Background: This study aimed to evaluate an effect of the time period between drawing the peripheral blood and specimen processing on the stability of mRNA levels of 7 selected genes.
Methods: Blood samples derived from 15 healthy volunteers were always processed at five consecutive time points 0.5, 1.5, 2, 3, and 9 hours; mRNA was quantified by real-time PCR.
Results: Anti-inflammatory genes CCL2 and IL10 showed a significant rise of expression between the 3rd and 9th hour after blood collection (p ≤ 0.5). Significant decrease of mRNA levels in relation to time lag was observed for TLR4 and MYC genes (p ≤ 0.5). Interestingly, the initial two hours after drawing the blood revealed a high interindividual variability in cellular response to stress connected with blood drawing and ex vivo post-sampling condition.
Conclusions: These results point out the need for a strict standardization of handling the blood specimen with regards to peripheral blood sample processing time between phlebotomy and RNA isolation.