Longitudinal profiling of the whole blood transcriptional response of human volunteers to repeated malaria challenge
Ontology highlight
ABSTRACT: We took a systems immunology approach to analyse the evolution of the human immune response to the first three infections of life in a re-challenge model of falciparum malaria. Ten volunteers were infected up to three times with Plasmodium falciparum in 4- to 8-month intervals. Remarkably, parasite densities and the dynamics of blood-stage infection were not altered over the course of three homologous infections. To track the development of immunity in real-time we used whole blood RNA-sequencing to analyse each volunteer’s transcriptional response throughout infection and convalescence (up to 9 time points per volunteer per infection).
Project description:The diversity of human immune responses to P. falciparum is unknown and yet immune decision-making likely dictates outcome of infection We infected 15 malaria-naïve human volunteers with P. falciparum and used longitudinal whole blood transcriptional profiling to independently analyse the immune response in every volunteer
Project description:Gene expression data from whole-blood collected from Kenyan children with Plasmodium falciparum malaria infection at acute hospital admission (n=15) and at convalescence (n=9). A clinical history design type is where the organisms clinical history of diagnosis, treatments, e.g. vaccinations, surgery etc. Disease State: with Plasmodium falciparum malaria infection at acute hospital admission and at convalescence clinical_history_design
Project description:Gene expression data from whole-blood collected from Kenyan children with Plasmodium falciparum malaria infection at acute hospital admission (n=15) and at convalescence (n=9). A clinical history design type is where the organisms clinical history of diagnosis, treatments, e.g. vaccinations, surgery etc. Disease State: with Plasmodium falciparum malaria infection at acute hospital admission and at convalescence
Project description:Sixteen volunteers, that were age, gender and BMI matched, were included in the study. Blood samples were taken one per each volunteer on three different days to also assess variability of gene expression markers in one individual. In all datasets variability between volunteers was higher than variability of measurables in samples collected from the same volunteer on different days. We have identified genes in individuals that are highly stable during one month period and are thus suitable as markers of individual disease/therapy progress. A list of genes with low overall variability is also available. Interestingly, data show that important components of immune response are down-regulated with BMI in T helper and NK cells. This paper also gives the first insight into the gene expression profile of T helper and NK cells in healthy population.
Project description:Sixteen volunteers, that were age, gender and BMI matched, were included in the study. Blood samples were taken one per each volunteer on three different days to also assess variability of gene expression markers in one individual. In all datasets variability between volunteers was higher than variability of measurables in samples collected from the same volunteer on different days. We have identified genes in individuals that are highly stable during one month period and are thus suitable as markers of individual disease/therapy progress. A list of genes with low overall variability is also available. Interestingly, data show that important components of immune response are down-regulated with BMI in T helper and NK cells. This paper also gives the first insight into the gene expression profile of T helper and NK cells in healthy population. CD4 and NK lymphocytes were isolated with positive selection using magnetic nanoparticle based kits from StemCell Inc. (Canada) and frozen to -80°C until total RNA extraction.
Project description:Background: Malaria is a public health problem in parts of Thailand, where Plasmodium falciparum and Plasmodium vivax are the main causes of infection. In the northwestern border province of Tak parasite prevalence is now estimated to be less than 1% by microscopy. Nonetheless, microscopy is insensitive at low-level parasitaemia. The objective of this study was to assess the current epidemiology of falciparum and vivax malaria in Tak using molecular methods to detect exposure to and infection with parasites; in particular, the prevalence of asymptomatic infections and infections with submicroscopic parasite levels. Methods: Three-hundred microlitres of whole blood from finger-prick were collected into capillary tubes from residents of a sentinel village and from patients at a malaria clinic. Pelleted cellular fractions were screened by quantitative PCR to determine parasite prevalence, while plasma was probed on a protein microarray displaying hundreds of P. falciparum and P. vivax proteins to obtain antibody response profiles in those individuals. Results: Of 219 samples from the village, qPCR detected 25 (11.4%) Plasmodium sp. infections, of which 92% were asymptomatic and 100% were submicroscopic. Of 61 samples from the clinic patients, 27 (44.3%) were positive by qPCR, of which 25.9% had submicroscopic parasite levels. Cryptic mixed infections, misdiagnosed as single-species infections by microscopy, were found in 7 (25.9%) malaria patients. All sample donors, parasitaemic and non-parasitaemic alike, had serological evidence of parasite exposure, with 100% seropositivity to at least 54 antigens. Antigens significantly associated with asymptomatic infections were P. falciparum MSP2, DnaJ protein, putative E1E2 ATPase, and three others.
