Project description:We have reported the change from overall gene expression to specific genes and pathways involved in the immune cells of blood depending on the storage and handling conditions. The overall gene pattern showed a strong correlation and the prediction of immune cell proportion was conserved under 4℃ refrigeration for up to 48 hours regardless of the RNA extraction kits used. However, after 4 days of refrigeration, the correlation started to decrease. Additionally, the expression of 65 genes increased more than two-fold while the expression of 221 genes decreased less than two-fold within 48 hours of refrigeration. Our data would contribute to the experimental design of basic research and minimizing the bias of the blood RNA-seq results, since the need for RNA-seq continually increases but it it hard to perform blood RNA-seq immediately after every blood collection.
Project description:Circulating microRNAs (miRNAs) from blood are increasingly recognized as biomarker candidates for human diseases. Clinical routine settings frequently include blood sampling in tubes with EDTA as anticoagulant without considering the influence of phlebotomy on the overall miRNA expression pattern. We collected blood samples from six healthy individuals each in an EDTA blood collection tube. Subsequently, the blood was transferred into PAXgeneTM tubes at three different time points, i.e. directly (0 min), 10 min, and 2 h after phlebotomy. As control blood was also directly collected in PAXgeneTM blood RNA tubes that contain a reagent to directly lyse blood cells and stabilize their content. For all six blood donors at the four conditions (24 samples) we analyzed the abundance of 1,205 miRNAs by human Agilent miRNA V16 microarrays.
Project description:Circulating microRNAs (miRNAs) from blood are increasingly recognized as biomarker candidates for human diseases. Clinical routine settings frequently include blood sampling in tubes with EDTA as anticoagulant without considering the influence of phlebotomy on the overall miRNA expression pattern. We collected blood samples from six healthy individuals each in an EDTA blood collection tube. Subsequently, the blood was transferred into PAXgeneTM tubes at three different time points, i.e. directly (0 min), 10 min, and 2 h after phlebotomy. As control blood was also directly collected in PAXgeneTM blood RNA tubes that contain a reagent to directly lyse blood cells and stabilize their content. For all six blood donors at the four conditions (24 samples) we analyzed the abundance of 1,205 miRNAs by human Agilent miRNA V16 microarrays. Blood from 6 healthy individuals was collected in one PAXgeneTM blood RNA tube (Becton Dickinson, 2.5 ml blood) and one dipotassium EDTA blood tube (EDTA-KE Monovette, Sarstedt, 9 ml blood) per individual. There was no known disease for any of the blood donors. A fixed volume of 2.5 ml blood from the EDTA tube was transferred at three different time points after blood withdrawal (0 min, 10 min, and 2 h) into fresh PAXgene blood RNA tubes to ensure stabilization of the RNA in the blood samples. All PAXgene blood tubes were stored at room temperature until at least 2 h after the last transfer of EDTA blood into PAXgene tubes, to ensure complete lysis of the blood cells, before they were stored at -20°C until RNA isolation.
Project description:Recombinant human erythropoietin administration studies involving transcriptomic approaches have demonstrated a gene-expression signature that could aid detection of blood doping. However, current anti-doping testing does not involve blood collection into tubes with RNA preservative. This study investigated if whole blood in long-term storage and whole blood leftover from standard haematological testing in short-term storage could be used for transcriptomic analysis despite lacking RNA preservative. Whole blood samples were collected from thirteen and fourteen healthy males, for long-term and short-term storage experiments. Long-term storage: whole blood collected into Tempus™ tubes and K2EDTA tubes and subjected to long-term (i.e., −80°C) storage and RNA extracted. After storage, K2EDTA tubes were thawed and extracted using GeneJET RNA Purification Kit (Thermo Fisher Scientific, Vilnius, Lithuania) or Tempus™ Spin RNA Isolation Kit (Life Technologies, Carlsbad, CA, USA). RNA quality and purity was sufficient for gene expression analysis. Principle Component Analysis of microarray and RNA-seq gene expression data for long-term storage: When comparing gene expression between blood tubes with and without RNA preservation, 6% (4058 transcripts) were differentially expressed. RNA quantity, purity and integrity was not significantly compromised from long-term storage in blood storage tubes lacking RNA preservative, indicating that transcriptomic analysis could be conducted using anti-doping samples collected or biobanked without RNA preservation.
