden of infectious diseases coupled with unmet needs in bioinformatics and data science capabilities which impacts the ability of African biomedical researchers to vigorously pursue research and partner with institutions in other countries. The African Centers of Excellence in Bioinformatics and Data Intensive Science are collaborating with African academic institutions, industry partners, the Foundation for the National Institutes of Health (FNIH) and the National Institute of Allergy and Infectious Diseases (NIAID) at the National Institutes of Health (NIH) in a public-private partnership to address these challenges through enhancing computational infrastructure, fostering the development of advanced bioinformatics and data science skills among local researchers and students and providing innovative emerging technologies for infectious diseases research.

15.
Cell Host Microbe ; 30(7): 1020-1033.e6, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35568028

RESUMO

Antibiotics are a modifiable iatrogenic risk factor for the most common human nosocomial fungal infection, invasive candidiasis, yet the underlying mechanisms remain elusive. We found that antibiotics enhanced the susceptibility to murine invasive candidiasis due to impaired lymphocyte-dependent IL-17A- and GM-CSF-mediated antifungal immunity within the gut. This led to non-inflammatory bacterial escape and systemic bacterial co-infection, which could be ameliorated by IL-17A or GM-CSF immunotherapy. Vancomycin alone similarly enhanced the susceptibility to invasive fungal infection and systemic bacterial co-infection. Mechanistically, vancomycin reduced the frequency of gut Th17 cells associated with impaired proliferation and RORγt expression. Vancomycin's effects on Th17 cells were indirect, manifesting only in vivo in the presence of dysbiosis. In humans, antibiotics were associated with an increased risk of invasive candidiasis and death after invasive candidiasis. Our work highlights the importance of antibiotic stewardship in protecting vulnerable patients from life-threatening infections and provides mechanistic insights into a controllable iatrogenic risk factor for invasive candidiasis.


Assuntos
Antibacterianos , Candidíase Invasiva , Coinfecção , Animais , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Bactérias/efeitos dos fármacos , Bactérias/imunologia , Candida albicans/imunologia , Candidíase Invasiva/imunologia , Candidíase Invasiva/microbiologia , Coinfecção/imunologia , Coinfecção/microbiologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Humanos , Doença Iatrogênica , Imunoterapia , Interleucina-17/imunologia , Interleucina-17/uso terapêutico , Camundongos , Células Th17/metabolismo , Vancomicina/farmacologia
16.
BMC Genomics ; 12: 587, 2011 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22129310

RESUMO

BACKGROUND: It has been shown that nearly a quarter of the initial predicted gene models in the Plasmodium falciparum genome contain errors. Although there have been efforts to obtain complete cDNA sequences to correct the errors, the coverage of cDNA sequences on the predicted genes is still incomplete, and many gene models for those expressed in sexual or mosquito stages have not been validated. Antisense transcripts have widely been reported in P. falciparum; however, the extent and pattern of antisense transcripts in different developmental stages remain largely unknown. RESULTS: We have sequenced seven bidirectional libraries from ring, early and late trophozoite, schizont, gametocyte II, gametocyte V, and ookinete, and four strand-specific libraries from late trophozoite, schizont, gametocyte II, and gametocyte V of the 3D7 parasites. Alignment of the cDNA sequences to the 3D7 reference genome revealed stage-specific antisense transcripts and novel intron-exon splicing junctions. Sequencing of strand-specific cDNA libraries suggested that more genes are expressed in one direction in gametocyte than in schizont. Alternatively spliced genes, antisense transcripts, and stage-specific expressed genes were also characterized. CONCLUSIONS: It is necessary to continue to sequence cDNA from different developmental stages, particularly those of non-erythrocytic stages. The presence of antisense transcripts in some gametocyte and ookinete genes suggests that these antisense RNA may play an important role in gene expression regulation and parasite development. Future gene expression studies should make use of directional cDNA libraries. Antisense transcripts may partly explain the observed discrepancy between levels of mRNA and protein expression.


Assuntos
Expressão Gênica , Plasmodium falciparum/genética , RNA Antissenso/genética , RNA Mensageiro/genética , Processamento Alternativo , Animais , DNA Complementar , Éxons , Íntrons , Plasmodium falciparum/fisiologia
17.
Hum Mutat ; 31(9): 1080-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20652909

RESUMO

Hyper-IgM syndrome and Common Variable Immunodeficiency are heterogeneous disorders characterized by a predisposition to serious infection and impaired or absent neutralizing antibody responses. Although a number of single gene defects have been associated with these immune deficiency disorders, the genetic basis of many cases is not known. To facilitate mutation screening in patients with these syndromes, we have developed a custom 300-kb resequencing array, the Hyper-IgM/CVID chip, which interrogates 1,576 coding exons and intron-exon junction regions from 148 genes implicated in B-cell development and immunoglobulin isotype switching. Genomic DNAs extracted from patients were hybridized to the array using a high-throughput protocol for target sequence amplification, pooling, and hybridization. A Web-based application, SNP Explorer, was developed to directly analyze and visualize the single nucleotide polymorphism (SNP) annotation and for quality filtering. Several mutations in known disease-susceptibility genes such as CD40LG, TNFRSF13B, IKBKG, AICDA, as well as rare nucleotide changes in other genes such as TRAF3IP2, were identified in patient DNA samples and validated by direct sequencing. We conclude that the Hyper-IgM/CVID chip combined with SNP Explorer may provide a cost-effective tool for high-throughput discovery of novel mutations among hundreds of disease-relevant genes in patients with inherited antibody deficiency.


