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1.
Clin Infect Dis ; 76(3): e540-e543, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35686436

RESUMO

We enrolled arriving international air travelers in a severe acute respiratory syndrome coronavirus 2 genomic surveillance program. We used molecular testing of pooled nasal swabs and sequenced positive samples for sublineage. Traveler-based surveillance provided early-warning variant detection, reporting the first US Omicron BA.2 and BA.3 in North America.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Aeroportos , COVID-19/diagnóstico , Genômica
3.
Proc Natl Acad Sci U S A ; 111(13): 4928-33, 2014 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-24639495

RESUMO

The adaptive immune system confers protection by generating a diverse repertoire of antibody receptors that are rapidly expanded and contracted in response to specific targets. Next-generation DNA sequencing now provides the opportunity to survey this complex and vast repertoire. In the present work, we describe a set of tools for the analysis of antibody repertoires and their application to elucidating the dynamics of the response to viral vaccination in human volunteers. By analyzing data from 38 separate blood samples across 2 y, we found that the use of the germ-line library of V and J segments is conserved between individuals over time. Surprisingly, there appeared to be no correlation between the use level of a particular VJ combination and degree of expansion. We found the antibody RNA repertoire in each volunteer to be highly dynamic, with each individual displaying qualitatively different response dynamics. By using combinatorial phage display, we screened selected VH genes paired with their corresponding VL library for affinity against the vaccine antigens. Altogether, this work presents an additional set of tools for profiling the human antibody repertoire and demonstrates characterization of the fast repertoire dynamics through time in multiple individuals responding to an immune challenge.


Assuntos
Anticorpos/imunologia , Imunidade/imunologia , Vacinas Virais/imunologia , Células Clonais , Vetores Genéticos , Voluntários Saudáveis , Humanos , Região Variável de Imunoglobulina/genética , Masculino , Mutação/genética , Reprodutibilidade dos Testes , Fatores de Tempo , Recombinação V(D)J/genética , Vacinação
4.
PLoS Pathog ; 9(11): e1003754, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24278016

RESUMO

Broadly neutralizing HIV antibodies (bnAbs) are typically highly somatically mutated, raising doubts as to whether they can be elicited by vaccination. We used 454 sequencing and designed a novel phylogenetic method to model lineage evolution of the bnAbs PGT121-134 and found a positive correlation between the level of somatic hypermutation (SHM) and the development of neutralization breadth and potency. Strikingly, putative intermediates were characterized that show approximately half the mutation level of PGT121-134 but were still capable of neutralizing roughly 40-80% of PGT121-134 sensitive viruses in a 74-virus panel at median titers between 15- and 3-fold higher than PGT121-134. Such antibodies with lower levels of SHM may be more amenable to elicitation through vaccination while still providing noteworthy coverage. Binding characterization indicated a preference of inferred intermediates for native Env binding over monomeric gp120, suggesting that the PGT121-134 lineage may have been selected for binding to native Env at some point during maturation. Analysis of glycan-dependent neutralization for inferred intermediates identified additional adjacent glycans that comprise the epitope and suggests changes in glycan dependency or recognition over the course of affinity maturation for this lineage. Finally, patterns of neutralization of inferred bnAb intermediates suggest hypotheses as to how SHM may lead to potent and broad HIV neutralization and provide important clues for immunogen design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Anticorpos Neutralizantes/genética , Feminino , Anticorpos Anti-HIV/genética , Proteína gp120 do Envelope de HIV/genética , HIV-1/genética , Humanos , Masculino , Polissacarídeos/genética , Polissacarídeos/imunologia
5.
J Immunol ; 184(12): 6986-92, 2010 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20495067

RESUMO

Individual variation in the Ig germline gene repertoire leads to individual differences in the combinatorial diversity of the Ab repertoire, but the study of such variation has been problematic. The application of high-throughput DNA sequencing to the study of rearranged Ig genes now makes this possible. The sequencing of thousands of VDJ rearrangements from an individual, either from genomic DNA or expressed mRNA, should allow their germline IGHV, IGHD, and IGHJ repertoires to be inferred. In addition, where previously mere glimpses of diversity could be gained from sequencing studies, new large data sets should allow the rearrangement frequency of different genes and alleles to be seen with clarity. We analyzed the DNA of 108,210 human IgH chain rearrangements from 12 individuals and determined their individual IGH genotypes. The number of reportedly functional IGHV genes and allelic variants ranged from 45 to 60, principally because of variable levels of gene heterozygosity, and included 14 previously unreported IGHV polymorphisms. New polymorphisms of the IGHD3-16 and IGHJ6 genes were also seen. At heterozygous loci, remarkably different rearrangement frequencies were seen for the various IGHV alleles, and these frequencies were consistent between individuals. The specific alleles that make up an individual's Ig genotype may therefore be critical in shaping the combinatorial repertoire. The extent of genotypic variation between individuals is highlighted by an individual with aplastic anemia who appears to lack six contiguous IGHD genes on both chromosomes. These deletions significantly alter the potential expressed IGH repertoire, and possibly immune function, in this individual.


