Stabilization of Cellular RNA in Blood During Storage at Room Temperature: A Comparison of Cell-Free RNA BCT® with K3EDTA Tubes

Abstract

BackgroundMessenger RNA (mRNA) expression levels in blood cells are important in disease diagnosis, prognosis and biomarker discovery research. Accurate measurements of intracellular mRNA levels in blood cells depend upon several pre-analytical factors, including delays in RNA extraction from blood after phlebotomy. Dramatic changes in mRNA expression levels caused by delays in blood sample processing may render such samples unsuitable for gene expression analysis.ObjectivesThis study was conducted to evaluate a blood collection tube, cell-free RNA-BCT® (RNA-BCT), for its ability to stabilize mRNA expression level in blood cells post-phlebotomy using indicator mRNAs in reverse transcription quantitative real-time PCR (RT-qPCR) assays.MethodsBlood samples from presumed healthy donors were drawn into both RNA-BCT and K3EDTA tubes and maintained at room temperature (18–22 °C). The samples were processed to obtain white blood cells (WBCs) at days 0, 1, 2 and 3. Total cellular RNA was extracted from WBCs and mRNA concentrations were quantified by RT-qPCR for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), c-fos, and p53 transcripts.ResultsWhile blood cells isolated from K3EDTA tubes showed significant changes in cellular mRNA concentrations for GAPDH, c-fos, and p53, these mRNAs concentrations were stable in blood drawn into RNA-BCT.ConclusionThe reagent in the RNA-BCT device stabilizes cellular mRNA concentrations for GAPDH, c-fos and p53 for at least three days at room temperature.

Reproducibility of Digital PCR Assays for Circulating Tumor DNA Analysis in Advanced Breast Cancer

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CTC-mRNA (AR-V7) Analysis from Blood Samples—Impact of Blood Collection Tube and Storage Time

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