Dataset Information

The Extracellular RNA Quality Control (exRNAQC) study (phase 2)

ABSTRACT: The use of blood-based extracellular RNA (exRNA) as clinical biomarker requires the implementation of a validated procedure for sample collection, processing and profiling. So far, no study has systematically addressed the pre-analytical variables affecting transcriptome analysis of exRNAs. In the first phase of the exRNAQC study, we evaluated 10 blood collection tubes, 3 time points between blood draw and downstream processing, and 8 RNA purification methods using the supplier-specified minimum and maximum biofluid input volumes. The impact of these pre-analytics is assessed by deep transcriptome profiling of both small and messenger RNA from healthy donors' plasma or serum. In this second phase, we assessed interactions between blood collection tubes, time points and purification methods. More project info on bioRxiv (manuscript title: Performance of RNA purification kits and blood collection tubes in the Extracellular RNA Quality Control (exRNAQC) study) and https://oncornalab.ugent.be/project/exrnaqc/

PROVIDER: EGAS00001006499 | EGA |

REPOSITORIES: EGA

ACCESS DATA

Similar Datasets

Project description:The main aim of the study was to compare genome-wide gene expression profiles obtained from the two widely used commercially available whole blood RNA collection systems - PAXgeneTM and TempusTM tubes. Comparisons of present call rates, variances, correlations and influence of globin reduction across the two collection systems was performed using in vivo glucocorticoid stimulation in 24 peripheral blood samples from three individuals. Three healthy male volunteers aged 30-35 years with body mass index of 20-25 were enrolled in the study.1.5 mg dexamethasone stimulated peripheral blood samples were drawn 3 hours later. For each sample, duplicate measures of 2.5 ml and 3ml blood was collected in PAXgeneTM tubes (PreAnalytiX GmbH, Hombrechtikon, Switzerland) and TempusTM tubes (Applied Biosystems, Foster City, CA, USA) respectively. The PAXgeneTM and TempusTM tubes were stored for 2.5 hours at room temperature and then transferred to -20°C. Due to the lower RNA yield from the PAXgeneTM tubes, RNA from two PAXgeneTM tubes was pooled together for the experiment . Total RNA was isolated from whole blood stored in PAXgeneTM and TempusTM tubes according to the respective manufacturer's instructions. The PAXgeneTM samples were processed using the PAXgeneTM Blood RNA Kit based on the Quiagen method for column purification of nucleic acids (PreAnalytiX GmbH, Hombrechtikon, Switzerland, catalogue number 762174). The TempusTM samples were isolated using the TempusTM Spin RNA Isolation Kit (Applied Biosystems, Foster City, CA, USA, catalogue number 4380204). RNA quality was assessed using an Agilent 2100 Bioanalyzer (Agilent Technologies, Palo Alto, CA, USA). The concentration and purity of total RNA was independently assessed by 260/280 UV absorption ratios, respectively (Nanophotometer, Implen, Munich, Germany). RNA samples were divided into non-globin reduced and globin reduced groups. The GLOBINclearTM-Human Kit (Ambion, Inc., Texas, USA, catalogue number #AM1980) was used to remove globin mRNA. Sample amplification and labeling for both globin-reduced and non-reduced samples was performed using the IlluminaR TotalPrep RNA Amplification Kit (Ambion, Inc., Texas, USA, catalogue number AMIL1791).

Project description:Gene expression profiling using blood samples is a valuable tool for biomarker discovery in clinical studies. Different whole blood RNA collection and processing methods are highly variable and might confound comparisons of results across studies. The main aim of the study was to compare how blood storage, extraction methodologies, and the blood component itself may influence gene expression profiling where samples were collected in triplicate from five healthy donors. Whole blood was collected in RNAGard™, PAXgene™ as well as collection tubes with anticoagulant such as dipotassium ethylenediaminetetraacetic acid (K2EDTA) and acid citrate dextrose solution A (ACD-A). Peripheral blood mononuclear cells (PBMCs) were separated using sodium citrate cell preparation tubes (CPT), FICOLL™, immunomagnetic and Leukolock™ methods. The Leukolock™, K2EDTA and ACD-A blood tubes were shipped overnight using cold conditions and rest of the methods were immediately frozen with or without pre-processing. The RNA was isolated from whole blood and peripheral blood mononuclear cells (PBMCs) with a total of 10 different experimental conditions employing several widely utilized RNA isolation methods. The RNA quality as assessed by RNA integrity Number (RIN) showed that all PBMC procedures had the highest RIN values when processed and stabilized in TRIzol before RNA extraction. Initial data analysis showed that human blood stored at 4°C overnight performed equally well when compared to frozen stabilized blood. Comparisons within and across donor/method replicates showed signal to noise patterns which were not captured by RIN value alone. Our results provide some new insights into RNA isolation from blood samples, how the RNA isolation quality and apparent gene expression is influenced by the choice of storage, handling, and methodologies, and how careful consideration is necessary to avoid bias resulting from downstream processing. Better characterization of the effects of collection method idiosyncrasies will facilitate further research into understanding the effect of gene expression on variability in human sample types.

Dataset Information

The Extracellular RNA Quality Control (exRNAQC) study (phase 2)

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets