Project description:In this study, whole blood samples were used to determine the gene expression of febrile culture confirmed enteric fever cases (ST = S. Typhi; SPT = S. Paratyphi), febrile culture negative individuals presenting to hospital in Kathamandu (sEF = suspected enteric fever), and healthy community controls (CTRL).
Project description:Viral infections are among the most common causes for fever without an apparent source (FWS) in young children; however, many febrile children are treated with antibiotics despite the absence of bacterial infection. Adenovirus, human herpesvirus 6 (HHV-6) and enterovirus are detected in children with FWS more often than other viral species. Virus and bacteria interact with pattern recognition receptors in circulating blood leukocytes and trigger specific host transcriptional programs that mediate immune response, and unique transcriptional signatures may be ascertained to discriminate between viral and bacterial causes for children with FWS. Microarray analyses were conducted on peripheral blood samples obtained from 51 pediatric patients with confirmed adenovirus, human herpesvirus 6 (HHV-6), enterovirus or bacterial infection. Whole blood transcriptional profiles could clearly distinguish febrile children from healthy controls, and febrile children with viral infections from afebrile children carrying the same virus. Molecular pathways regulating host immune response were the most affected in febrile children with infection. Pattern recognition programs were prominently activated in all febrile children with infection, while differential activation of transcriptional programs was observed among viral species. Interferon signaling pathway was uniquely activated in children with febrile viral infection, while a different set of pathways was uniquely activated in children with bacterial infection. Transcriptional signatures were identified and classified febrile children with viral or bacterial infection with 87% overall accuracy, an improvement from the current clinical practice of deducing from white blood cell (WBC) count status. Similar degree of accuracy was observed when we validated the signature probes on data sets from an independent study with different microarray platforms. The current study confirms the clinical utility of blood transcriptional analysis, suggests the composition of transcriptional signatures which can be used to ascertain the infectious etiology of febrile young children without an apparent source, thus limit the overuse of antibiotics on febrile children presenting with this common clinical complaint.
Project description:Viral infections are among the most common causes for fever without an apparent source (FWS) in young children; however, many febrile children are treated with antibiotics despite the absence of bacterial infection. Adenovirus, human herpesvirus 6 (HHV-6) and enterovirus are detected in children with FWS more often than other viral species. Virus and bacteria interact with pattern recognition receptors in circulating blood leukocytes and trigger specific host transcriptional programs that mediate immune response, and unique transcriptional signatures may be ascertained to discriminate between viral and bacterial causes for children with FWS. Microarray analyses were conducted on peripheral blood samples obtained from 51 pediatric patients with confirmed adenovirus, human herpesvirus 6 (HHV-6), enterovirus or bacterial infection. Whole blood transcriptional profiles could clearly distinguish febrile children from healthy controls, and febrile children with viral infections from afebrile children carrying the same virus. Molecular pathways regulating host immune response were the most affected in febrile children with infection. Pattern recognition programs were prominently activated in all febrile children with infection, while differential activation of transcriptional programs was observed among viral species. Interferon signaling pathway was uniquely activated in children with febrile viral infection, while a different set of pathways was uniquely activated in children with bacterial infection. Transcriptional signatures were identified and classified febrile children with viral or bacterial infection with 87% overall accuracy, an improvement from the current clinical practice of deducing from white blood cell (WBC) count status. Similar degree of accuracy was observed when we validated the signature probes on data sets from an independent study with different microarray platforms. The current study confirms the clinical utility of blood transcriptional analysis, suggests the composition of transcriptional signatures which can be used to ascertain the infectious etiology of febrile young children without an apparent source, thus limit the overuse of antibiotics on febrile children presenting with this common clinical complaint. Total RNA samples extracted from whole blood of young children were processed for hybridization onto Illumina Human-HT12 version 4 beadchips, and differential expression of the transcripts was analyzed between sick children with either viral or bacterial infection and healthy children.
Project description:Cumulative malaria parasite exposure in endemic regions often results in the acquisition of partial immunity and asymptomatic infections. However, there is limited information on how host-parasite interactions mediate maintenance of chronic symptomless infections that sustain malaria transmission. In this study, we identified uninfected and asymptomatic individuals and followed them until they manifested with symptoms of fever in the presence of malaria parasites and compared the gene expression profiles of peripheral blood mononuclear cells (PBMCs). The host response of asymptomatic children was characterized by downregulation of genes associated with inflammatory responses, compared to uninfected children and children with febrile malaria. They did show greater expression of some genes associated with the humoral response compared to uninfected children. Interestingly, the host responses during febrile infections that followed an asymptomatic infection featured stronger inflammatory responses, whereas the febrile host responses from previously uninfected children featured increased humoral immune responses.
