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1.
EMBO J ; 38(4)2019 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-30643021

RESUMO

Organoids are self-organizing 3D structures grown from stem cells that recapitulate essential aspects of organ structure and function. Here, we describe a method to establish long-term-expanding human airway organoids from broncho-alveolar resections or lavage material. The pseudostratified airway organoids consist of basal cells, functional multi-ciliated cells, mucus-producing secretory cells, and CC10-secreting club cells. Airway organoids derived from cystic fibrosis (CF) patients allow assessment of CFTR function in an organoid swelling assay. Organoids established from lung cancer resections and metastasis biopsies retain tumor histopathology as well as cancer gene mutations and are amenable to drug screening. Respiratory syncytial virus (RSV) infection recapitulates central disease features, dramatically increases organoid cell motility via the non-structural viral NS2 protein, and preferentially recruits neutrophils upon co-culturing. We conclude that human airway organoids represent versatile models for the in vitro study of hereditary, malignant, and infectious pulmonary disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Fibrose Cística/patologia , Células Epiteliais/patologia , Técnicas de Cultura de Órgãos/métodos , Organoides/patologia , Infecções por Vírus Respiratório Sincicial/patologia , Sistema Respiratório/patologia , Animais , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Células Cultivadas , Fibrose Cística/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Modelos Animais de Doenças , Ensaios de Seleção de Medicamentos Antitumorais , Células Epiteliais/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Organoides/metabolismo , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Sistema Respiratório/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
2.
BMC Infect Dis ; 20(1): 450, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32591017

RESUMO

BACKGROUND: Respiratory syncytial virus (RSV) is a global cause of severe respiratory morbidity and mortality in infants. While preventive and therapeutic interventions are being developed, including antivirals, vaccines and monoclonal antibodies, little is known about the global molecular epidemiology of RSV. INFORM is a prospective, multicenter, global clinical study performed by ReSViNET to investigate the worldwide molecular diversity of RSV isolates collected from children less than 5 years of age. METHODS: The INFORM study is performed in 17 countries spanning all inhabited continents and will provide insight into the molecular epidemiology of circulating RSV strains worldwide. Sequencing of > 4000 RSV-positive respiratory samples is planned to detect temporal and geographical molecular patterns on a molecular level over five consecutive years. Additionally, RSV will be cultured from a subset of samples to study the functional implications of specific mutations in the viral genome including viral fitness and susceptibility to different monoclonal antibodies. DISCUSSION: The sequencing and functional results will be used to investigate susceptibility and resistance to novel RSV preventive or therapeutic interventions. Finally, a repository of globally collected RSV strains and a database of RSV sequences will be created.


Assuntos
Genoma Viral , Epidemiologia Molecular/métodos , Polimorfismo Genético , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/prevenção & controle , Vírus Sincicial Respiratório Humano/genética , Anticorpos Monoclonais/uso terapêutico , Antivirais/efeitos adversos , Antivirais/uso terapêutico , Pré-Escolar , Farmacorresistência Bacteriana/genética , Feminino , Genótipo , Humanos , Imunização Passiva , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
3.
Am J Respir Cell Mol Biol ; 58(4): 492-499, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29141155

RESUMO

Severe influenza virus infection can lead to life-threatening pathology through immune-mediated tissue damage. In various experimental models, this damage is dependent on T cells. There is conflicting evidence regarding the role of neutrophils in influenza-mediated pathology. Neutrophils are often regarded as cells causing tissue damage, but, in recent years, it has become clear that a subset of human neutrophils is capable of suppressing T cells, which is dependent on macrophage-1 antigen (CD11b/CD18). Therefore, we tested the hypothesis that immune suppression by neutrophils can reduce T cell-mediated pathology after influenza infection. Wild-type (WT) and CD11b-/- mice were infected with A/HK/2/68 (H3N2) influenza virus. Disease severity was monitored by weight loss, leukocyte infiltration, and immunohistochemistry. We demonstrated that CD11b-/- mice suffered increased weight loss compared with WT animals upon infection with influenza virus. This was accompanied by increased pulmonary leukocyte infiltration and lung damage. The exaggerated pathology in CD11b-/- mice was dependent on T cells, as it was reduced by T cell depletion. In addition, pathology in CD11b-/- mice was accompanied by higher numbers of T cells in the lungs early during infection compared with WT mice. Importantly, these differences in pathology were not associated with an increased viral load, suggesting that pathology was immune-mediated rather than caused by virus-induced damage. In contrast to adoptive transfer of CD11b-/- neutrophils, a single adoptive transfer of WT neutrophils partly restored protection against influenza-induced pathology, demonstrating the importance of neutrophil CD11b/CD18. Our data show that neutrophil CD11b/CD18 limits pathology in influenza-induced, T cell-mediated disease.