Assuntos
Genes de Cadeia Pesada de Imunoglobulina , Região Variável de Imunoglobulina/genética , Sequência de Bases , Rearranjo Gênico do Linfócito B , Genótipo , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético
6.
Genome Biol ; 23(1): 236, 2022 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348471

RESUMO

Effectively monitoring the spread of SARS-CoV-2 mutants is essential to efforts to counter the ongoing pandemic. Predicting lineage abundance from wastewater, however, is technically challenging. We show that by sequencing SARS-CoV-2 RNA in wastewater and applying algorithms initially used for transcriptome quantification, we can estimate lineage abundance in wastewater samples. We find high variability in signal among individual samples, but the overall trends match those observed from sequencing clinical samples. Thus, while clinical sequencing remains a more sensitive technique for population surveillance, wastewater sequencing can be used to monitor trends in mutant prevalence in situations where clinical sequencing is unavailable.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Águas Residuárias , RNA Viral/genética , Transcriptoma
7.
J Clin Microbiol ; 49(12): 4077-82, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21956987

RESUMO

Monitoring HIV drug resistance is an important component of the World Health Organization's global HIV program. HIV drug resistance testing is optimal with commercially available clinically validated test kits using plasma; however, that type of testing may not be feasible or affordable in resource-constrained settings. HIV genotyping from dried blood spots (DBS) with noncommercial (in-house) assays may facilitate the capture of HIV drug resistance outcomes in resource-constrained settings but has had varying rates of success. With in-house assays for HIV reverse transcriptase, we evaluated the yield of genotyping DBS samples collected from HIV-infected children who were enrolled in two clinical trials conducted in sub-Saharan Africa (median HIV viral load, 5.88 log(10) HIV RNA copies/ml; range, 4.04 to 6.99). Overall, HIV genotypes were obtained for 94 (89.5%) of 105 samples tested (95% and 84% from clinical trials #1 and #2, respectively); however, successful analysis of 15 (16.1%) of the 94 samples required repeat testing using a different set of primers on previously synthesized cDNA. The yield of genotyping was lower on the DBS that were stored suboptimally from clinical trial #2 (56% versus 88% for optimally stored). Concordance with plasma genotypes derived using a clinically validated, commercial kit-based assay (ViroSeq HIV-1 genotyping system) was also assessed in a subset of children with paired testing. For 34 samples with paired DBS and plasma genotypes, there was 100% concordance for major drug resistance mutations. DBS genotyping using in-house assays provides an alternative for antiretroviral drug resistance testing in children in resource-constrained regions but may require region-specific optimization before widespread use.


Assuntos
Sangue/virologia , Dessecação , Farmacorresistência Viral , Infecções por HIV/diagnóstico , Infecções por HIV/virologia , HIV-1/genética , Manejo de Espécimes/métodos , África Subsaariana , Antirretrovirais/farmacologia , Criança , Pré-Escolar , Países em Desenvolvimento , Genótipo , Transcriptase Reversa do HIV/genética , HIV-1/isolamento & purificação , Humanos , Lactente
8.
medRxiv ; 2021 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-34494031

RESUMO

Effectively monitoring the spread of SARS-CoV-2 variants is essential to efforts to counter the ongoing pandemic. Wastewater monitoring of SARS-CoV-2 RNA has proven an effective and efficient technique to approximate COVID-19 case rates in the population. Predicting variant abundances from wastewater, however, is technically challenging. Here we show that by sequencing SARS-CoV-2 RNA in wastewater and applying computational techniques initially used for RNA-Seq quantification, we can estimate the abundance of variants in wastewater samples. We show by sequencing samples from wastewater and clinical isolates in Connecticut U.S.A. between January and April 2021 that the temporal dynamics of variant strains broadly correspond. We further show that this technique can be used with other wastewater sequencing techniques by expanding to samples taken across the United States in a similar timeframe. We find high variability in signal among individual samples, and limited ability to detect the presence of variants with clinical frequencies <10%; nevertheless, the overall trends match what we observed from sequencing clinical samples. Thus, while clinical sequencing remains a more sensitive technique for population surveillance, wastewater sequencing can be used to monitor trends in variant prevalence in situations where clinical sequencing is unavailable or impractical.