Assuntos
Síndromes de Imunodeficiência/diagnóstico , Síndromes de Imunodeficiência/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Polimorfismo de Nucleotídeo Único/genética , Análise de Sequência de DNA/métodos , Software , Frequência do Gene/genética , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala/economia , Humanos , Internet , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes
18.
BMC Med ; 8: 27, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20492690

RESUMO

BACKGROUND: Breast cancer studies frequently focus on the role of the tumor microenvironment in the promotion of cancer; however, the influence of the normal breast microenvironment on cancer cells remains relatively unknown. To investigate the role of the normal breast microenvironment on breast cancer cell tumorigenicity, we examined whether extracellular matrix molecules (ECM) derived from premenopausal African-American (AA) or Caucasian-American (CAU) breast tissue would affect the tumorigenicity of cancer cells in vitro and in vivo. We chose these two populations because of the well documented predisposition of AA women to develop aggressive, highly metastatic breast cancer compared to CAU women. METHODS: The effects of primary breast fibroblasts on tumorigenicity were analyzed via real-time PCR arrays and mouse xenograft models. Whole breast ECM was isolated, analyzed via zymography, and its effects on breast cancer cell aggressiveness were tested in vitro via soft agar and invasion assays, and in vivo via xenograft models. Breast ECM and hormone metabolites were analyzed via mass spectrometry. RESULTS: Mouse mammary glands humanized with premenopausal CAU fibroblasts and injected with primary breast cancer cells developed significantly larger tumors compared to AA humanized glands. Examination of 164 ECM molecules and cytokines from CAU-derived fibroblasts demonstrated a differentially regulated set of ECM proteins and increased cytokine expression. Whole breast ECM was isolated; invasion and soft agar assays demonstrated that estrogen receptor (ER)-, progesterone receptor (PR)/PR- cells were significantly more aggressive when in contact with AA ECM, as were ER+/PR+ cells with CAU ECM. Using zymography, protease activity was comparatively upregulated in CAU ECM. In xenograft models, CAU ECM significantly increased the tumorigenicity of ER+/PR+ cells and enhanced metastases. Mass spectrometry analysis of ECM proteins showed that only 1,759 of approximately 8,000 identified were in common. In the AA dataset, proteins associated with breast cancer were primarily related to tumorigenesis/neoplasia, while CAU unique proteins were involved with growth/metastasis. Using a novel mass spectrometry method, 17 biologically active hormones were measured; estradiol, estriol and 2-methoxyestrone were significantly higher in CAU breast tissue. CONCLUSIONS: This study details normal premenopausal breast tissue composition, delineates potential mechanisms for breast cancer development, and provides data for further investigation into the role of the microenvironment in cancer disparities.


Assuntos
Neoplasias da Mama/imunologia , Mama/imunologia , Mama/fisiologia , Matriz Extracelular/imunologia , Pré-Menopausa , Adulto , Negro ou Afro-Americano , Animais , Neoplasias da Mama/etnologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Matriz Extracelular/química , Feminino , Humanos , Espectrometria de Massas , Camundongos , Pessoa de Meia-Idade , Transplante Heterólogo , Estados Unidos , População Branca , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Open Forum Infect Dis ; 7(12): ofz367, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33324725

RESUMO

Background: Intestinal microbial dysbiosis is evident in chronic HIV-infected individuals and may underlie inflammation that persists even during antiretroviral therapy (ART). It remains unclear, however, how early after HIV infection gut dysbiosis emerges and how it is affected by early ART. Methods: Fecal microbiota were studied by 16s rDNA sequencing in 52 Thai men who have sex with men (MSM), at diagnosis of acute HIV infection (AHI), Fiebig Stages 1-5 (F1-5), and after 6 months of ART initiation, and in 7 Thai MSM HIV-uninfected controls. Dysbiotic bacterial taxa were associated with relevant inflammatory markers. Results: Fecal microbiota profiling of AHI pre-ART vs HIV-uninfected controls showed a mild dysbiosis. Transition from F1-3 of acute infection was characterized by enrichment in pro-inflammatory bacteria. Lower proportions of Bacteroidetes and higher frequencies of Proteobacteria and Fusobacteria members were observed post-ART compared with pre-ART. Fusobacteria members were positively correlated with levels of soluble CD14 in AHI post-ART. Conclusions: Evidence of gut dysbiosis was observed during early acute HIV infection and was partially restored upon early ART initiation. The association of dysbiotic bacterial taxa with inflammatory markers suggests that a potential relationship between altered gut microbiota and systemic inflammation may also be established during AHI.

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