Assuntos
Antígeno CD11b/metabolismo , Antígenos CD18/metabolismo , Vírus da Influenza A/patogenicidade , Pulmão/metabolismo , Antígeno de Macrófago 1/metabolismo , Neutrófilos/metabolismo , Infecções por Orthomyxoviridae/metabolismo , Transferência Adotiva , Animais , Antígeno CD11b/genética , Antígeno CD11b/imunologia , Antígenos CD18/imunologia , Quimiotaxia de Leucócito , Modelos Animais de Doenças , Feminino , Interações Hospedeiro-Patógeno , Vírus da Influenza A/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Antígeno de Macrófago 1/genética , Antígeno de Macrófago 1/imunologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neutrófilos/imunologia , Neutrófilos/transplante , Neutrófilos/virologia , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Transdução de Sinais , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/virologia , Fatores de Tempo , Carga Viral , Redução de Peso
4.
J Virol ; 87(14): 8213-26, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23698290

RESUMO

Genomic variation and related evolutionary dynamics of human respiratory syncytial virus (RSV), a common causative agent of severe lower respiratory tract infections, may affect its transmission behavior. RSV evolutionary patterns are likely to be influenced by a precarious interplay between selection favoring variants with higher replicative fitness and variants that evade host immune responses. Studying RSV genetic variation can reveal both the genes and the individual codons within these genes that are most crucial for RSV survival. In this study, we conducted genetic diversity and evolutionary rate analyses on 36 RSV subgroup B (RSV-B) whole-genome sequences. The attachment protein, G, was the most variable protein; accordingly, the G gene had a higher substitution rate than other RSV-B genes. Overall, less genetic variability was found among the available RSV-B genome sequences than among RSV-A genome sequences in a comparable sample. The mean substitution rates of the two subgroups were, however, similar (for subgroup A, 6.47 × 10(-4) substitutions/site/year [95% credible interval {CI 95%}, 5.56 × 10(-4) to 7.38 × 10(-4)]; for subgroup B, 7.76 × 10(-4) substitutions/site/year [CI 95%, 6.89 × 10(-4) to 8.58 × 10(-4)]), with the time to their most recent common ancestors (TMRCAs) being much lower for RSV-B (19 years) than for RSV-A (46.8 years). The more recent RSV-B TMRCA is apparently the result of a genetic bottleneck that, over longer time scales, is still compatible with neutral population dynamics. Whereas the immunogenic G protein seems to require high substitution rates to ensure immune evasion, strong purifying selection in conserved proteins such as the fusion protein and nucleocapsid protein is likely essential to preserve RSV viability.


Assuntos
Evolução Molecular , Variação Genética/genética , Genômica/métodos , Filogenia , Vírus Sincicial Respiratório Humano/genética , Sequência de Aminoácidos , Sequência de Bases , Teorema de Bayes , Evasão da Resposta Imune/genética , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Dinâmica Populacional , Seleção Genética , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie , Replicação Viral/genética
6.
Arch Virol ; 158(1): 251-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23053517

RESUMO

Novel viruses might be responsible for numerous disease cases with unknown etiology. In this study, we screened 1800 nasopharyngeal samples from adult outpatients with respiratory disease symptoms and healthy individuals. We employed a reverse transcription (RT)-PCR assay and CODEHOP-based primers (CT12-mCODEHOP) previously developed to recognize known and unknown corona- and toroviruses. The CT12-mCODEHOP assay detected 42.0 % (29/69) of samples positive for human coronaviruses (HCoV), including HCoV-229 (1/16), HCoV-NL63 (9/17), and HCoV-OC43 (19/36), and additionally HCoV-HKU1 (3), which was not targeted by the diagnostic real-time PCR assays. No other coronaviruses were identified in the analyzed samples.