Project description:RNA sequencing data were generated from the whole blood of children with a range of acute febrile illnesses. These data were used as the validation cohort for a multiclass diagnostic gene expression signature for the discrimination of 18 infectious and inflammatory diseases which was discovered using publicly available microarray datasets.
Project description:Cumulative malaria parasite exposure in endemic regions often results in the acquisition of partial immunity and asymptomatic infections. There is limited information on how host-parasite interactions mediate maintenance of chronic symptomless infections that sustain malaria transmission. Here, we have determined the gene expression profiles of the parasite population and the corresponding host peripheral blood mononuclear cells (PBMCs) from 21 children (<15 years). We compared children who were defined as uninfected, asymptomatic and those with febrile malaria. Children with asymptomatic infections had a parasite transcriptional profile characterized by a bias toward trophozoite stage (~12 hours-post invasion) parasites and low parasite levels, while earlier ring stage parasites were characteristic of febrile malaria. The host response of asymptomatic children was characterized by downregulated transcription of genes associated with inflammatory responses, compared with children with febrile malaria, which may lead to less cytoadherence of more mature parasite stages. Interestingly, the host responses during febrile infections that followed an asymptomatic infection featured stronger inflammatory responses, whereas the febrile host responses from previously uninfected children featured increased humoral immune responses. The priming effect of prior asymptomatic infection may explain the blunted acquisition of antibody responses seen to malaria antigens following natural exposure or vaccination in malaria endemic areas.
Project description:Whole blood transcriptional profiles of patients with (1) active pulmonary ['AdjuVIT active TB' and 'New active pulmonary'] and (2) extrapulmonary TB ['New active-extrapulmonary'] at time of diagnosis, (3) long-term recovery after treatment for active pulmonary TB ['AdjuVIT active TB'], (4) febrile illnesses presenting to hospital ['Fever mixed infection'] and (5) febrile pneumonia ['Fever pneumonia'] before antibiotic treatment, and (6) healthy vounteers. Each array sample represents a separate individual in each group. This submission includes two human whole genome Agilent Array Designs: A-MEXP-2104 and A-AGIL-28. Each of the individual raw array files are included as well as a single processed file representing the data matrix of all the merged and normalised data for the probes that are shared by the two array designs.
Project description:Febrile patients PCR positive for H1N1 swine flu, seasonal H1N1 and seasonal H3N2 in nasal swabs and controls consisting of febrile patients with rhinovirus infection or febrile patients of non-viral etiology (nasal swabs PCR negative for common respiratory viruses and blood PCR negative for dengue and parvovirus B19) were assessed consecutively for global transcriptional changes in whole blood
Project description:Febrile patients PCR positive for H1N1 swine flu, seasonal H1N1 and seasonal H3N2 in nasal swabs and controls consisting of febrile patients with rhinovirus infection or febrile patients of non-viral etiology (nasal swabs PCR negative for common respiratory viruses and blood PCR negative for dengue and parvovirus B19) were assessed consecutively for global transcriptional changes in whole blood Peripheral whole blood collected in PAX-gene tubes and extracted for total RNA
Project description:Febrile seizures are the most prevalent type of seizures among children up to 5 years of age (2-4% of Western-European children). Complex febrile seizures are associated with an increased risk to develop temporal lobe epilepsy. To investigate short- and long-term effects of experimental febrile seizures (eFS), we induced eFS in highly febrile convulsion-susceptible C57BL/6J mice at post-natal day 10 by exposure to hyperthermia (HT) and compared them to normotherm-exposed (NT) mice. We detected structural re-organization in the hippocampus 14 days after eFS. To identify molecular candidates, which entrain this structural re-organization, we investigated temporal changes in mRNA expression profiles eFS 1 hour to 56 days after eFS. We identified 931 regulated genes and profiled several candidates using in situ hybridization and histology at 3 and 14 days after eFS. This is the first study to report genome-wide transcriptome analysis after eFS in mice. We identify temporal regulation of multiple processes, such as stress-, immune- and inflammatory responses, glia activation, glutamate-glutamine cycle and myelination. Identification of the short- and long-term changes after eFS is important to elucidate the mechanisms contributing to epileptogenesis.