Project description:While the majority of infants infected with respiratory syncytial virus (RSV) exhibit mild or no symptoms, approximately 3 million children under the age of five are hospitalized every year due to complications from RSV. This research sought to explore the biological processes and related biomarkers responsible for the varied manifestations of RSV disease in young infants. The goal is to pave the way for a more precise categorization of RSV-infected infants based on their medical requirements. Whole blood samples are collected from infant case-control cohort study, the RESCEU case-control cohort is a multinational, multicenter, observational study (clinical trial registration number: NCT03756766). Infants < 12 months old with RSV disease were recruited from the University Medical Center Utrecht (UMCU) in The Netherlands, Hospital Clínico Universitario de Santiago (SERGAS) in Spain, Imperial College (IMPERIAL) National Health Service Trust (NHS) and Oxford University Hospital NHS Trust (OXFORD) in the United Kingdom during the RSV seasons 2017-2018, 2018-2019, and 2019-2020. Healthy controls without underlying comorbidities were recruited outside of the RSV season. Eligibility criteria included hospitalization for less than 48 hours at enrolment or within 96 hours of disease onset, no previous receipt of medications to treat RSV infection, no prior exposure to an investigational RSV vaccine or medication, no previous receipt of immunoglobulins or monoclonal antibodies, and had not used montelukast or oral steroids within seven days before enrolment. Infants with co-morbidities were not evaluated in the manuscript. RSV was detected using RSV point-of-care test (POCT) by either a rapid antigen detection test (Alere I) (Alere Inc, Waltham, Massachusetts) or rapid RSV polymerase chain reaction (PCR) test at the hospital setting, or a RSV PCR test at the laboratory. Convalescence samples were collected 7 ±1 weeks after a positive RSV diagnostic test result. We used microarray to assist us to identify biomarkers for severe RSV disease.
Project description:The aim of this investigation was two-fold: i) to describe miRNAs involved in the immune response to Respiratory syncytial virus (RSV) in a clinical setting in order to inform further research of immune system regulation by miRNAs in RSV or other infections; ii) to discover differences in miRNA expression between disease severity groups. We have therefore profiled miRNA in cytology brushings of the nasal mucosa in infants with RSV disease, comparing them to healthy infants. miRNA microarray identified 26 differentially regulated miRNA which were subsequently analyzed by RT-qPCR.
Project description:In this study we investigated whether there exists a genomic signature that can accurately predict the course of a respiratory syncytial virus (RSV) infection in hospitalized young infants. We used early blood microarray transcriptome profiles from 39 infants that were followed until recovery and of which the level of disease severity was determined retrospectively. Applying support vector machine learning on age by sex standardized transcriptomic data, an 84 gene signature was identified that discriminated hospitalized infants with eventually less severe RSV infection from infants that suffered from most severe RSV disease.
Project description:Rationale: Respiratory syncytial virus (RSV) is the leading cause of acute lower respiratory tract infections and hospitalizations in infants worldwide. Known risk factors, however, incompletely explain the variability of RSV disease severity among children. We postulate that severity of RSV infection is influenced in part by modulation of the host immune response by the local microbial ecosystem at the time of infection. Objectives: To define whether different nasopharyngeal microbiota profiles are associated with distinct host transcriptome profiles and severity in children with RSV infection. Methods: We analyzed the nasopharyngeal microbiota profiles of young children with mild and severe RSV disease and healthy matched controls by 16S-rRNA sequencing. In parallel, we analyzed whole blood gene expression profiles to study the relationship between microbial community composition, the RSV-induced host transcriptional response and clinical disease severity. Measurements and Main results: We identified five nasopharyngeal microbiota profiles characterized by enrichment of H. influenzae, Streptococcus, Corynebacterium, Moraxella or S. aureus. RSV infection and RSV hospitalization were positively associated with H. influenzae and Streptococcus, and negatively associated with S. aureus abundance, independent of age. The host response to RSV was defined by overexpression of interferon-related genes, and this was independent of the microbiota composition. On the other hand, transcriptome profiles of RSV infected children with H. influenzae and Streptococcus-dominated microbiota were characterized by greater overexpression of genes linked to toll-like receptor-signaling and neutrophil activation and were more frequently hospitalized Conclusions: Our data suggest an immunomodulatory role for the resident nasopharyngeal microbial community early in RSV infection, potentially affecting RSV disease severity.