9.
Immunogenetics ; 62(11-12): 773-80, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20882385

RESUMO

Major histocompatibility complex (MHC) class I alleles of nonhuman primates have been associated with disease susceptibility, resistance, and resolution. Here, using high-resolution pyrosequencing, we characterized MHC class I transcripts expressed in Mauritian cynomolgus macaques (MCM), a nonhuman primate population with restricted MHC diversity. Using this approach, we identified 67 distinct MHC class I transcripts encoded by the seven most frequent MCM MHC class I haplotypes, 40 (60%) of which span the complete open reading frames. These results double the number of MHC class I sequences previously defined by cloning and Sanger sequencing of cDNA-PCR products and provide a rapid, high-throughput, and economical method for MHC characterization. Overall, this approach significantly expanded our knowledge of MCM haplotypes and will facilitate future studies on disease pathogenesis and protective cellular immunity.


Assuntos
Genes MHC Classe I , Macaca fascicularis/genética , Macaca fascicularis/imunologia , Animais , Clonagem Molecular , Haplótipos , Análise de Sequência de DNA
10.
Mol Biol Cell ; 18(10): 3764-75, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17634284

RESUMO

Because only few of its client proteins are known, the physiological roles of the endoplasmic reticulum chaperone glucose-regulated protein 94 (GRP94) are poorly understood. Using targeted disruption of the murine GRP94 gene, we show that it has essential functions in embryonic development. grp94-/- embryos die on day 7 of gestation, fail to develop mesoderm, primitive streak, or proamniotic cavity. grp94-/- ES cells grow in culture and are capable of differentiation into cells representing all three germ layers. However, these cells do not differentiate into cardiac, smooth, or skeletal muscle. Differentiation cultures of mutant ES cells are deficient in secretion of insulin-like growth factor II and their defect can be complemented with exogenous insulin-like growth factors I or II. The data identify insulin-like growth factor II as one developmentally important protein whose production depends on the activity of GRP94.


Assuntos
Fator de Crescimento Insulin-Like II/metabolismo , Glicoproteínas de Membrana/metabolismo , Mesoderma/metabolismo , Desenvolvimento Muscular/fisiologia , Animais , Animais Recém-Nascidos , Biomarcadores/metabolismo , Diferenciação Celular , Células Cultivadas , Perda do Embrião , Desenvolvimento Embrionário , Células-Tronco Embrionárias/citologia , Estruturas Embrionárias/citologia , Gástrula/citologia , Deleção de Genes , Marcação de Genes , Heterozigoto , Homozigoto , Fator de Crescimento Insulin-Like II/deficiência , Glicoproteínas de Membrana/genética , Camundongos , Fenótipo
11.
J Mol Diagn ; 21(3): 369-374, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30605766

RESUMO

Comprehensive next-generation sequencing (NGS) tests are increasingly used as first-line tests in the evaluation of patients with suspected heritable disease. Despite major technical simplifications, these assays still pose significant challenges for molecular testing laboratories. Existing professional guidelines and recommendations provide a framework for laboratories implementing such tests, but in-depth, concrete guidance is generally not provided. Consequently, there is variability in how laboratories interpret and subsequently implement these regulatory frameworks. To address the need for more detailed guidance, the College of American Pathologists with representation from the Association for Molecular Pathologists assembled a working group to create a practical resource for clinical laboratories. This initial work is focused on variant detection in the setting of inherited disease and provides structured worksheets that guide the user through the entire life cycle of an NGS test, including design, optimization, validation, and quality management with additional guidance for clinical bioinformatics. This resource is designed to be a living document that is publicly available and will be updated with user and expert feedback as the wet bench and bioinformatic landscapes continue to evolve. It is intended to facilitate the standardization of NGS testing across laboratories and therefore to improve patient care.


