Staphylococcus aureus has emerged as a significant pathogen causing severe, invasive disease in otherwise healthy people. Despite considerable advances in understanding the epidemiology, resistance mechanisms, and virulence factors produced by the bacteria, there is limited knowledge of the in vivo host immune response to acute, invasive S. aureus infections. Herein, we report that peripheral blood mononuclear cells from patients with severe S. aureus infections demonstrate a distinctive and robust gene expression profile which is validated in a distinct group of patients and on a different microarray platform. Application of a systems-wide modular analysis framework reveals significant over-expression of innate immunity genes and under-expression of genes related to adaptive immunity. Simultaneous flow cytometry analyses demonstrated marked alterations in immune cell numbers, with decreased central memory CD4 and CD8 T cells and increased number of monocytes. CD14+ monocyte numbers significantly correlated with the gene expression levels of genes related to the innate immune response. These results demonstrate the value of applying a systems biology approach that reveals the significant alterations in the components of circulating blood lymphocytes and monocytes in invasive S. aureus infections.
Enhanced monocyte response and decreased central memory T cells in children with invasive Staphylococcus aureus infections.
Sex, Treatment, Race
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines.
Specimen part, Subject, Time
View SamplesWhile dendritic cells (DCs) are known to play a major role in the process of vaccination, the mechanisms by which vaccines induce protective immunity in humans remain elusive. Herein, we used gene microarrays to characterize the transcriptional programs induced over time in human monocyte-derived DCs (moDCs) in vitro in response to influenza H1N1 Brisbane, Salmonella enterica and Staphylococcus aureus. We built a data-driven modular analytical framework focused on 204 pathogen-induced gene clusters. The expression of these modules was analyzed in response to 16 well-defined ligands, targeting TLRs, cytoplasmic PAMP receptors and cytokine receptors. This multi-dimensional framework covers the major biological functions of APC, including the IFN response, inflammation, DC maturation, T cell activation, antigen processing, cell motility and histone regulation. This framework was used to characterize the response of monocytes and moDCs to 14 commercially available vaccines. These vaccines displayed quantitatively and qualitatively distinct modular signatures in monocytes and DCs, in particular Fluzone and Pneumovax, highlighting the functional and phenotypic differences between APC subsets. This modular framework allows the application of systems immunology approaches to study early transcriptional changes in human APC subsets in response to pathogens and vaccines, which might guide the development of improved vaccines.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines.
Specimen part, Subject, Time
View SamplesWhile dendritic cells (DCs) are known to play a major role in the process of vaccination, the mechanisms by which vaccines induce protective immunity in humans remain elusive. Herein, we used gene microarrays to characterize the transcriptional programs induced over time in human monocyte-derived DCs (moDCs) in vitro in response to influenza H1N1 Brisbane, Salmonella enterica and Staphylococcus aureus. We built a data-driven modular analytical framework focused on 204 pathogen-induced gene clusters. The expression of these modules was analyzed in response to 16 well-defined ligands, targeting TLRs, cytoplasmic PAMP receptors and cytokine receptors. This multi-dimensional framework covers the major biological functions of APC, including the IFN response, inflammation, DC maturation, T cell activation, antigen processing, cell motility and histone regulation. This framework was used to characterize the response of monocytes and moDCs to 14 commercially available vaccines. These vaccines displayed quantitatively and qualitatively distinct modular signatures in monocytes and DCs, in particular Fluzone and Pneumovax, highlighting the functional and phenotypic differences between APC subsets. This modular framework allows the application of systems immunology approaches to study early transcriptional changes in human APC subsets in response to pathogens and vaccines, which might guide the development of improved vaccines.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines.
Specimen part, Subject, Time
View SamplesThe mechanisms by which vaccines interact with human APCs remain elusive. We applied systems biology to define the transcriptional programs induced in human DCs by pathogens, innate receptor ligands and vaccines. Upon exposing DCs to influenza, Salmonella enterica and Staphylococcus aureus, we built a modular framework containing 204 pathogen-induced transcript clusters. Module fingerprints were then analyzed in DCs activated with 16 innate receptor ligands. This framework was then used to characterize human monocytes, IL-4 DC and blood DC subsets responses to 13 vaccines. Different vaccines induced distinct signatures based on pathogen type, adjuvant formulation and APC targeted. Fluzone broadly activated IL-4 DC whereas pneumovax only activated monocytes and gardasil (HPV) only activated CD1c+ mDC. This highlights that different antigen-presenting cells respond to different vaccines. Finally, the blood signatures from individuals vaccinated with fluzone or infected with influenza were interpreted using these modules. We identified a signature of adaptive immunity activation following vaccination and symptomatic infections, but not asymptomatic infections. These data, offered with a web interface, might guide the development of improved vaccines.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines.
