Sample preparation technique and white cell content influence the detectable levels of growth factors in platelet concentrates.
Author(s): Zimmermann R, Arnold D, Strasser E, Ringwald J, Schlegel A, Wiltfang J, Eckstein R
Publication: Vox Sang, 2003, Vol. 85, Page 283-9
PubMed ID: 14633254 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 the effects of PC collection and preparation methods on levels of TGF-beta 1, PDGF-AA, PDGF-AB. After 1 h at room temperature, PC was frozen at -70 degrees C (method 1), frozen at -70 degrees C for 30 min and stored at room temperature for 30 min before being refrozen (method 2), dissolved in a hypotonic 0.5% solution of Triton-X-100 in water and frozen at -70 degrees C (method 3) or mixed with a calcium-thrombin solution and left at room temperature for 1 h (method 4), 24 h (method 5), or 1 h at room temperature, 30 min at -70 degrees C and another 30 min at room temperature (method 6) before centrifugation and frozen storage at -70 degrees C.
Summary of Findings:
Plateletpheresis yielded a slightly higher concentration of platelets with much less white blood cell contamination than leukocytapheresis. The concentrations of all three growth factors were highest when PC was dissolved in Triton-X-100 prior to freezing (method 3). The next highest concentrations of PDGF-AA or -AB were obtained when PC was mixed with a calcium-thrombin solution and left for 1 h at room temperature (method 4), exposed to a second freeze-thaw cycle (method 2), or both (method 6), but increasing the incubation of PC with calcium-thrombin solution from 1 to 24 h slightly decreased PDGF-AA and PDGF-AB levels. In contrast to PDGF, mixing PC with a calcium-thrombin solution decreased TGF-beta 1 levels compared to PC that was not incubated with either calcium-thrombin or Triton-X-100, regardless of incubation length, and a second freeze-thaw cycle had little to no effect. While the trends in preparation method effects were similar for PC obtained by plateletpheresis and leukocytapheresis, the amount of growth factor per platelet was not the same between methods.
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Cell count/volume Hematology/ auto analyzer Protein Immunoassay Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Storage Freeze/thaw cycling 1 cycle
2 cycles
Immunoassay Specific Targeted peptide/protein TGF-beta 1
PDGF-AA
PDGF-AB
Biospecimen Acquisition Method of fluid acquisition Leukocytapheresis
Plateletpheresis
Analyte Extraction and Purification Incubation duration/condition 1 h
24 h
With calcium-thrombin solution
With Triton-X 100 in water
Without calcium-thrombin or Triton-X 100