Z Gastroenterol 2011; 49 - P2_50
DOI: 10.1055/s-0030-1269567

RNA stability in human liver: effects of different processing times, temperatures and storage methods

SML Lee 1, S Gashi 2, S Fröba 2, KW Jauch 3, WE Thasler 1
  • 1Zentrum für Leberzellforschung, Klinikum Großhadern, München
  • 2Gewebebank der Chirurgischen Klinik und Poliklinik-Großhadern im Auftrag der Stiftung Human Tissue and Cell Research HTCR, München
  • 3Chirurgische Klinik und Poliklinik Klinikum Großhadern, München

The Grosshadern Hospital Tissue Bank is a repository of clinically annotated surgical remnant tissues that can be accessed by researchers for basic and translational research. An important technology for elucidating molecular mechanisms of diseases is reverse transcription polymerase chain reaction (RT-PCR). However, accuracy of information garnered by RT-PCR is highly dependent on tissue quality. Thus, this study aimed to determine if tissues with longer processing times are suitable for RT-PCR studies and if processing temperatures or storage in RNAlater would help maintain RNA quality.

Liver samples were collected over a time course; during surgery before blood arrest, after surgery, post sampling by the pathology department (Tpp), 3 hours after Tpp and 1 day after Tpp. For the last 2 time-points, samples were kept at either room temperature (RT) or on ice after Tpp for the duration. All samples were then stored with or without RNAlater at -80°C. Subsequently, these tissues were assessed for RNA quality and relative expression levels of 5 genes.

RNA quality was only significantly decreased by 1.9-fold at 1 day after Tpp at RT with or without RNAlater (P <0.05). However, normalized relative gene expressions of HPRT, GUSB, MYC, HIF1and GFER were not significantly different when the various time-points were compared against each other (P >0.05). Also, there were generally no significant differences between samples stored with or without RNAlater (P >0.05).

In conclusion, it is recommended that samples be kept on ice during processing and that they be processed as quickly as possible for storage at -80°C. However, when longer processing times are inevitable, samples can still be used for RT-PCR studies, provided that relative expression of the gene of interest is proven not to be affected. Thus, this study shows that samples with longer processing times can still be banked and this relaxed criterion will increase accrual of samples to the tissue bank.

RNA stability - RT-PCR - gene expression - tissue bank