Project description:Malaria is spread by the transmission of sexual stage parasites, called gametocytes. However, with Plasmodium falciparum, gametocytes can only be detected in peripheral blood when they are mature and transmissible to a mosquito, which complicates control efforts. Here, we identify the set of genes overexpressed in patient blood samples with high levels of gametocyte-committed ring stage parasites. Expression of all 18 genes was regulated by transcription factor AP2-G, which is required for gametocytogenesis. We selected three genes, not expressed in mature gametocytes, to develop as biomarkers. All three biomarkers were validated in vitro using 6 different parasite lines and an algorithm developed that predicted gametocyte production in ex vivo samples and volunteer infection studies. The biomarkers were also sensitive enough to monitor gametocyte production in asymptomatic P. falciparum carriers allowing early detection and treatment of infectious reservoirs, as well as the in vivo analysis of factors that modulate sexual conversion.
Project description:Global, genomic responses of erythrocytes to infectious agents have been difficult to measure, because these cells are e-nucleated. We have previously demonstrated that in vitro matured, nucleated erythroblast cells at the orthochromatic stage can be efficiently infected by the human malaria parasite Plasmodium falciparum. We now show that infection of orthochromatic cells induces change in 609 host genes. 592 of these transcripts are up-regulated and associated with metabolic and chaperone pathways unique to P. falciparum infection, as well as a wide range of signaling pathways that are also induced in related apicomplexan infections of mouse hepatocytes or human fibroblast cells. Our data additionally show that polychromatophilic cells, which precede the orthochromatic stage and are not infected when co-cultured with P. falciparum, up-regulate a small set of 35 genes, 9 of which are associated with pathways of hematopoiesis and/or erythroid cell development. These data unexpectedly predict that blood stage P. falciparum may induce host responses common to infections of other pathogens. Further P. falciparum may modulate gene expression in bystander erythroblasts and thus influence pathways of erythrocyte development. Human primary erythroid cells were differentiated from CD34+ hematopoietic stem cells isolated from growth factor-mobilized peripheral blood (ALL Cells, Inc.). Cells from five donors were cultured until polychromatophilic and orthochromatophilic stages of differentiation and served as uninfected control samples. Of the five donors, three were used to initiate Plasmodium falciparum (3D7) infection at a multiplicity of infection = 5. Infected cells were harvested 24 hours post-infection, and RNA was isolated with Trizol (Invitrogen) and purified with RNeasy columns (QIAGEN) according to manufacturer recommendations. Microarray labeling and hybridizations were done according to Affymetrix protocols using HG U133 plus 2.0 chips. For GenePattern analysis, all samples (5 control and 3 infected samples) were analyzed; for Dchip analysis, only three samples were analyzed (the same 3 donors served as control and infected samples).
Project description:Influenza virus infection leads to global cardiac proteome remodeling during convalescence MTD project_description "Influenza virus infections lead to more than 500,000 hospitalizations in the U.S. every year. Patients with cardiovascular diseases have been shown to be at high risk of influenza mediated cardiac complications. Importantly, recent reports have provided clinical data supporting a direct link between laboratory-confirmed influenza virus infection and adverse cardiac events. However, the molecular mechanisms of how influenza virus infection induces detrimental cardiac changes, even after resolution of the pulmonary infection, is completely unknown.
Project description:Influenza virus infection leads to global cardiac proteome remodeling during convalescence MTD project_description "Influenza virus infections lead to more than 500,000 hospitalizations in the U.S. every year. Patients with cardiovascular diseases have been shown to be at high risk of influenza mediated cardiac complications. Importantly, recent reports have provided clinical data supporting a direct link between laboratory-confirmed influenza virus infection and adverse cardiac events. However, the molecular mechanisms of how influenza virus infection induces detrimental cardiac changes, even after resolution of the pulmonary infection, is completely unknown. We performed global quantitative proteomics as well as phosphoproteomics in this study.