Assuntos
Coronavirus/isolamento & purificação , Primers do DNA/genética , Nasofaringe/virologia , Infecções Respiratórias/virologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Coronavirus/classificação , Coronavirus/genética , Humanos , Infecções Respiratórias/diagnóstico
7.
Microbiol Spectr ; 11(4): e0006323, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37404183

RESUMO

The gut microbiome of humans and animals acts as a reservoir of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-EC). Dogs are known for having a high prevalence of ESBL-EC in their gut microbiota, although their ESBL-EC carrier status often shifts over time. We hypothesized that the gut microbiome composition of dogs is implicated in ESBL-EC colonization status. Therefore, we assessed whether ESBL-EC carriage in dogs is associated with changes in the gut microbiome and resistome. Fecal samples were collected longitudinally from 57 companion dogs in the Netherlands every 2 weeks for a total of 6 weeks (n = 4 samples/dog). Carriage of ESBL-EC was determined through selective culturing and PCR and in line with previous studies, we observed a high prevalence of ESBL-EC carriage in dogs. Using 16s rRNA gene profiling we found significant associations between detected ESBL-EC carriage and an increased abundance of Clostridium sensu stricto 1, Enterococcus, Lactococcus, and the shared genera of Escherichia-Shigella in the dog microbiome. A resistome capture sequencing approach (ResCap) furthermore, revealed associations between detected ESBL-EC carriage and the increased abundance of the antimicrobial resistance genes: cmlA, dfrA, dhfR, floR, and sul3. In summary, our study showed that ESBL-EC carriage is associated with a distinct microbiome and resistome composition. IMPORTANCE The gut microbiome of humans and animals is an important source of multidrug resistant pathogens, including beta-lactamase-producing Escherichia coli (ESBL-EC). In this study, we assessed if the carriage of ESBL-EC in dogs was associated with changes in gut composition of bacteria and antimicrobial resistant genes (ARGs). Therefore, stool samples from 57 dogs were collected every 2 weeks for a total of 6 weeks. Sixty eight percent of the dogs carried ESBL-EC during at least one of the time points analyzed. By investigating the gut microbiome and resistome composition, we observed specific changes at time points when dogs were colonized with ESBL-EC compared to time points whenESBL-EC were not detected. In conclusion, our study highlights the importance to study the microbial diversity in companion animals, as gut colonization of particular antimicrobial resistant bacteria might be an indication of a changed microbial composition that is associated with the selection of particular ARGs.


Assuntos
Infecções por Escherichia coli , Microbioma Gastrointestinal , Humanos , Cães , Animais , Infecções por Escherichia coli/microbiologia , Proteínas de Bactérias/genética , RNA Ribossômico 16S/genética , Escherichia coli/genética , beta-Lactamases/genética , Bactérias/genética , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Antibacterianos/farmacologia
8.
Microbiol Spectr ; 11(6): e0127523, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37888982

RESUMO

IMPORTANCE: Colonization with extended-spectrum beta-lactamase-producing Enterobacterales (ESBL-PE) often precedes infections and is therefore considered as a great threat for public health. Here, we studied the gut microbiome dynamics in eight index patients colonized with ESBL-PE after hospital discharge and the impact of exposure to this index patient on the gut microbiome dynamics of their household contacts. We showed that the microbiome composition from index patients is different from their household contacts upon hospital discharge and that, in some of the index patients, their microbiome composition over time shifted toward the composition of their household contacts. In contrast, household contacts showed a stable microbiome composition over time irrespective of low-level extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-Ec) or extended-spectrum beta-lactamase-producing Klebsiella pneumoniae (ESBL-Kp) gut colonization, suggesting that, in healthy microbiomes, colonization resistance is able to prevent ESBL-PE expansion.


Assuntos
Microbioma Gastrointestinal , Humanos , Alta do Paciente , beta-Lactamases , Escherichia coli , Klebsiella pneumoniae , Hospitais , Antibacterianos
9.
Sci Rep ; 13(1): 3444, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859567

RESUMO

The endometrial microbiota composition may be associated with implantation success. However, a 'core' composition has not yet been defined. This exploratory study analysed the endometrial microbiota by 16S rRNA sequencing (V1-V2 region) of 141 infertile women whose first IVF/ICSI cycle failed and compared the microbiota profiles of women with and without a live birth within 12 months of follow-up, and by infertility cause and type. Lactobacillus was the most abundant genus in the majority of samples. Women with a live birth compared to those without had significantly higher Lactobacillus crispatus relative abundance (RA) (p = 0.029), and a smaller proportion of them had ≤ 10% L. crispatus RA (42.1% and 70.4%, respectively; p = 0.015). A smaller proportion of women in the male factor infertility group had ≤ 10% L. crispatus RA compared to women in the unexplained and other infertility causes groups combined (p = 0.030). Women with primary infertility compared to secondary infertility had significantly higher L. crispatus RA (p = 0.004); lower proportions of them had ≤ 10% L. crispatus RA (p = 0.009) and > 10% Gardnerella vaginalis RA (p = 0.019). In conclusion, IVF/ICSI success may be associated with L. crispatus RA and secondary infertility with endometrial dysbiosis, more often than primary infertility. These hypotheses should be tested in rigorous well-powered longitudinal studies.


