The Effect of Preanalytical Conditions on Blood-Based Inflammation Biomarkers

Blood-based inflammation biomarkers have potential for
diagnostic,
prognostic, and predictive testing, but preanalytical processing conditions
can affect biomarker levels. We investigated how needle-to-freezer
time, centrifugation timing, and tube types influence inflammation
biomarkers. Twenty subjects donated 21 different blood samples in
collection tubes, including plasma and serum types. Ninety-two biomarkers
from each sample were analyzed using the Olink Target 96 Inflammation
panel. We compared biomarker concentrations across different preanalytical
variables to a reference standard tube. Intraclass, Pearson, and Spearman’s
correlation coefficients were calculated. We also assessed the impact
of these conditions on age-related associations with biomarkers. Across
the preprocessing protocol/blood matrix combinations, 38%–83%,
50%–87%, and 47%–79% of proteins showed good to excellent
correlations in intraclass, Pearson, and Spearman analyses, respectively.
Eighteen proteins differed by >0.5 NPX units between test and reference
protocols. Among 30 comparisons of age-related biomarker associations
showing p ≤ 0.05 at baseline, 12 (40%) maintained
a p ≤ 0.05 across all needle-to-freezer times.
Many proteins in the Olink Target 96 Inflammation panel exhibited
robust stability across various preanalytical conditions, indicating
that blood-based inflammation biomarkers are suitable for testing
across different blood specimen types. Further studies are needed
to evaluate the impact of long-term storage.