Assuntos
Serviços de Laboratório Clínico , Doenças Genéticas Inatas/diagnóstico , Guias como Assunto , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Projetos de Pesquisa , Biologia Computacional , Humanos
12.
J Neurosci ; 27(48): 13329-40, 2007 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-18045927

RESUMO

Investigations of the molecular mechanisms underlying major depressive disorder (MDD) have been hampered by the complexity of brain tissue and sensitivity of gene expression profiling approaches. To address these issues, we used discrete microdissections of postmortem dorsolateral prefrontal cortex (DLPFC) (area 9) and an oligonucleotide (60mer) microarray hybridization procedure that increases sensitivity without RNA amplification. Mixed-effects statistical methods were used to rigorously control for medication usage in the subset of medicated depressed subjects. These analyses yielded a rich profile of dysregulated genes. Two of the most highly dysregulated genes of interest were stresscopin, a neuropeptide involved in stress responses, and Forkhead box D3 (FOXD3), a transcription factor. Secondary cell-based analysis demonstrated that stresscopin and FoxD3 are increased in neurons of DLPFC gray matter of MDD subjects. These findings identify abnormal gene expression in a discrete region of MDD subjects and contribute to further elucidation of the molecular alterations of this complex mood disorder.


Assuntos
Transtorno Depressivo Maior/patologia , Perfilação da Expressão Gênica/métodos , Expressão Gênica/fisiologia , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Ciclo Celular/genética , Morte Celular , Diferenciação Celular/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Humanos , Hibridização In Situ/métodos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Mudanças Depois da Morte , Transdução de Sinais/genética , Fatores de Transcrição
13.
Biol Psychiatry ; 59(9): 775-85, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16458261

RESUMO

BACKGROUND: Increased serum levels of TNFalpha and other pro-inflammatory cytokines have been found in patients with major depression and several other psychiatric conditions. In rodents, these cytokines produce symptoms commonly referred to as "sickness behavior." Some of these, including reduced feeding and decreased social and exploratory behavior, are reminiscent of those seen in depressed patients. Interpretation of these effects is complicated by the malaise caused by acute injections of pro-inflammatory cytokines, however. Thus, it is unclear whether cytokines are involved in the etiology of depressive symptoms. METHODS: We used a panel of behavioral assays to assess TNFR1(-/-) and TNFR2(-/-) mice for anxiety and depression-like behaviors. RESULTS: We show that deletion of either TNFR1 or TNFR2 leads to an antidepressant-like response in the forced swim test and that mice lacking TNFR2 demonstrate a hedonic response in a sucrose drinking test compared with wildtype littermates. In addition, deletion of TNFR1 leads to decreased fear conditioning. There were no differences in behavior in anxiety tests for either null mutant. CONCLUSIONS: These results are consistent with the hypothesis that TNFalpha can induce depression-like symptoms even in the absence of malaise and demonstrate that both receptor subtypes can be involved in this response.


Assuntos
Ansiedade/fisiopatologia , Depressão/fisiopatologia , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/fisiologia , Análise de Variância , Animais , Comportamento Animal/fisiologia , Condicionamento Psicológico , Modelos Animais de Doenças , Comportamento de Ingestão de Líquido/fisiologia , Comportamento Exploratório/fisiologia , Medo , Expressão Gênica/fisiologia , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/fisiologia , RNA Mensageiro/metabolismo , Tempo de Reação/fisiologia , Receptores do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral , Receptores Tipo II do Fator de Necrose Tumoral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sacarose , Natação/fisiologia , Receptores Chamariz do Fator de Necrose Tumoral
14.
PLoS One ; 11(1): e0146687, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26756901

