The influence of the blood handling process on the measurement of circulating TGF-ß1
Author(s): Zhao L, Wang L, Ji W, Lei M, Yang W, Kong FM
Publication: Eur Cytokine Netw, 2012, Vol. 23, Page 1-6
PubMed ID: 22456089 PubMed Review Paper? No
Purpose of Paper
The purpose of this paper was to determine the effects of delayed centrifugation and centrifugation speed and duration on levels of transforming growth factor-beta 1 (TGF-beta 1) in K2EDTA plasma and serum.
Conclusion of Paper
TGF-beta 1 levels in plasma increased with increasing storage of whole blood at room temperature or on ice before centrifugation. When whole blood was stored at room temperature for 1 h before centrifugation, serum TGF-beta 1 levels were significantly higher than in plasma or than in serum from blood stored on ice for 4 h. Plasma from whole blood centrifuged at 1,200 x g for 10 min had higher levels of TGF-beta 1 than plasma from blood centrifuged at 2,500 x g for 30 min, but this difference was eliminated when the plasma centrifuged at 1,200 x g was centrifuged again at 10,000 x g for 15 min before analysis.
Studies
-
Study Purpose
The purpose of this study was to determine the effects of delayed centrifugation and centrifugation speed and duration on levels of TGF-beta 1 in K2EDTA plasma and serum. Plasma tubes were left at room temperature for 5 min, 30 min or 1 h or on ice for 5 min, 30 min, or 240 min before centrifugation. Serum tubes were left at room temperature for 1 h or on ice for 4 h before centrifugation. Unless otherwise specified, plasma and serum were centrifuged at 2,500 x g for 30 min at 4 degrees C. All plasma and serum was frozen at -80 degrees C before analysis. One plasma specimen was left on ice for 3 h before centrifugation at 1,200 x g for 10 min. The effect of a second centrifugation at 10,000 x g for 15 min after frozen storage was investigated using the specimen centrifuged at 1,200 x g.
Summary of Findings:
TGF-beta 1 levels in plasma increased with increasing room temperature delays prior to centrifugation of whole blood, and significant increases, compared to no delay, were observed after 30 min and 1 h at room temperature (p=0.040 and p=0.001, respectively). When whole blood was stored on ice for 4 h prior to centrifugation, plasma levels of TGF-beta 1 were higher than when blood was centrifuged immediately (p=0.017). When whole blood was stored at room temperature for 1 h before centrifugation, serum TGF-beta 1 levels were significantly higher than in plasma from blood stored at room temperature for 1 h (p<0.001) or in serum from blood stored on ice for 4 h (p<0.001). Plasma from whole blood centrifuged at 1,200 x g for 10 min had higher levels of TGF-beta 1 than plasma from blood centrifuged at 2,500 x g for 30 min (p=0.003), but this difference was eliminated when the plasma centrifuged at 1,200 x g was centrifuged a second time at 10,000 x g for 15 min before analysis.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Protein ELISA Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Storage Storage duration 0 min
5 min
30 min
1 h
3 h
4 h
Storage Storage temperature Room temperature
On ice
Biospecimen Aliquots and Components Blood and blood products Plasma
Serum
Biospecimen Aliquots and Components Centrifugation Multiple durations compared
Multiple speeds compared
Different number of centrifugation steps compared
Centrifugation delays investigated