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1.
Emerg Infect Dis ; 27(6): 1-9, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34013862

RESUMO

Human respiratory syncytial virus (HRSV) is the leading viral cause of serious pediatric respiratory disease, and lifelong reinfections are common. Its 2 major subgroups, A and B, exhibit some antigenic variability, enabling HRSV to circulate annually. Globally, research has increased the number of HRSV genomic sequences available. To ensure accurate molecular epidemiology analyses, we propose a uniform nomenclature for HRSV-positive samples and isolates, and HRSV sequences, namely: HRSV/subgroup identifier/geographic identifier/unique sequence identifier/year of sampling. We also propose a template for submitting associated metadata. Universal nomenclature would help researchers retrieve and analyze sequence data to better understand the evolution of this virus.


Assuntos
Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Criança , Variação Genética , Genótipo , Humanos , Epidemiologia Molecular , Filogenia , Vírus Sincicial Respiratório Humano/genética
2.
Bioinformatics ; 34(15): 2682-2683, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-30052913

RESUMO

Motivation: Genetic reporter assays are a convenient, relatively inexpensive method for studying the regulation of gene expression. Massively Parallel Reporter Assays (MPRA) are high-throughput functionalization assays that interrogate the transcriptional activity of many genetic variants at once using a library of synthetic barcoded constructs. Despite growing interest in this area, there are few computational tools to design and execute MPRA studies. Results: We designed an online web-tool and R package that allows for interactive MPRA experimental design encompassing both power analysis and design of constructs. Our tool is tuned using data from real MPRA studies. Users can adjust experimental parameters to examine the predicted effect on assay power as well as upload VCFs for automated construct sequence generation. Availability and implementation: The MPRA Design Tools web application is available here: https://andrewghazi.shinyapps.io/designmpra/, https://github.com/andrewGhazi/designMPRA and https://github.com/andrewGhazi/mpradesigntools. Supplementary information: Supplementary data are available at Bioinformatics online.


Assuntos
Biologia Computacional/métodos , Regulação da Expressão Gênica , Genes Reporter , Técnicas Genéticas , Software , Bioensaio/métodos
3.
Eur Respir J ; 48(5): 1329-1339, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27799386

RESUMO

Little is known about the relationship between the specific airway microbiota composition and severity of bronchiolitis. We aimed to identify nasopharyngeal microbiota profiles and link these profiles to acute severity in infants hospitalised for bronchiolitis.We conducted a multicentre prospective cohort study of 1005 infants (age <1 year) hospitalised for bronchiolitis over three winters, 2011-2014. By applying a 16S rRNA gene sequence and clustering approach to the nasopharyngeal aspirates collected within 24 h of hospitalisation, we determined nasopharyngeal microbiota profiles and their association with bronchiolitis severity. The primary outcome was intensive care use, i.e. admission to an intensive care unit or use of mechanical ventilation.We identified four nasopharyngeal microbiota profiles: three profiles were dominated by one of Haemophilus, Moraxella or Streptococcus, while the fourth profile had the highest bacterial richness. The rate of intensive care use was highest in infants with a Haemophilus-dominant profile and lowest in those with a Moraxella-dominant profile (20.2% versus 12.3%; unadjusted OR 1.81, 95% CI 1.07-3.11, p=0.03). After adjusting for 11 patient-level confounders, the rate remained significantly higher in infants with Haemophilus-dominant profiles (OR 1.98, 95% CI 1.08-3.62, p=0.03). These findings were externally validated in a separate cohort of 307 children hospitalised for bronchiolitis.


Assuntos
Bronquiolite/microbiologia , Microbiota , Nasofaringe/microbiologia , Cuidados Críticos , Feminino , Haemophilus , Hospitalização , Humanos , Lactente , Recém-Nascido , Tempo de Internação , Masculino , Moraxella , Razão de Chances , Prevotella , Estudos Prospectivos , RNA Ribossômico 16S/genética , Índice de Gravidade de Doença , Staphylococcus , Streptococcus , Resultado do Tratamento , Estados Unidos
4.
Prenat Diagn ; 36(11): 1009-1019, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27616633

