Clinical evaluation of the levels of 12 cytokines in serum/plasma under various storage conditions using evidence biochip arrays.
Author(s): Guo GH, Dong J, Yuan XH, Dong ZN, Tian YP
Publication: Mol Med Rep, 2013, Vol. 7, Page 775-80
PubMed ID: 23291902 PubMed Review Paper? No
Purpose of Paper
The purpose of this paper was to determine the effects of collection tube type, freeze-thaw cycling and refrigerated storage on the levels of 12 cytokines in serum and plasma.
Conclusion of Paper
Plasma levels of interleukin (IL)-8, vascular endothelial growth factor (VEGF), and epidermal growth factor (EGF) were lower and more stable than serum levels. Serum collected in gel tubes had comparable levels of cytokines to serum collected in plain glass tubes. IL-1β, IL-4 and IL-10 increased after a single freeze-thaw cycle, but additional freeze-thaw cycles had no further effects on these 3 analytes or on any of the 9 other cytokines investigated. Storage of separated serum in gel tubes or plain glass tubes had no effect on cytokine levels. IL-8, EGF, tumor necrosis factor alpha (TNFα) and VEGF were affected by refrigerated storage of whole blood or separated serum in gel tubes and/or refrigerated storage of plasma in lithium heparin tubes.
Studies
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Study Purpose
The purpose of this study was to determine the effects of collection tube type, freeze-thaw cycling and refrigerated storage on the levels of 12 cytokines in serum and plasma. Blood from 9 healthy patients was centrifuged within 30 min and plasma or serum were removed immediately. For freeze-thaw cycles specimens were frozen at -80 degrees C and thawed at room temperature for 2 h at room temperature.
Summary of Findings:
Plasma levels of IL-8, VEGF, and EGF were lower (p<0.01) and more stable than serum levels. Serum collected in gel tubes had comparable levels of cytokines to serum collected in plain glass tubes. IL-1β, IL-4 and IL-10 increased 3-5 fold when specimen were freeze-thaw cycled compared to fresh specimens, but there was no effect of further freeze-thaw cycling or on any of the 9 other cytokines. Storage of separated serum in gel tubes or plain glass tubes had no effect on the levels of any of the cytokines. When unseparated serum in gel tubes was stored at 4 degrees after 3 or more days IL-8 increased, after 4 or more days EGF increased and after 6 days TNFα decreased. When unseparated serum was stored in glass tubes, higher levels of EGF from 6 h and IL-8 and TNF-α from 3 days were observed. When separated plasma was stored in lithium heparin tubes, EGF levels were elevated after 2 days. When unseparated plasma was refrigerated, levels of EGF increased within 6 h, VEGF increased after 1 day, and IL-8 and TNFα increased after 2 days.
Biospecimens
Preservative Types
- Frozen
- None (Fresh)
- Other Preservative
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Protein Clinical chemistry/auto analyzer Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Storage Freeze/thaw cycling 0 cycles
1 cycle
2 cycles
3 cycles
4 cycles
5 cycles
6 cycles
7 cycles
8 cycles
9 cycles
10 cycles
Biospecimen Acquisition Type of collection container/solution Lithium heparin tube
Glass tube
Gel tube
Biospecimen Aliquots and Components Blood and blood products Plasma
Serum
Whole blood
Storage Storage duration 0 h
6 h
1 day
2 day
3 days
4 days
5 days
6 days
Storage Type of storage container Lithium heparin tube
Gel tube
Plain glass tube
Biospecimen Preservation Type of fixation/preservation None (fresh)
Frozen
Refrigeration
Biospecimen Aliquots and Components Centrifugation Centrifugation delays investigated