Assuntos
Infertilidade Feminina , Infertilidade Masculina , Microbiota , Humanos , Feminino , Masculino , Gravidez , Nascido Vivo , RNA Ribossômico 16S , Injeções de Esperma Intracitoplásmicas
10.
J Immunol ; 185(11): 6489-98, 2010 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-20971927

RESUMO

Following infection with respiratory syncytial virus (RSV), reinfection in healthy individuals is common and presumably due to ineffective memory T cell responses. In peripheral blood of healthy adults, a higher CD4(+)/CD8(+) memory T cell ratio was observed compared with the ratio of virus-specific effector CD4(+)/CD8(+) T cells that we had found in earlier work during primary RSV infections. In mice, we show that an enhanced ratio of RSV-specific neutralizing to nonneutralizing Abs profoundly enhanced the CD4(+) T cell response during RSV infection. Moreover, FcγRs and complement factor C1q contributed to this Ab-mediated enhancement. Therefore, the increase in CD4(+) memory T cell response likely occurs through enhanced endosomal Ag processing dependent on FcγRs. The resulting shift in memory T cell response was likely amplified by suppressed T cell proliferation caused by RSV infection of APCs, a route important for Ag presentation via MHC class I molecules leading to CD8(+) T cell activation. Decreasing memory CD8(+) T cell numbers could explain the inadequate immunity during repeated RSV infections. Understanding this interplay of Ab-mediated CD4(+) memory T cell response enhancement and infection mediated CD8(+) memory T cell suppression is likely critical for development of effective RSV vaccines.


Assuntos
Anticorpos Antivirais/sangue , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Vírus Sinciciais Respiratórios/imunologia , Imunidade Adaptativa , Animais , Apresentação de Antígeno/imunologia , Linfócitos T CD4-Positivos/patologia , Células Cultivadas , Células Dendríticas/imunologia , Células Dendríticas/patologia , Células Dendríticas/virologia , Epitopos de Linfócito T/imunologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células NIH 3T3 , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/patologia
12.
Sci Rep ; 12(1): 1892, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-35115599

RESUMO

The human gut microbiome plays a central role in health and disease. Environmental factors, such as lifestyle and diet, are known to shape the gut microbiome as well as the reservoir of resistance genes that these microbes harbour; the resistome. In this study we assessed whether long-term dietary habits within a single geographical region (the Netherlands) impact the human gut resistome. Faecal samples from Dutch omnivores, pescatarians, vegetarians and vegans were analysed by metagenomic shotgun sequencing (MSS) (n = 149) and resistome capture sequencing approach (ResCap) (n = 64). Among all diet groups, 119 and 145 unique antibiotic resistance genes (ARGs) were detected by MSS or ResCap, respectively. Five or fifteen ARGs were shared between all diet groups, based on MSS and ResCap, respectively. The total number of detected ARGs by MSS or ResCap was not significantly different between the groups. MSS also revealed that vegans have a distinct microbiome composition, compared to other diet groups. Vegans had a lower abundance of Streptococcus thermophilus and Lactococcus lactis compared to pescatarians and a lower abundance of S. thermophilus when compared to omnivores. In summary, our study showed that long-term dietary habits are not associated with a specific resistome signature.