RESUMO

BACKGROUND: Ultra deep sequencing is of increasing use not only in research but also in diagnostics. For implementation of ultra deep sequencing assays in clinical laboratories for routine diagnostics, intra- and inter-laboratory testing are of the utmost importance. METHODS: A multicenter study was conducted to validate an updated assay design for 454 Life Sciences' GS FLX Titanium system targeting protease/reverse transcriptase (RTP) and env (V3) regions to identify HIV-1 drug-resistance mutations and determine co-receptor use with high sensitivity. The study included 30 HIV-1 subtype B and 6 subtype non-B samples with viral titers (VT) of 3,940-447,400 copies/mL, two dilution series (52,129-1,340 and 25,130-734 copies/mL), and triplicate samples. Amplicons spanning PR codons 10-99, RT codons 1-251 and the entire V3 region were generated using barcoded primers. Analysis was performed using the GS Amplicon Variant Analyzer and geno2pheno for tropism. For comparison, population sequencing was performed using the ViroSeq HIV-1 genotyping system. RESULTS: The median sequencing depth across the 11 sites was 1,829 reads per position for RTP (IQR 592-3,488) and 2,410 for V3 (IQR 786-3,695). 10 preselected drug resistant variants were measured across sites and showed high inter-laboratory correlation across all sites with data (P<0.001). The triplicate samples of a plasmid mixture confirmed the high inter-laboratory consistency (mean% ± stdev: 4.6 ±0.5, 4.8 ±0.4, 4.9 ±0.3) and revealed good intra-laboratory consistency (mean% range ± stdev range: 4.2-5.2 ± 0.04-0.65). In the two dilutions series, no variants >20% were missed, variants 2-10% were detected at most sites (even at low VT), and variants 1-2% were detected by some sites. All mutations detected by population sequencing were also detected by UDS. CONCLUSIONS: This assay design results in an accurate and reproducible approach to analyze HIV-1 mutant spectra, even at variant frequencies well below those routinely detectable by population sequencing.


Assuntos
Comportamento Cooperativo , Farmacorresistência Viral/genética , HIV-1/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Tropismo/genética , Aminoácidos/genética , Seguimentos , Humanos , Mutação/genética , Plasmídeos/genética , Reprodutibilidade dos Testes
15.
Arch Pathol Lab Med ; 139(4): 508-17, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25356985

RESUMO

CONTEXT: Next-generation sequencing allows for high-throughput processing and sensitive variant detection in multiple genes from small samples. For many diseases, including cancer, a comprehensive mutational profile of a targeted list of genes can be used to simultaneously inform patient care, establish eligibility for ongoing clinical trials, and further research. OBJECTIVE: To validate a pan-cancer, next-generation-sequencing assay for use in the clinical laboratory. DESIGN: DNA was extracted from 68 clinical specimens (formalin-fixed, paraffin-embedded; fine-needle aspirates; peripheral blood; or bone marrow) and 5 normal controls. Sixty-four DNA samples (94%; 64 of 68) were successfully processed with the TruSeq Amplicon Cancer Panel (Illumina Inc, San Diego, California) and sequenced in 4 sequencing runs. The data were analyzed at 4 different filter settings for sequencing coverage and variant frequency cutoff. RESULTS: Libraries created from 40 specimens could be successfully sequenced in a single run and still yield sufficient coverage for robust data analysis of individual samples. Sensitivity for mutation detection down to 5% was demonstrated using dilutions of clinical specimens and control samples. The test was highly repeatable and reproducible and showed 100% concordance with clinically validated Sanger sequencing results. Comparison to an alternate next-generation sequencing technology was performed by also processing 9 of the specimens with the AmpliSeq Cancer Hotspot Panel (version 2; Life Technologies, Grand Island, New York). Thirty of the 31 (97%) TruSeq-detected variants covered by the designs of both panels were confirmed. CONCLUSIONS: A sensitive, high-throughput, pan-cancer mutation panel for sequencing of cancer hot-spot mutations in 42 genes was validated for routine use in clinical testing.


Assuntos
Técnicas de Laboratório Clínico/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Mutação , Neoplasias/genética , DNA de Neoplasias/química , DNA de Neoplasias/genética , DNA de Neoplasias/isolamento & purificação , Predisposição Genética para Doença/genética , Testes Genéticos/métodos , Humanos , Neoplasias/diagnóstico , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes
16.
J Virus Erad ; 1(4): 264-268, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26855971

