The effect of tropical temperatures on the quality of RNA extracted from stabilized whole blood samples

Background: Whole-blood derived transcriptional profiling is widely used in biomarker discovery, immunological research and therapeutic development. Traditional molecular and high-throughput transcriptomic platforms, including molecular assays with quantitative-PCR (qPCR) and RNA-sequencing (RNA-seq), are dependent upon high-quality, high-quantity and intact RNA. However, collecting high-quality RNA from field studies can be challenging in remote tropical locations due to resource restrictions and logistics of post-collection processing. The current study tested the relative performance of two most widely used whole blood RNA collection systems, PAXgene® and Tempus™, in optimal laboratory conditions as well as suboptimal conditions in tropical field sites, including the effects of extended storage times and high storage temperatures. Results We found that Tempus™ tubes maintained a slightly higher RNA quantity and integrity relative to PAXgene® tubes at suboptimal tropical conditions. Both PAXgene® and Tempus™ tubes gave similar RNA purity (A260/A280). Additionally, we found that Tempus™ tubes preferentially maintained the stability of mRNA transcripts even as RNA quality decreased with storage length and temperature. Conclusions Our results suggest that Tempus™ blood RNA collection tubes are preferable to PAXgene® for whole-blood collection in suboptimal tropical conditions for RNA-based studies in resource-limited settings.