Assuntos
Bactérias/genética , Dieta , Farmacorresistência Bacteriana/genética , Comportamento Alimentar , Microbioma Gastrointestinal , Trato Gastrointestinal/microbiologia , Adulto , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Dieta Vegana , Dieta Vegetariana , Fezes/microbiologia , Feminino , Humanos , Masculino , Carne , Metagenoma , Metagenômica , Pessoa de Meia-Idade , Países Baixos , Valor Nutritivo , Alimentos Marinhos , Fatores de Tempo , Verduras
13.
Environ Int ; 169: 107497, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36088872

RESUMO

Air pollution from livestock farms is known to affect respiratory health of patients with chronic obstructive pulmonary disease (COPD). The mechanisms behind this relationship, however, remain poorly understood. We hypothesise that air pollutants could influence respiratory health through modulation of the airway microbiome. Therefore, we studied associations between air pollution exposure and the oropharyngeal microbiota (OPM) composition of COPD patients and controls in a livestock-dense area. Oropharyngeal swabs were collected from 99 community-based (mostly mild) COPD cases and 184 controls (baseline), and after 6 and 12 weeks. Participants were non-smokers or former smokers. Annual average livestock-related outdoor air pollution at the home address was predicted using dispersion modelling. OPM composition was analysed using 16S rRNA-based sequencing in all baseline samples and 6-week and 12-week repeated samples of 20 randomly selected subjects (n = 323 samples). A random selection of negative control swabs, taken every sampling day, were also included in the downstream analysis. Both farm-emitted endotoxin and PM10 levels were associated with increased OPM richness in COPD patients (p < 0.05) but not in controls. COPD case-control status was not associated with community structure, while correcting for known confounders (multivariate PERMANOVA p > 0.05). However, members of the genus Streptococcus were more abundant in COPD patients (Benjamini-Hochberg adjusted p < 0.01). Moderate correlation was found between ordinations of 20 subjects analysed at 0, 6, and 12 weeks (Procrustes r = 0.52 to 0.66; p < 0.05; Principal coordinate analysis of Bray-Curtis dissimilarity), indicating that the OPM is relatively stable over a 12 week period and that a single sample sufficiently represents the OPM. Air pollution from livestock farms is associated with OPM richness of COPD patients, suggesting that the OPM of COPD patients is susceptible to alterations induced by exposure to air pollutants.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Microbiota , Doença Pulmonar Obstrutiva Crônica , Poluentes Atmosféricos/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Animais , Endotoxinas/análise , Fazendas , Humanos , Gado , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética
14.
Elife ; 112022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34989676

RESUMO

Implant-associated Staphylococcus aureus infections are difficult to treat because of biofilm formation. Bacteria in a biofilm are often insensitive to antibiotics and host immunity. Monoclonal antibodies (mAbs) could provide an alternative approach to improve the diagnosis and potential treatment of biofilm-related infections. Here, we show that mAbs targeting common surface components of S. aureus can recognize clinically relevant biofilm types. The mAbs were also shown to bind a collection of clinical isolates derived from different biofilm-associated infections (endocarditis, prosthetic joint, catheter). We identify two groups of antibodies: one group that uniquely binds S. aureus in biofilm state and one that recognizes S. aureus in both biofilm and planktonic state. Furthermore, we show that a mAb recognizing wall teichoic acid (clone 4497) specifically localizes to a subcutaneously implanted pre-colonized catheter in mice. In conclusion, we demonstrate the capacity of several human mAbs to detect S. aureus biofilms in vitro and in vivo.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Biofilmes , Staphylococcus aureus/imunologia , Animais , Infecções Relacionadas a Cateter/imunologia , Infecções Relacionadas a Cateter/microbiologia , Infecções Relacionadas a Cateter/terapia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estafilocócicas/microbiologia , Ácidos Teicoicos/imunologia , Ácidos Teicoicos/metabolismo
15.
J Virol ; 84(5): 2374-83, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20015982

RESUMO

Severe primary respiratory syncytial virus (RSV) infections are characterized by bronchiolitis accompanied by wheezing. Controversy exists as to whether infants suffer from virus-induced lung pathology or from excessive immune responses. Furthermore, detailed knowledge about the development of primary T-cell responses to viral infections in infants is lacking. We studied the dynamics of innate neutrophil and adaptive T-cell responses in peripheral blood in relation to the viral load and parameters of disease in infants admitted to the intensive care unit with severe RSV infection. Analysis of primary T-cell responses showed substantial CD8(+) T-cell activation, which peaked during convalescence. A strong neutrophil response, characterized by mobilization of bone marrow-derived neutrophil precursors, preceded the peak in T-cell activation. The kinetics of this neutrophil response followed the peak of clinical symptoms and the viral load with a 2- to 3-day delay. From the sequence of events, we conclude that CD8(+) T-cell responses, initiated during primary RSV infections, are unlikely to contribute to disease when it is most severe. The mobilization of precursor neutrophils might reflect the strong neutrophil influx into the airways, which is a characteristic feature during RSV infections and might be an integral pathogenic process in the disease.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Ativação Linfocitária/imunologia , Neutrófilos/imunologia , Infecções por Vírus Respiratório Sincicial/imunologia , Vírus Sincicial Respiratório Humano/imunologia , Feminino , Humanos , Lactente , Masculino , RNA Viral/metabolismo , Respiração Artificial , Infecções por Vírus Respiratório Sincicial/fisiopatologia , Índice de Gravidade de Doença , Carga Viral
16.
J Clin Microbiol ; 48(10): 3569-74, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20660210