RESUMO

BACKGROUND: Limited data exist comparing viral quasispecies between cerebrospinal fluid (CSF) and plasma compartments during primary HIV infection. Deep sequencing is a new method to examine the HIV plasma and CSF quasispecies. METHODS: In this pilot study, deep sequencing of protease (PR) and reverse transcriptase (RT) was performed in plasma and CSF from participants during primary HIV infection. Estimated mutational load was calculated by mutant variant frequency multiplied by HIV-RNA level. RESULTS: Paired plasma and CSF samples were studied from five antiretroviral therapy-naïve male participants with median 109 days post estimated transmission, age 32 years, CD4 cell count 580 cells/µL, HIV-RNA 5.18 log10 copies/mL in plasma and 3.67 log10 copies/mL in CSF. Plasma samples averaged 7,124 reads of PR and 2,448 reads of RT, whereas CSF samples averaged 7,082 and 2,792 reads, respectively. A distinct drug-resistance pattern with linked mutations present at significant levels (5-10%) was detected in one participant in CSF. Other low abundance variants (>0.2%) were detected in plasma and CSF of four out of five participants. CONCLUSIONS: Deep sequencing of CSF HIV is technically possible with sufficient HIV-RNA levels. Differences between the quasispecies in the two compartments detected in one participant, which were present with a high mutational load in CSF at an estimated 3.6 months after HIV infection, suggest that early CNS compartmentalisation may be revealed by sensitive deep-sequencing methods. The presence of distinct low abundance (<1%) resistance variants in plasma and CSF of three other subjects may be significant, but further investigation is needed.

17.
Viruses ; 6(9): 3428-37, 2014 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-25256391

RESUMO

Low-frequency HIV variants possessing resistance mutations against non­nucleoside reverse transcriptase inhibitors (NNRTI), especially at HIV reverse transcriptase (RT) amino acid (aa) positions K103 and Y181, have been shown to adversely affect treatment response. Therapeutic failure correlates with both the mutant viral variant frequency and the mutational load. We determined the prevalence of NNRTI resistance mutations at several RT aa positions in viruses from 204 antiretroviral (ARV)-naïve HIV-infected individuals using deep sequencing, and examined the relationship between mutant variant frequency and mutational load for those variants. Deep sequencing to ≥0.4% levels found variants with major NNRTI-resistance mutations having a Stanford-HIVdb algorithm value ≥30 for efavirenz and/or nevirapine in 52/204 (25.5%) ARV-naïve HIV-infected persons. Eighteen different major NNRTI mutations were identified at 11 different positions, with the majority of variants being at frequency >1%. The frequency of these variants correlated strongly with the mutational load, but this correlation weakened at low frequencies. Deep sequencing detected additional major NNRTI-resistant viral variants in treatment-naïve HIV-infected individuals. Our study suggests the significance of screening for mutations at all RT aa positions (in addition to K103 and Y181) to estimate the true burden of pre-treatment NNRTI-resistance. An important finding was that variants at low frequency had a wide range of mutational loads (>100-fold) suggesting that frequency alone may underestimate the impact of specific NNRTI-resistant variants. We recommend further evaluation of all low-frequency NNRTI-drug resistant variants with special attention given to the impact of mutational loads of these variants on treatment outcomes.


Assuntos
Fármacos Anti-HIV/farmacologia , Farmacorresistência Viral/genética , Infecções por HIV/virologia , HIV-1/genética , Mutação , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Taxa de Mutação , Inibidores da Transcriptase Reversa/uso terapêutico
18.
J Virol Methods ; 204: 31-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24731928

RESUMO

The detection of mutant spectra within the viral quasispecies is critical for therapeutic management of HIV-1 infections. Routine clinical application of ultrasensitive genotyping requires reproducibility and concordance within and between laboratories. The goal of the study was to evaluate a new protocol on HIV-1 drug resistance testing by 454 ultra-deep pyrosequencing (454-UDS) in an international multicenter study. Sixteen blinded HIV-1 subtype B samples were provided for 454-UDS as both RNA and cDNA with viral titers of 88,600-573,000 HIV-1 RNA copies/ml. Eight overlapping amplicons spanning protease (PR) codons 10-99 and reverse transcriptase (RT) codons 1-251 were generated using molecular barcoded primers. 454-UDS was performed using the 454 Life Sciences/Roche GS FLX platform. PR and RT sequences were analyzed using 454 Life Sciences Amplicon Variant Analyzer (AVA) software. Quantified variation data were analyzed for intra-laboratory reproducibility and inter-laboratory concordance. Routine population sequencing was performed using the ViroSeq HIV-1 genotyping system. Eleven laboratories and the reference laboratory 454 Life Sciences sequenced the HIV-1 sample set. Data presented are derived from seven laboratories and the reference laboratory since severe study protocol execution errors occurred in four laboratories leading to exclusion. The median sequencing depth across all sites was 1364 reads per position (IQR=809-2065). 100% of the ViroSeq-reported mutations were also detected by 454-UDS. Minority HIV-1 drug resistance mutations, defined as HIV-1 drug resistance mutations identified at frequencies of 1-25%, were only detected by 454-UDS. Analysis of 10 preselected majority and minority mutations were consistently found across sites. The analysis of drug-resistance mutations detected between 1 and 10% demonstrated high intra- and inter-laboratory consistency in frequency estimates for both RNA and prepared cDNA samples, indicating robustness of the method. HIV-1 drug resistance testing using 454 ultra-deep pyrosequencing results in an accurate and highly reproducible, albeit complex, approach to the analysis of HIV-1 mutant spectra, even at frequencies well below those detected by routine population sequencing.


