Assessment of sample collection and storage methods for multicenter immunologic research in children.

Multicenter studies involving both large and small centers separated by significant distances pose unique challenges to biological sample collection. The objective of this study was to evaluate protocols for determining inflammatory biomarkers that are cost and manpower efficient for handling blood destined for a sample repository. Tempus (Applied Biosystems) and Paxgene (Qiagen) blood collection systems were evaluated for RNA isolation. P100 tubes (BD), containing propriety stabilizers for preservation of plasma proteins, were evaluated for protein content and compared with plasma collected in conventional tubes. Blood for plasma separation was spiked with recombinant TNF-alpha and IL-2 prior to being processed and stored under various conditions. The Tempus RNA system produced a significantly greater yield of RNA at comparable quality when stored at 4 degrees C and shipped at ambient temperature than any other condition tested. The Tempus system was 20% less expensive and required approximately 40% less processing time thereby reducing costs. The P100 system preserved recombinant TNF-alpha in blood shipped at ambient temperature significantly better than conventionally collected plasma that was shipped on dry ice. There was no significant difference in IL-2 levels between the two collection methods and shipping temperatures. The Tempus RNA blood collection tubes and the P100 protein stabilization system provide the opportunity for reliable collection and ambient temperature transport of samples in multicenter studies. This cost-effective, standardized protocol for a large multicenter trial ensures the integrity of biological samples and maximizes study participation by both large and small centers.