RESUMO

Quantitative real-time PCR for the detection of respiratory syncytial virus (RSV) RNA is increasingly used to study the causal role of RSV in lower airway disease. The objective of our study was to evaluate variations in RSV RNA loads at different steps in the RNA quantification process: (i) variation in RSV RNA load within one sample (step 1), (ii) variation in the load in samples from patients who were sampled twice on the same day (step 2), and (iii) variation in the load between simultaneously taken nasopharyngeal aspirate (NPA) samples and tracheal aspirate (TA) samples (step 3). Thirty-two infants with RSV infection at the pediatric intensive care unit (PICU) were included. NPA and TA samples were taken three times a week during ventilation and were not diluted. Intrasample variation (step 1) was shown to be minimal (<0.5 log(10) particles/ml). Intraday variation (step 2) was the lowest for samples with high viral loads (95% limits of agreement, -1.3 to +0.9 log(10)), whereas it increased for samples with relatively lower viral loads (viral load, <6.0 log(10) particles/ml; n = 138 sample pairs from 20 patients). RSV loads in NPA and TA samples (step 3) were found to be the most comparable during the early phase of infection (95% limits of agreement, -1.5 to +1.4 log(10)). The variation increased during the late phase of infection (i.e., in follow-up samples), with the loads in NPA samples remaining significantly higher than the loads in TA samples (n = 138 sample pairs from 31 patients). In conclusion, quantitative detection of RSV RNA in undiluted mucus is a reliable method to quantify viral loads. Nasopharyngeal aspirate samples collected in the initial phase of infection can be used to predict RSV RNA loads in the lower airways.


Assuntos
RNA Viral/genética , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Carga Viral , Virologia/métodos , Humanos , Lactente , Muco/virologia , Nasofaringe/virologia , Traqueia/virologia
17.
Front Immunol ; 11: 1245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32636843

RESUMO

Common Variable Immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA) are primary antibody deficiencies characterized by hypogammaglobulinemia and recurrent infections, which can lead to structural airway disease (AD) and interstitial lung disease (ILD). We investigated associations between serum IgA, oropharyngeal microbiota composition and severity of lung disease in these patients. In this cross-sectional multicentre study we analyzed oropharyngeal microbiota composition of 86 CVID patients, 12 XLA patients and 49 healthy controls (HC) using next-generation sequencing of the 16S rRNA gene. qPCR was used to estimate bacterial load. IgA was measured in serum. High resolution CT scans were scored for severity of AD and ILD. Oropharyngeal bacterial load was increased in CVID patients with low IgA (p = 0.013) and XLA (p = 0.029) compared to HC. IgA status was associated with distinct beta (between-sample) diversity (p = 0.039), enrichment of (Allo)prevotella, and more severe radiographic lung disease (p = 0.003), independently of recent antibiotic use. AD scores were positively associated with Prevotella, Alloprevotella, and Selenomonas, and ILD scores with Streptococcus and negatively with Rothia. In clinically stable patients with CVID and XLA, radiographic lung disease was associated with IgA deficiency and expansion of distinct oropharyngeal bacterial taxa. Our findings highlight IgA as a potential driver of upper respiratory tract microbiota homeostasis.