RESUMO

OBJECTIVE: The goal was to develop methods for detection of chromosomal and subchromosomal abnormalities in fetal cells in the mother's circulation at 10-16 weeks' gestation using analysis by array comparative genomic hybridization (CGH) and/or next-generation sequencing (NGS). METHOD: Nucleated cells from 30 mL of blood collected at 10-16 weeks' gestation were separated from red cells by density fractionation and then immunostained to identify cytokeratin positive and CD45 negative trophoblasts. Individual cells were picked and subjected to whole genome amplification, genotyping, and analysis by array CGH and NGS. RESULTS: Fetal cells were recovered from most samples as documented by Y chromosome PCR, short tandem repeat analysis, array CGH, and NGS including over 30 normal male cells, one 47,XXY cell from an affected fetus, one trisomy 18 cell from an affected fetus, nine cells from a trisomy 21 case, three normal cells and one trisomy 13 cell from a case with confined placental mosaicism, and two chromosome 15 deletion cells from a case known by CVS to have a 2.7 Mb de novo deletion. CONCLUSION: We believe that this is the first report of using array CGH and NGS whole genome sequencing to detect chromosomal abnormalities in fetal trophoblastic cells from maternal blood. © 2016 The Authors. Prenatal Diagnosis published by John Wiley & Sons, Ltd.


Assuntos
Aberrações Cromossômicas , Hibridização Genômica Comparativa , Testes para Triagem do Soro Materno/métodos , Análise de Sequência de DNA , Trofoblastos/citologia , Variações do Número de Cópias de DNA , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Gravidez
6.
Viruses ; 13(6)2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073490

RESUMO

Respiratory syncytial virus (RSV) is an important cause of lower respiratory tract infection in infants, the elderly, and immunocompromised patients. RSV antibodies play a role in preventing reinfection and in clearance of RSV, but data regarding the levels of viral protein-specific antibodies elicited and their contribution to patient recovery from RSV-induced disease are limited. We prospectively enrolled a cohort of RSV-infected adult hematopoietic cell transplant (HCT) recipients (n = 40). Serum and nasal-wash samples were obtained at enrollment (acute samples) and convalescence (convalescent samples). We measured (1) humoral IgG and mucosal IgA binding antibody levels to multiple RSV proteins (F, G, N, P, and M2-1) by Western blot (WB); (2) neutralizing antibody (Nt Ab) titers by microneutralization assay; and (3) palivizumab-like antibody (PLA) concentrations by an ELISA-based competitive binding assay developed in the lab. Finally, we tested for correlations between protein-specific antibody levels and duration of viral shedding (normal: cleared in <14 days and delayed: cleared ≥14 days), as well as RSV/A and RSV/B subtypes. Convalescent sera from HCT recipients had significantly higher levels of anti-RSV antibodies to all 5 RSV structural proteins assayed (G, F, N, P, M2-1), higher Nt Abs to both RSV subtypes, and higher serum PLAs than at enrollment. Significantly higher levels of mucosal antibodies to 3 RSV structural proteins (G, N, and M2-1) were observed in the convalescent nasal wash versus acute nasal wash. Normal viral clearance group had significantly higher levels of serum IgG antibodies to F, N, and P viral proteins, higher Nt Ab to both RSV subtypes, and higher PLA, as well as higher levels of mucosal IgA antibodies to G and M2-1 viral proteins, and higher Nt Ab to both RSV subtypes compared to delayed viral clearance group. Normal RSV clearance was associated with higher IgG serum antibody levels to F and P viral proteins, and PLAs in convalescent serum (p < 0.05). Finally, overall antibody levels in RSV/A- and/B-infected HCT recipients were not significantly different. In summary, specific humoral and mucosal RSV antibodies are associated with viral clearance in HCT recipients naturally infected with RSV. In contrast to the humoral response, the F surface glycoprotein was not a major target of mucosal immunity. Our findings have implications for antigen selection in the development of RSV vaccines.


Assuntos
Anticorpos Antivirais/sangue , Imunidade Humoral/imunologia , Imunidade nas Mucosas/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Transplantados/estatística & dados numéricos , Proteínas Estruturais Virais/imunologia , Adulto , Anticorpos Neutralizantes/sangue , Formação de Anticorpos , Transplante de Células-Tronco Hematopoéticas , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue
7.
Nat Commun ; 9(1): 4720, 2018 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-30420638

RESUMO

This Article contains an error in Figure 2. In panel a, the second lane of the western blot should have been labelled 'siNT'. A correct version of Figure 2a appears in the Author Correction associated with this Article; the error has not been fixed in the original Article.

