Project description:Background: Meningitis can be caused by several viruses and bacteria. Identifying the causative pathogen as quickly as possible is crucial to initiate the most optimal therapy, as acute bacterial meningitis is associated with a significant morbidity and mortality. Bacterial meningitis requires antibiotics, as opposed to enteroviral meningitis, which only requires supportive therapy. Clinical presentation is usually not sufficient to differentiate between viral and bacterial meningitis, thereby necessitating cerebrospinal fluid (CSF) analysis by PCR and/or time-consuming bacterial cultures. However, collecting CSF in children is not always feasible and a rather invasive procedure. Methods: In 12 Belgian hospitals, we obtained acute blood samples from children with signs of meningitis (49 viral and 7 bacterial cases). (aged between 3 months and 16 years). After pathogen confirmation on CSF, the patient was asked to give a convalescent sample after recovery. 3’mRNA sequencing was performed to determine differentially expressed genes (DEGs) to create a host transcriptomic profile. Results: Enteroviral meningitis cases displayed the largest upregulated fold change enrichment in type I interferon production, response and signaling pathways. Patients with bacterial meningitis showed a significant upregulation of genes related to macrophage and neutrophil activation. We found several significantly DEGs between enteroviral and bacterial meningitis. Random forest classification showed that we were able to differentiate enteroviral from bacterial meningitis with an AUC of 0.982 on held-out samples. Conclusions: Enteroviral meningitis has an innate immunity signature with type 1 interferons as key players. Our classifier, based on blood host transcriptomic profiles of different meningitis cases, is a possible strong alternative for diagnosing enteroviral meningitis.
Project description:Multiomics of faecal samples collected from individuals in families with multiple cases of type 1 diabetes mellitus (T1DM) over 3 or 4 months. Metagenomic and metatranscriptomic sequencing and metaproteomics were carried out, as well as whole human genome sequencing. Phenotypic data is available.
Project description:Multiomics of faecal samples collected from individuals in families with multiple cases of type 1 diabetes mellitus (T1DM) over 3 or 4 months. Metagenomic and metatranscriptomic sequencing and metaproteomics were carried out, as well as whole human genome sequencing. Phenotypic data is available.
Project description:Meningitis is a life-threatening condition characterized by the inflammation of the leptomeningeal membranes surrounding the brain and spinal cord. The term meningitis is an umbrella term and includes several different etiologies. The majorities of meningitis cases are caused by viruses (viral meningitis; VM) and are often associated with low mortality rates and low risk of developing neurological. In contrast, meningitis caused by some viral infections, such as tick-borne encephalitis (TBE), can be life-threatening when left untreated with increased risk of developing neurological sequelae. Acute bacterial meningitis (ABM), however, is one of the leading causes of death due to infectious diseases worldwide and is associated with rapid disease progression, high mortality rates and increased risk of long-term neurological sequelae in survivors. As meningitis is caused by numerous different pathogens, the host-response is typically highly variable and it is currently unknown if different pathogens can introduce specific proteome changes in the cerebrospinal fluid (CSF). In this study we applied DIA-MS to provide novel insights for in-depth understanding of central nervous system functioning and host response during meningitis in a cohort of patients with differential diagnosis of meningitis, to account for variability contributed by different disease-causing pathogens. The results reveal drastic changes in the CSF proteome during meningitis, where in particular a massive increase of neutrophil derived proteins in the CSF correlated with ABM, suggesting that activated neutrophils play a particular role in ABM. Additionally both ABM and VM result in marked reduction of brain-specific proteins in the CSF, which could be indicative of pathophysiological mechanisms leading to brain damage. Furthermore, generation of lasso regression model enables separation of ABM with high sensitivity and specificity, demonstrating that several proteins are required to confidently discriminate between ABM, VM and BM.