Assuntos
Imunoglobulina A/imunologia , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/imunologia , Pneumopatias/imunologia , Orofaringe/microbiologia , Adolescente , Adulto , Criança , Estudos Transversais , Feminino , Humanos , Imunoglobulina A/sangue , Masculino , Adulto Jovem
18.
J Clin Virol ; 112: 20-26, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30708281

RESUMO

BACKGROUND: We found amino acid substitutions in the Gglycoprotein of respiratory syncytial virus (RSV) A during the 2016/2017 epidemic in The Netherlands. OBJECTIVES: We evaluated whether these alterations led to increased RSV incidence and disease burden. STUDY DESIGN: We sequenced the gene encoding the G-protein of prospectively collected clinical specimens from secondary care adult patients testing positive for RSV during the 2016/2017 and 2017/2018 epidemic RSV season. We evaluated associations between genetic, clinical and epidemiological data. RESULTS: We included 49 RSV strains. In 2016/2017 28 strains were included, 20 community acquired RSV-A, 5 hospital acquired RSV-A and 3 community acquired RSV-B. In 2017/2018 21 strains were included, 8 community acquired RSV-A and 13 community acquired RSV-B. G-proteins of 10 out of the 20 community acquired 2016/2017 RSV-A strains shared a set of eight novel amino acid substitutions of which seven in mucin-like regions 1 and 2 and one in the heparin binding domain. This genetic variant was no longer detected among 2017/2018 RSV-A strains. Among patients carrying the novel RSV-A strain-type, 30% died. CONCLUSIONS: A set of eight amino acid substitutions was found in 50% of the 2016/2017 community acquired RSV-A G-proteins. This combination of substitutions was globally never observed before. The appearance of this new strain-type coincided with an increased RSV peak in The Netherlands and was associated with higher disease severity. The transient character of this epidemic strain-type suggests rapid clearance of this lineage in our study community.


Assuntos
Substituição de Aminoácidos , Variação Genética , Infecções por Vírus Respiratório Sincicial/epidemiologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/genética , Proteínas Virais de Fusão/genética , Adulto , Idoso , Epidemias/estatística & dados numéricos , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Países Baixos/epidemiologia , Filogenia , RNA Viral/genética , Vírus Sincicial Respiratório Humano/patogenicidade , Análise de Sequência de DNA
19.
Microbiologyopen ; 8(12): e936, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31568701

RESUMO

The aim of this study was to determine whether dietary intervention influenced luminal Ca2+ levels and Enterococcus faecium gut colonization in mice. For this purpose, mice fed semi-synthetic food AIN93 were compared to mice fed AIN93-low calcium (LC). Administration of AIN93-LC resulted in lower luminal Ca2+ levels independent of the presence of E. faecium. Furthermore, E. faecium gut colonization was reduced in mice fed AIN93-LC based on culture, and which was in concordance with a reduction of Enterococcaceae in microbiota analysis. In conclusion, diet intervention might be a strategy for controlling gut colonization of E. faecium, an important opportunistic nosocomial pathogen.


Assuntos
Ração Animal , Cálcio , Suplementos Nutricionais , Enterococcus faecium/fisiologia , Microbioma Gastrointestinal , Animais , Biodiversidade , Cálcio/administração & dosagem , Fezes/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Camundongos , RNA Ribossômico 16S
20.
Sci Rep ; 9(1): 10979, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31358818

RESUMO

Bariatric surgery in morbid obesity, either through sleeve gastrectomy (SG) or Roux-Y gastric bypass (RYGB), leads to sustainable weight loss, improvement of metabolic disorders and changes in intestinal microbiota. Yet, the relationship between changes in gut microbiota, weight loss and surgical procedure remains incompletely understood. We determined temporal changes in microbiota composition in 45 obese patients undergoing crash diet followed by SG (n = 22) or RYGB (n = 23). Intestinal microbiota composition was determined before intervention (baseline, S1), 2 weeks after crash diet (S2), and 1 week (S3), 3 months (S4) and 6 months (S5) after surgery. Relative to S1, the microbial diversity index declined at S2 and S3 (p < 0.05), and gradually returned to baseline levels at S5. Rikenellaceae relative abundance increased and Ruminococcaceae and Streptococcaceae abundance decreased at S2 (p < 0.05). At S3, Bifidobacteriaceae abundance decreased, whereas those of Streptococcaceae and Enterobacteriaceae increased (p < 0.05). Increased weight loss between S3-S5 was not associated with major changes in microbiota composition. No significant differences appeared between both surgical procedures. In conclusion, undergoing a crash diet and bariatric surgery were associated with an immediate but temporary decline in microbial diversity, with immediate and permanent changes in microbiota composition, independent of surgery type.


Assuntos
Gastrectomia , Derivação Gástrica , Microbioma Gastrointestinal , Obesidade/dietoterapia , Obesidade/cirurgia , Adulto , Cirurgia Bariátrica , Feminino , Gastrectomia/métodos , Derivação Gástrica/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/microbiologia , Redução de Peso
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