Project description:To determine differential gene expression in peripheral blood of asthmatic individuals undergoing allergen inhalation challenge, post-challenge compared to pre-challenge Blood was collected immediately prior to, and two hours after challenge The 8 PAXgene non-globin reduced (PAX.NGR) samples were combined with 10 EDTA samples (n=9) for one analysis (PAX.NGR+EDTA) comparing gene expression in whole blood between pre and post challenge using the following covariates: tube type, sex, age, PC20 at pre-challenge, and FEV1 after onset and 2h post challenge and the RNA integrity number. Preprocessing and filtering were applied to the PAX.NGR+EDTA dataset using the Factor Analysis for Robust MicroArray Summarization (farms) package in R The Linear Models for MicroArrays (limma) package was used to determine differential gene expression using a Benjamini Hochberg FDR of 5%.
Project description:Purpose: Recombinant human erythropoietin administration studies involving “omics” approaches have demonstrated a gene-expression signature that could aid detection of blood doping. However, current anti-doping testing does not involve blood collection into tubes with RNA preservative. This study investigated if whole blood in long-term storage could be used for transcriptomic analysis despite lacking RNA preservation. Methods: Whole blood samples were collected from thirteen male healthy individuals. Long-term storage: whole blood collected into Tempus™ tubes and K2EDTA tubes and subjected to long-term (i.e., −80°C) storage and RNA extracted. After storage, Tempus and K2EDTA tubes were thawed and extracted using Tempus™ Spin RNA Isolation Kit (Life Technologies, Carlsbad, CA, USA). Samples from seven subjects that presented higher RIN value (≥7) were selected for RNA_Seq analysis. Results: The experiment provided RNA quality and purity for gene expression analysis. Total of 19239 genes were mapped and the gene expression analysis showed that 658 genes were differentially expressed (which means 3.4% of mapped genes). With 269 being up-regulated and 389 down-regulated. None of the transcripts described in previous studies as biomarkers for blood doping (Durussel et al. 2016; Wang, Durussel, et al. 2017) were differently expressed. Conclusion: RNA quantity, purity and integrity was not significantly compromised from long-term storage in blood storage tubes lacking RNA stabilisation, indicating that transcriptomic/omics analysis could be conducted using anti-doping samples collected or biobanked without RNA preservation.
Project description:Purpose: Recombinant human erythropoietin administration studies involving “omics” approaches have demonstrated a gene-expression signature that could aid detection of blood doping. However, current anti-doping testing does not involve blood collection into tubes with RNA preservative. This study investigated if whole blood in short-term storage could be used for transcriptomic analysis despite lacking RNA preservation. Methods: Whole blood samples were collected from fourteen male healthy individuals. Short-term storage: whole blood collected into K2EDTA tubes and subjected to short-term (i.e., at 4°C) storage for 6 hours, 12 hours, 24 hours and 48 hours. After storage, blood from K2EDTA tubes were transferred into Tempus™ Blood tubes, and then extracted using Tempus™ Spin RNA Isolation Kit (Life Technologies, Carlsbad, CA, USA). Samples from four subjects of each time point that presented higher RIN value (≥7) were selected for RNA_Seq analysis. Results: The experiment provided RNA quality and purity for gene expression analysis. Considering 6-hours storage as a reference group, the number of differentially expressed genes were 19, 45 and 70 in comparison to 12, 24 and 48-hours, respectively (which means 0.37, 0.88 and 1.37% of mapped genes). Of the 19 differentially expressed genes in the comparison 6 vs. 12-hours, 9 overlapped with the 45 in the comparison 12 vs. 24-hours. Furthermore, 40 of those 45 overlapped with the 70 differentially expressed in the comparison 6 vs. 48-hours. None of the transcripts described in previous studies (Durussel et al. 2016; Wang, Durussel, et al. 2017) were differently expressed. Conclusion: RNA quantity, purity and integrity was not significantly compromised from short-term storage in blood storage tubes lacking RNA stabilisation, indicating that transcriptomic/omics analysis could be conducted using anti-doping samples collected without RNA preservation.