8.
Microbiome ; 6(1): 2, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29298732

RESUMO

BACKGROUND: The airway microbiome is a subject of great interest for the study of respiratory disease. Anterior nare samples are more accessible than samples from deeper within the nasopharynx. However, the correlation between the microbiota found in the anterior nares and the microbiota found within the nasopharynx is unknown. We assessed the anterior nares and nasopharyngeal microbiota to determine (1) the relation of the microbiota from these two upper airway sites and (2) if associations were maintained between the microbiota from these two sites and two bronchiolitis severity outcomes. RESULTS: Among 815 infants hospitalized at 17 US centers for bronchiolitis with optimal 16S rRNA gene sequence reads from both nasal swab and nasopharyngeal aspirate samples, there were strong intra-individual correlations in the microbial communities between the two sample types, especially relating to Haemophilus and Moraxella genera. By contrast, we found a high abundance of Staphylococcus genus in the nasal swabs-a pattern not found in the nasopharyngeal samples and not informative when predicting the dominant nasopharyngeal genera. While these disparities may have been due to sample processing differences (i.e., nasal swabs were mailed at ambient temperature to emulate processing of future parent collected swabs while nasopharyngeal aspirates were mailed on dry ice), a previously reported association between Haemophilus-dominant nasopharyngeal microbiota and the increased severity of bronchiolitis was replicated utilizing the nasal swab microbiota and the same outcome measures: intensive care use (adjusted OR 6.43; 95% CI 2.25-20.51; P < 0.001) and hospital length-of-stay (adjusted OR 4.31; 95% CI, 1.73-11.11; P = 0.002). Additionally, Moraxella-dominant nasopharyngeal microbiota was previously identified as protective against intensive care use, a result that was replicated when analyzing the nasal swab microbiota (adjusted OR 0.30; 95% CI, 0.11-0.64; P = 0.01). CONCLUSIONS: While the microbiota of the anterior nares and the nasopharynx are distinct, there is considerable overlap between the bacterial community compositions from these two anatomic sites. Despite processing differences between the samples, these results indicate that microbiota severity associations from the nasopharynx are recapitulated in the anterior nares, suggesting that nasal swab samples not only are effective sample types, but also can be used to detect microbial risk markers.


Assuntos
Bronquiolite/microbiologia , Cavidade Nasal/microbiologia , Nasofaringe/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA/métodos , Staphylococcus/isolamento & purificação , DNA Bacteriano/genética , DNA Ribossômico/genética , Feminino , Hospitalização , Humanos , Lactente , Estudos Longitudinais , Masculino , Microbiota , Staphylococcus/classificação , Staphylococcus/genética
9.
Nat Med ; 24(4): 505-511, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29578538

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer diagnosed in more than 200,000 women each year and is recalcitrant to targeted therapies. Although TNBCs harbor multiple hyperactive receptor tyrosine kinases (RTKs), RTK inhibitors have been largely ineffective in TNBC patients thus far. We developed a broadly effective therapeutic strategy for TNBC that is based on combined inhibition of receptors that share the negative regulator PTPN12. Previously, we and others identified the tyrosine phosphatase PTPN12 as a tumor suppressor that is frequently inactivated in TNBC. PTPN12 restrains several RTKs, suggesting that PTPN12 deficiency leads to aberrant activation of multiple RTKs and a co-dependency on these receptors. This in turn leads to the therapeutic hypothesis that PTPN12-deficient TNBCs may be responsive to combined RTK inhibition. However, the repertoire of RTKs that are restrained by PTPN12 in human cells has not been systematically explored. By methodically identifying the suite of RTK substrates (MET, PDGFRß, EGFR, and others) inhibited by PTPN12, we rationalized a combination RTK-inhibitor therapy that induced potent tumor regression across heterogeneous models of TNBC. Orthogonal approaches revealed that PTPN12 was recruited to and inhibited these receptors after ligand stimulation, thereby serving as a feedback mechanism to limit receptor signaling. Cancer-associated mutation of PTPN12 or reduced PTPN12 protein levels diminished this feedback mechanism, leading to aberrant activity of these receptors. Restoring PTPN12 protein levels restrained signaling from RTKs, including PDGFRß and MET, and impaired TNBC survival. In contrast with single agents, combined inhibitors targeting the PDGFRß and MET receptors induced the apoptosis in TNBC cells in vitro and in vivo. This therapeutic strategy resulted in tumor regressions in chemo-refractory patient-derived TNBC models. Notably, response correlated with PTPN12 deficiency, suggesting that impaired receptor feedback may establish a combined addiction to these proto-oncogenic receptors. Taken together, our data provide a rationale for combining RTK inhibitors in TNBC and other malignancies that lack receptor-activating mutations.