Assuntos
Farmacorresistência Viral , Técnicas de Genotipagem/métodos , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Cooperação Internacional , Biologia Computacional/métodos , HIV-1/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana/métodos , Software
19.
Cell Host Microbe ; 16(1): 105-14, 2014 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-24981332

RESUMO

B cells produce a diverse antibody repertoire by undergoing gene rearrangements. Pathogen exposure induces the clonal expansion of B cells expressing antibodies that can bind the infectious agent. To assess human B cell responses to trivalent seasonal influenza and monovalent pandemic H1N1 vaccination, we sequenced gene rearrangements encoding the immunoglobulin heavy chain, a major determinant of epitope recognition. The magnitude of B cell clonal expansions correlates with an individual's secreted antibody response to the vaccine, and the expanded clones are enriched with those expressing influenza-specific monoclonal antibodies. Additionally, B cell responses to pandemic influenza H1N1 vaccination and infection in different people show a prominent family of convergent antibody heavy chain gene rearrangements specific to influenza antigens. These results indicate that microbes can induce specific signatures of immunoglobulin gene rearrangements and that pathogen exposure can potentially be assessed from B cell repertoires.


Assuntos
Anticorpos Antivirais/genética , Anticorpos Antivirais/imunologia , Rearranjo Gênico do Linfócito B , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Formação de Anticorpos , Humanos , Vacinas contra Influenza/administração & dosagem
20.
Diabetes ; 62(7): 2618-22, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23462545

RESUMO

The primary associations of the HLA class II genes, HLA-DRB1 and HLA-DQB1, and the class I genes, HLA-A and HLA-B, with type 1 diabetes (T1D) are well established. However, the role of polymorphism at the HLA-DRB3, HLA-DRB4, and HLA-DRB5 loci remains unclear. In two separate studies, one of 500 subjects and 500 control subjects and one of 366 DRB1*03:01-positive samples from selected multiplex T1D families, we used Roche 454 sequencing with Conexio Genomics ASSIGN ATF 454 HLA genotyping software analysis to analyze sequence variation at these three HLA-DRB loci. Association analyses were performed on the two HLA-DRB loci haplotypes (DRB1-DRB3, -DRB4, or -DRB5). Three common HLA-DRB3 alleles (*01:01, *02:02, *03:01) were observed. DRB1*03:01 haplotypes carrying DRB3*02:02 conferred a higher T1D risk than did DRB1*03:01 haplotypes carrying DRB3*01:01 in DRB1*03:01/*03:01 homozygotes with two DRB3*01:01 alleles (odds ratio [OR] 3.4 [95% CI 1.46-8.09]), compared with those carrying one or two DRB3*02:02 alleles (OR 25.5 [3.43-189.2]) (P = 0.033). For DRB1*03:01/*04:01 heterozygotes, however, the HLA-DRB3 allele did not significantly modify the T1D risk of the DRB1*03:01 haplotype (OR 7.7 for *02:02; 6.8 for *01:01). These observations were confirmed by sequence analysis of HLA-DRB3 exon 2 in a targeted replication study of 281 informative T1D family members and 86 affected family-based association control (AFBAC) haplotypes. The frequency of DRB3*02:02 was 42.9% in the DRB1*03:01/*03:01 patients and 27.6% in the DRB1*03:01/*04 (P = 0.005) compared with 22.6% in AFBAC DRB1*03:01 chromosomes (P = 0.001). Analysis of T1D-associated alleles at other HLA loci (HLA-A, HLA-B, and HLA-DPB1) on DRB1*03:01 haplotypes suggests that DRB3*02:02 on the DRB1*03:01 haplotype can contribute to T1D risk.


Assuntos
Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Cadeias HLA-DRB3/genética , Polimorfismo Genético , Adulto , Alelos , Diabetes Mellitus Tipo 1/imunologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Haplótipos , Humanos , Masculino
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