Project description:DNA and RNA samples from blood are the common examination target for non-invasive physical tests and/or biomedical studies. Since high-quality DNA and RNA samples guarantee the correctness of these tests and/or studies, we investigated the effects of storage temperature and storage duration of whole blood on DNA and RNA qualities. Subjects were enrolled to donate blood samples which were stored for different durations and at different temperatures, followed by the examinations on RNA quality, qPCR, DNA quality and DNA methylation. For RNA, we observed obvious quality decline with storage duration longer than 24 hours. Storage at low temperature does not keep RNA samples from degradation. And, storing whole blood samples in freezer dramatically damage RNA. For DNA, quality decline was not observed even with storage duration for 15 days. However, DNA methylation significantly altered with storage duration longer than three days. Storage duration within 24 hours is critical for collecting high-quality RNA samples for next-generation sequencing (NGS) assays (RIN≧8). If microarray assays are expected (RIN≧7), storage duration within 32 hours is acceptable. Although DNA is resistant within 15 days when kept in whole blood, DNA quantity dramatically decreases owing to WBC lysis. In addition, duration for more than three days significantly alter DNA methylation status, globally and locally. Our result provides a reference for dealing with blood samples.
Project description:Mature human red blood cells (RBCs) are terminally differentiated anuclear cells. While initially thought to lack any nucleic acids, human RBCs are found to contain abundant and diverse species of RNA transcripts with functional relevance. Given the absence of novel transcription, RBCs may provide an interesting cellular context to study RNA metabolism over time. One clinically relevant context is the ex vivo storage of RBCs in blood banks for use in blood transfusion. Some studies have indicated that the transfusion of “old” or aged stored RBCs may be associated with adverse outcomes due to various storage changes termed “storage lesions”. However, other studies do not support these effects, and much remains unknown about the relevant changes associated with RBC storage. Here, we employed the NanoString nCounter assay for global miRNA profiling to comprehensively define the miRNA turnover during ex vivo RBC storage. This profiling demonstrates that the abundance of most RBC miRNAs did not change significantly during the 42 days of refrigerated storage, indicating extremely long decay half-lives. Unexpectedly, miR-720, a cleavage product of tRNAThr, increased dramatically in the first two weeks and persisted during storage. Furthermore, we present evidence for a role of angiogenin in tRNA cleavage to generate miR-720 during RBC storage. The dramatic increase in miR-720 may serve as a new characteristic for storage lesion and may be used to monitor transfused RBCs in clinical patients and athletes performing blood doping.
Project description:Short sleep duration is associated with adverse metabolic, cardiovascular, and inflammatory effects. Co-twin study methodologies account for familial (e.g., genetics and shared environmental) confounding, allowing assessment of subtle environmental effects, such as the effect of short habitual sleep duration on gene expression. Therefore, we sought to investigate gene expression in monozygotic twins discordant for actigraphically phenotyped habitual sleep duration. Eleven healthy monozygotic twin pairs (82% female; mean age 42.7 years; SD=18.1), selected based on subjective sleep duration discordance, were objectively phenotyped for habitual sleep duration with two-weeks of wrist actigraphy. Peripheral blood leukocyte (PBL) RNA from fasting blood samples was obtained on the final day of actigraphic measurement and hybridized to Illumina humanHT-12 microarrays. Differential gene expression was determined between paired samples and mapped to functional categories using Gene Ontology. Next, a more comprehensive gene set enrichment analysis was performed based on the entire PBL transcriptome. The mean 24 hour sleep duration of the total sample was 439.2 minutes (SD=46.8 minutes; range 325.4 to 521.6 minutes). Mean within-pair sleep duration difference per 24 hours was 64.4 minutes (SD=21.2; range 45.9 to 114.6 minutes). The twin cohort displayed distinctive pathway enrichment based on sleep duration differences. Short sleep was associated with up-regulation of genes involved in transcription, ribosome, translation and oxidative phosphorylation. Unexpectedly, genes down-regulated in short sleep twins were highly enriched in immuno-inflammatory pathways such interleukin signaling and leukocyte activation, as well as developmental programs, coagulation cascade, and cell adhesion. Objectively assessed habitual sleep duration in monozygotic twin pairs appears to be associated with distinct patterns of differential gene expression and pathway enrichment. By accounting for familial confounding and measuring real life sleep duration, our study shows the transcriptomic effects of short sleep on dysregulated immune response and provides a potential link between sleep deprivation and adverse metabolic, cardiovascular and inflammatory outcomes.