Project description:<p>A prospective multi-year clinical translational study including three cohorts of term infants experiencing their first Respiratory Syncytial Virus (RSV) season. All infants are less than or equal to nine months of age at study entry. The three subject cohorts represent the full spectrum of RSV disease severity and include a birth cohort, a cohort of infants hospitalized for RSV disease and infants evaluated at ambulatory settings for RSV infection. All infants are followed longitudinally and evaluated at recognition of acute RSV infection and twice during convalescence. Innate and adaptive immune status are comprehensively measured in association with clinical, environmental, viral, and bacteriologic factors. Genome-wide expression is assessed in the nasal airways, and in sorted peripheral blood lymphocytes. The study goal is to Identify host responses to RSV infection and factors associated with severe disease. </p>
Project description:Respiratory syncytial virus (RSV) selectively targets ciliated cells in human bronchial epithelium and can cause bronchiolitis and pneumonia mostly in infants. To identify molecular targets of intervention during RSV infection in infants, we investigate how age regulates RSV interaction with the bronchial epithelium barrier. Employing precision-cut lung slices and air-liquid interface cultures generated from infant and adult human donors, we found robust RSV virus spread and extensive apoptotic cell death only in infant bronchial epithelium. In contrast, adult bronchial epithelium showed insignificant barrier damage and limited RSV infection. Single nuclear RNA-sequencing revealed age-related insufficiency of an anti-apoptotic STAT3 activation response to RSV infection in infant ciliated cells, which was exploited to facilitate virus spread via the extruded apoptotic ciliated cells carrying RSV. Activation of STAT3 and blockade of apoptosis rendered protection against severe RSV infection in infant bronchial epithelium. Lastly, apoptotic inhibitor treatment of a neonatal mouse model of RSV infection ameliorated infection and inflammation in the lung. Taken together, our findings identify a STAT3-mediated anti-apoptosis pathway as a target to battle severe RSV disease in infants.
Project description:COVID-19 symptoms range from mild to severe illness; the cause for this differential response to infection remains unknown. Unraveling the immune mechanisms acting at different levels of the colonization process might be key to understand these differences. We carried out a multi-tissue (nasal, buccal and blood) gene expression analysis of immune-related genes from patients affected by different COVID-19 severities, and healthy controls.
Project description:Background: Chronic rhinosinusitis with nasal polyposis (CRSwNP) in western countries is characterized by eosinophilia, IgE production and Th2 cytokine expression. Type 2 innate lymphoid cells (ILC2) from polyps produce IL-5 and IL-13 in response to IL-25 and IL-33 although the relevance of this axis to local mucosal T cell responses is unknown. Objective: To investigate the role of the IL-25/IL-33 axis in local mucosal T cell responses in CRSwNP. Methods: Polyp tissue and blood were obtained from patients undergoing nasal polypectomy. Control nasal biopsies and blood were obtained from healthy volunteers. Tissue was cultured in a short-term explant model. T cell surface phenotype/intracellular cytokines were assessed by flow cytometry. TCR Vβ analysis was performed with the immunoSEQ assay. Microarrays were performed for gene expression analysis. Results: Using nasal polyp tissue, numerous IL-25 receptor (IL-17RB) positive polarized Th2 cells were identified which were absent in the healthy nasal mucosa and periphery. IL-17RB+CD4+ polyp Th2 cells co-expressed ST2 (IL-33 receptor) and responded to IL-25 and IL-33 with enhanced IL-5 and IL-13 production. Within IL-17RB+CD4+ T cells several identical TCR Vβ CDR3 sequences were identified in different subjects suggesting clonal expansion driven by a common antigen. Abundant IL-17 producing T cells were observed in healthy nasal mucosal and polyp populations with Th17-related genes the most overexpressed compared to peripheral blood T cells. Conclusion: IL-25 and IL-33 may interact locally with IL-17RB+ST2+ polyp T cells to augment Th2 responses in CRSwNP. A local Th17 response may be the default signature in healthy nasal mucosal immune homeostasis. Three biological replicates. T-helper cells were isolated nasal polyps by explant culture from patients with chronic rhinosinusitis. Cells were then sorted based upon expression of IL17RB by flow cytometric sorting. Resting and activated IL-17RB+ve cells were compared with resting and activated IL-17RB-ve cells.
Project description:Peripheral blood was collected from 87 patients with acute pancreatitis (AP) of varying severity (Mild=57, Moderately-Severe=20, Severe=10) within 24 hours of presentation to the hospital and from 32 healthy controls. RNA-Seq was performed to identify changes in expression in severe AP cf. mild, moderately-severe, and healthy controls.
Project description:Respiratory viral infections follow an unpredictable clinical course in young children ranging from a common cold to respiratory failure. The transition from mild to severe disease occurs rapidly and is difficult to predict. The pathophysiology underlying disease severity has remained elusive. There is an urgent need to better understand the immune response in this disease to come up with biomarkers that may aid clinical decision making. In a prospective study, flow cytometric and genome-wide gene expression analyses were performed on blood samples of 26 children with a diagnosis of severe, moderate or mild Respiratory Syncytial Virus (RSV) infection. Differentially expressed genes were validated using Q-PCR in a second cohort of 80 children during three consecutive winter seasons. FACS analyses were also performed in the second cohort and on recovery samples of severe cases in the first cohort. Severe RSV infection was associated with a transient but marked decrease in CD4+ T, CD8+ T, and NK cells in peripheral blood. Gene expression analyses in both cohorts identified Olfactomedin4 (OLFM4) as a fully discriminative marker between children with mild and severe RSV infection, giving a PAM cross-validation error of 0%. Patients with an OLFM4 gene expression level above -7.5 were 6 times more likely to develop severe disease, after correction for age at hospitalization and gestational age. In conclusion, by combining genome-wide expression profiling of blood cell subsets with clinically well-annotated samples, OLFM4 was identified as a biomarker for severity of pediatric RSV infection. Samples were taken of 26 patients with acute RSV infections, divided into mild (n=9), moderate (n=9) and severe (n=8) disease. From moderate and severe diseased patients recovery samples were obtained as well.