Subject, Time
View SamplesWhile dendritic cells (DCs) are known to play a major role in the process of vaccination, the mechanisms by which vaccines induce protective immunity in humans remain elusive. Herein, we used gene microarrays to characterize the transcriptional programs induced over time in human monocyte-derived DCs (moDCs) in vitro in response to influenza H1N1 Brisbane, Salmonella enterica and Staphylococcus aureus. We built a data-driven modular analytical framework focused on 204 pathogen-induced gene clusters. The expression of these modules was analyzed in response to 16 well-defined ligands, targeting TLRs, cytoplasmic PAMP receptors and cytokine receptors. This multi-dimensional framework covers the major biological functions of APC, including the IFN response, inflammation, DC maturation, T cell activation, antigen processing, cell motility and histone regulation. This framework was used to characterize the response of monocytes and moDCs to 14 commercially available vaccines. These vaccines displayed quantitatively and qualitatively distinct modular signatures in monocytes and DCs, in particular Fluzone and Pneumovax, highlighting the functional and phenotypic differences between APC subsets. This modular framework allows the application of systems immunology approaches to study early transcriptional changes in human APC subsets in response to pathogens and vaccines, which might guide the development of improved vaccines.
Transcriptional specialization of human dendritic cell subsets in response to microbial vaccines.
Specimen part, Subject, Time
View SamplesThis series regroups different datasets (training set, test set, validation set, longitudinal set, separated cell set) to identify and characterise a specific transcriptional signature for patients with active TB, distinct from patients with latent TB and healthy controls. The training set dataset was used to identify a whole blood transcriptional signature for active TB patients in London, across a range of ethnicity. This signature was then validated in an independent cohort of patients, also recruited in London (the test set), and then further confirmed in an additional independent cohort recruited in Cape Town, South Africa (validation set), in order to confirm that the defined signature was present in both high (Cape Town, South Africa) and medium incidence regions (London, UK). The longitudinal dataset was then used to explore how successful TB treatment modifies this transcriptional signature. The separated cell set compares the transcriptional profiles in purified cell subsets (neutrophils, monocytes and T cells) to assess which cell types are contributing to the whole blood signature, and in what way. These studies may ultimately help to improve the diagnosis of active tuberculosis which normally relies on culture of the bacilli, which can take up to 6 weeks, and sometimes the bacilli cannot be obtained from sputum thus requiring invasive techniques such as bronchoalveolar lavage (BAL). In some cases (30%) the bacill cannot be grown from sputum or BAL. Any diagnostic tool would need to be valid across a range of ethnicities, and be valid in both high and low incidence countries. A further aim was to determine whether latent TB patients have a distinct homogeneous or heterogeneous signature, since it is not currently possible to determine using present tests (Tuberculin skin test - TST - or MTb antigen responsiveness of blood cells to produce IFN-gamma - IGRA assay) whether the mycobacteria have been cleared, are still present but are controlled by an active immune response, or to predict which patients will develop active TB. Defining heterogeneity in the latent TB patients would be an important step in developing diagnostics which could detect those most at risk of developing active TB, and thus enable targeted preventive therapy. The latter situation may be determined if Latent patients have a blood transcriptional signature similar to that in Active patients. The transcriptional signature in whole blood and cell subsets from Active TB patients may also provide information as to the factors leading to immunopathogenesis, thus possibly identifying therapeutic targets. The transcriptional profile in latent TB may give information regarding protective factors controlling the infection, important for vaccine development. Finally, definition of a transcriptional signature which responds to therapy could facilitate the development of surrogate biomarkers for drug or vaccine studies.
An interferon-inducible neutrophil-driven blood transcriptional signature in human tuberculosis.
Sex, Age, Race
View SamplesTuberculosis (TB), caused by infection with Mycobacterium tuberculosis (M. tuberculosis), is a major cause of morbidity and mortality worldwide and efforts to control TB are hampered by difficulties with diagnosis, prevention and treatment. Most people infected with M. tuberculosis remain asymptomatic, termed latent TB, with a 10% lifetime risk of developing active TB disease, but current tests cannot identify which individuals will develop disease. The immune response to M. tuberculosis is complex and incompletely characterized, hindering development of new diagnostics, therapies and vaccines. The goals of this study include: 1. Identify a transcript signature for active TB in intermediate and high burden settings, correlating with radiological extent of disease and reverting to that of healthy controls following treatment; 2. Identify a specific transcript signature that discriminated active TB from other inflammatory and infectious diseases; 3. Classify TB signature using modular and pathway analysis tools.
An interferon-inducible neutrophil-driven blood transcriptional signature in human tuberculosis.
Sex, Age, Race
View SamplesThis dataset aims to validate and confirm the signature identified in the training set. The aim of the experiment was to define transcriptional signatures in whole blood of TB patients (before drug treatment) and healthy controls to distinguish the signature of Latent and Active TB patients from each other and from healthy controls. This will help in diagnosis of active tuberculosis which normally relies on culture of the bacilli, which can take up to 6 wks, and sometimes the bacilli cannot be obtained from sputum thus requiring invasive techniques obtaining bronchoalveolar lavage (BAL). In some cases the bacill cannot be grown from sputum or BAL. Secondly the aim was to determine whether Latent patients have a homogeneous or heterogeneous signature, one may expect the latter since it is not possible to determine by the present tests (Tuberculin skin test - TST - or MTb antigen responsiveness of blood cells to produce IFN-gamma - IGRA assay) whether the mycobacteria has been cleared, is still present but is controlled, or if patients are recently infected or reactivated and will develop active TB.
An interferon-inducible neutrophil-driven blood transcriptional signature in human tuberculosis.
Sex, Age, Race
View SamplesThe aim of this study was to compare the transcriptional response to TB in regions of different incidence / prevalence.
An interferon-inducible neutrophil-driven blood transcriptional signature in human tuberculosis.
Sex, Age, Race
View Samples