Effects of sample handling on the stability of interleukin 6, tumour necrosis factor-alpha and leptin.
Author(s): Flower L, Ahuja RH, Humphries SE, Mohamed-Ali V
Publication: Cytokine, 2000, Vol. 12, Page 1712-6
PubMed ID: 11052823 PubMed Review Paper? No
Purpose of Paper
Conclusion of Paper
Studies
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Study Purpose
The purpose of this study was to determine if blood specimen storage at 4 degrees C pre- and post-separation impacts quantifiable levels of IL-6, TNFalpha, and leptin.
Summary of Findings:
Cytokine levels in blood specimens that underwent immediate separation by centrifugation were not significantly affected by storage at 4 degrees C for up to 6 hours. In non-separated blood specimens stored at 4 degrees C IL-6 and TNFalpha levels differed significantly in from 0 hour controls after 4 hours, with levels decreasing and increasing, respectively.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Protein ELISA Protein Radioimmunoassay Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Storage Storage duration 0 h
1 h
2 h
4 h
6 h
Biospecimen Aliquots and Components Centrifugation Centrifugation delays investigated
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Study Purpose
The purpose of this study was to determine if the type of anticoagulant used impacts detectable IL-6, TNFalpha, and leptin levels.
Summary of Findings:
In reference to serum and EDTA-plasma specimens, which produced comparable results for all proteins of interest, lithium heparin and sodium citrate treated specimens yielded lower levels of IL-6 and TNFalpha. While highly variable, leptin levels did not differ significantly among anticoagulants.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Protein ELISA Protein Radioimmunoassay Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Acquisition Anticoagulant EDTA
Lithium heparin
Sodium citrate
None
Biospecimen Aliquots and Components Blood and blood products Serum
Plasma
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Study Purpose
The purpose of this study was to determine if multiple freeze-thaw cycles impact detectable levels of IL-6, TNFalpha, and leptin in plasma specimens.
Summary of Findings:
TNFalpha levels significantly and progressively increased after 3 freeze-thaw cycles. IL-6 and leptin levels remained stable for up to 6 cycles.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Protein ELISA Protein Radioimmunoassay Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Storage Freeze/thaw cycling 1 cycle
2 cycles
3 cycles
4 cycles
5 cycles
6 cycles
Biospecimen Acquisition Anticoagulant EDTA
Lithium heparin
Sodium citrate