Project description:We applied genomic array footprinting (GAF) in the search for genes of S. pneumoniae essential during the establishment and progression of experimental meningitis. Four libraries with a total of 6,000 independent TIGR4 marinerT7 transposon mutants were injected intra-cisternally in rabbits, and cerebrospinal fluid (CSF) was collected after three, nine, and fifteen hours. Microarray analysis of mutant-specific probes from CSF samples and inocula identified 82 genes of which mutants had become attenuated and eleven genes of which mutants had become enriched during infection. Screening results particularly point to an essential role for capsular polysaccharides (cps), nutrient uptake, and metabolism in meningitis. Detailed study on directed mutants of a subset of sixteen GAF targets in an experimental model of rat meningitis revealed that ten were significantly attenuated or enriched during competitive infection. Furthermore, we showed that mutants of adenylosuccinate synthetase (purA), flavodoxin (fld), and the substrate binding protein (livJ) of a branched chain amino acid ABC-transporter were essential for full blown meningitis in a mono-infection setup of rat meningitis. Overall, the GAF screen revealed the general restraint on nutrients encountered by the pneumococcus in CSF, while, except for cps genes, no ‘classic’ virulence factors appeared to be required for infection. This knowledge will contribute to a better understanding of the molecular pathogenesis of pneumococcal meningitis.
Project description:Meningitis is a life-threatening condition characterized by the inflammation of the leptomeningeal membranes surrounding the brain and spinal cord. The term meningitis is an umbrella term and includes several different etiologies. Acute bacterial meningitis (ABM) is one of the leading causes of death due to infectious diseases worldwide and is associated with rapid disease progression, high mortality rates and increased risk of long-term neurological sequelae in survivors. As meningitis is caused by numerous different pathogens, the host-response is typically highly variable and it is currently unknown if different pathogens can introduce specific proteome changes in the cerebrospinal fluid (CSF). By using LC-MS/MS we have generated assay libraries of 8 unique bacterial strains that commonly cause meningitis. These libraries can be used to mine CSF of meningitis samples to detect bacterial peptides.
Project description:Tuberculous meningitis is one of the fatal forms of extra pulmonary disease associated with high mortality and severe neurological defects in affected individuals. We have carried out transcriptome level analysis using whole human genome microarrays to identify differential expression of genes between tuberculous meningitis and normals. In our gene expression analysis, we found 2,434 genes that were differentially erexpressed with 2 or more than 2 fold changes between tuberculous meningitis compared to normal cases. Most of the genes encoded many of the proteins, which involves metabolism, energy pathways, cell growth and/or maintenance, transport and cell communication and signal transduction. We have performed immunohistochemistry for the validation of some of the novel candidates identified in our microarray studies.!Series_overall_design = Present study carried out mRNA expression profiling of five samples from patients diagnosed with tuberculous meningitis and four head injury cases were used as controls. We have used 4X44K arrays from agilent plaform. To validate our microarray results, we have done Immunohistochemistry on 15 TBM cases with control groups. Present study carried out mRNA expression profiling of five samples from patients diagnosed with tuberculous meningitis and four head injury cases were used as controls. We have used 4X44K arrays from agilent plaform. To validate our microarray results, we have done Immunohistochemistry on 15 TBM cases with control groups.!Series_type = Expression profiling by array
Project description:Tuberculous meningitis is one of the fatal forms of extra pulmonary disease associated with high mortality and severe neurological defects in affected individuals. We have carried out transcriptome level analysis using whole human genome microarrays to identify differential expression of genes between tuberculous meningitis and normals. In our gene expression analysis, we found 2,434 genes that were differentially erexpressed with 2 or more than 2 fold changes between tuberculous meningitis compared to normal cases. Most of the genes encoded many of the proteins, which involves metabolism, energy pathways, cell growth and/or maintenance, transport and cell communication and signal transduction. We have performed immunohistochemistry for the validation of some of the novel candidates identified in our microarray studies.!Series_overall_design = Present study carried out mRNA expression profiling of five samples from patients diagnosed with tuberculous meningitis and four head injury cases were used as controls. We have used 4X44K arrays from agilent plaform. To validate our microarray results, we have done Immunohistochemistry on 15 TBM cases with control groups.
2011-07-01 | GSE23074 | GEO
Project description:Metagenomic water samples of Alicante city (Spain)