Assuntos
Proteína Tirosina Fosfatase não Receptora Tipo 12/metabolismo , Receptores de Superfície Celular/antagonistas & inibidores , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , Crizotinibe/farmacologia , Crizotinibe/uso terapêutico , Feminino , Humanos , Camundongos Nus , Mutação/genética , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 12/genética , Receptores Proteína Tirosina Quinases/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Sunitinibe/farmacologia , Sunitinibe/uso terapêutico , Neoplasias de Mama Triplo Negativas/enzimologia , Neoplasias de Mama Triplo Negativas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
PLoS One ; 12(4): e0175792, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28414749

RESUMO

BACKGROUND: The fusion (F) protein of RSV is the major vaccine target. This protein undergoes a conformational change from pre-fusion to post-fusion. Both conformations share antigenic sites II and IV. Pre-fusion F has unique antigenic sites p27, ø, α2α3ß3ß4, and MPE8; whereas, post-fusion F has unique antigenic site I. Our objective was to determine the antigenic variability for RSV/A and RSV/B isolates from contemporary and historical genotypes compared to a historical RSV/A strain. METHODS: The F sequences of isolates from GenBank, Houston, and Chile (N = 1,090) were used for this analysis. Sequences were compared pair-wise to a reference sequence, a historical RSV/A Long strain. Variability (calculated as %) was defined as changes at each amino acid (aa) position when compared to the reference sequence. Only aa at antigenic sites with variability ≥5% were reported. RESULTS: A total of 1,090 sequences (822 RSV/A and 268 RSV/B) were analyzed. When compared to the reference F, those domains with the greatest number of non-synonymous changes included the signal peptide, p27, heptad repeat domain 2, antigenic site ø, and the transmembrane domain. RSV/A subgroup had 7 aa changes in the antigenic sites: site I (N = 1), II (N = 1), p27 (N = 4), α2α3ß3ß4(AM14) (N = 1), ranging in frequency from 7-91%. In comparison, RSV/B had 19 aa changes in antigenic sites: I (N = 3), II (N = 1), p27 (N = 9), ø (N = 4), α2α3ß3ß4(AM14) (N = 1), and MPE8 (N = 1), ranging in frequency from 79-100%. DISCUSSION: Although antigenic sites of RSV F are generally well conserved, differences are observed when comparing the two subgroups to the reference RSV/A Long strain. Further, these discrepancies are accented in the antigenic sites in pre-fusion F of RSV/B isolates, often occurring with a frequency of 100%. This could be of importance if a monovalent F protein from the historical GA1 genotype of RSV/A is used for vaccine development.


Assuntos
Genes Virais , Vírus Sincicial Respiratório Humano/genética , Sequência de Aminoácidos , Substituição de Aminoácidos , Anticorpos Antivirais/sangue , Variação Antigênica , Antígenos Virais/química , Antígenos Virais/genética , Variação Genética , Genótipo , Humanos , Conformação Proteica , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Infecções por Vírus Respiratório Sincicial/virologia , Vacinas contra Vírus Sincicial Respiratório/genética , Vacinas contra Vírus Sincicial Respiratório/imunologia , Vírus Sincicial Respiratório Humano/classificação , Vírus Sincicial Respiratório Humano/imunologia , Proteínas Virais de Fusão/química , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologia
12.
Nat Commun ; 8: 15773, 2017 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-28604738

RESUMO

Recent fate-mapping studies concluded that EMT is not required for metastasis of carcinomas. Here we challenge this conclusion by showing that these studies failed to account for possible crosstalk between EMT and non-EMT cells that promotes dissemination of non-EMT cells. In breast cancer models, EMT cells induce increased metastasis of weakly metastatic, non-EMT tumour cells in a paracrine manner, in part by non-cell autonomous activation of the GLI transcription factor. Treatment with GANT61, a GLI1/2 inhibitor, but not with IPI 926, a Smoothened inhibitor, blocks this effect and inhibits growth in PDX models. In human breast tumours, the EMT-transcription factors strongly correlate with activated Hedgehog/GLI signalling but not with the Hh ligands. Our findings indicate that EMT contributes to metastasis via non-cell autonomous effects that activate the Hh pathway. Although all Hh inhibitors may act against tumours with canonical Hh/GLI signalling, only GLI inhibitors would act against non-canonical EMT-induced GLI activation.


Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal , Metástase Neoplásica , Comunicação Parácrina , Proteína GLI1 em Dedos de Zinco/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Xenoenxertos , Humanos , Camundongos Endogâmicos NOD , Camundongos SCID , Piridinas/farmacologia , Pirimidinas/farmacologia , Microambiente Tumoral , Alcaloides de Veratrum/farmacologia , Proteína GLI1 em Dedos de Zinco/antagonistas & inibidores
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