Plasma tissue inhibitor of metalloproteinases-1 as a biological marker? Pre-analytical considerations.

Author(s): Lomholt AF, Frederiksen CB, Christensen IJ, Brünner N, Nielsen HJ

Publication: Clin Chim Acta, 2007, Vol. 380, Page 128-32

PubMed ID: 17328880 PubMed Review Paper? No

Purpose of Paper

Conclusion of Paper

Studies

1. Study Purpose

   The purpose of this study was to determine the effects of tourniquet use during collection, precentrifugation whole blood storage temperature, centrifugation speed (2500 x g, 3000 x g or 3500 x g)  and temperature (room temperature or 4 degrees C), and cellular contamination on the levels of TIMP-1 in plasma. All plasma was frozen at -80 degrees C for at least 48 h prior to analysis.

   Summary of Findings:

   Centrifugation speed and the use of a tourniquet for 2 min as opposed to no tourniquet during collection had no effects on TIMP-1 levels. Contamination of plasma with the 5 mM of plasma closest to the buffy coat significantly increased TIMP-1 levels (p<0.0001), and TIMP-1 levels were significantly correlated with beta-thromboglobulin (beta-TG) levels in contaminated tubes (r=0.75) but not in uncontaminated tubes (r=0.06). There were no significant differences in TIMP-1 levels between the lower, middle, and upper thirds of supernatant plasma after centrifugation, provided that the lowest 5 mM near the buffy coat was not evaluated. Storing whole blood at room temperature prior to centrifugation, as opposed to on ice, resulted in significantly higher levels of TIMP-1 (p<0.0001), but centrifugation temperature had no significant effects on TIMP-1 levels.

   Biospecimens

   • Bodily Fluid - Blood
   • Bodily Fluid - Plasma

   Preservative Types

   • Frozen

   Diagnoses:

   • Not specified
   • Normal

   Platform:

   Analyte	Technology Platform
   Protein	ELISA
   Protein	Immunoassay

   Pre-analytical Factors:

   Classification	Pre-analytical Factor	Value(s)
   Biospecimen Acquisition	Method of fluid acquisition	Tourniquet times compared
   Biospecimen Aliquots and Components	Biospecimen components	Plasma from 5 mM and higher above buffy coat Plasma added from 5 mM closest to buffy coat Upper third of supernatant (plasma) Middle third of supernatant (plasma) Lower third of supernatant (plasma)
   Storage	Storage temperature	On ice Room temperature
   Biospecimen Aliquots and Components	Blood and blood products	Plasma Whole blood Multiple sampling positions examined
   Biospecimen Aliquots and Components	Centrifugation	Multiple speeds compared Multiple temperatures compared Centrifugation delays investigated

   View more