Biomarkers of Inflammation for Population Research: Stability of C-Reactive Protein And Alpha1-Acid Glycoprotein in Dried Blood Spots

Eleanor Brindle, University of Washington
Masako Fujita, University of Washington
Bettina Shell-Duncan, University of Washington

Biomarkers of the acute-phase response (APR) to inflammation, including C-reactive protein (CRP) and alpha1-acid glycoprotein (AGP), are strongly associated with risk of morbidity and mortality from cardiovascular disease, stroke, diabetes, and other conditions, and are critical for interpreting biomarkers of micronutrient status, many of which are influenced by APR. CRP climbs sharply then quickly declines following injury or infection, while AGP begins to increase 24 hours or more after the initial insult, and remains elevated for up to one week. CRP and AGP can thus be complementary biomarkers of APR. CRP and AGP measurement in non-clinical, population-level research is simplified by the availability of affordable enzyme immunoassay methods, and dried blood spot (DBS), rather than serum, sample collection. However, DBS stability under field storage conditions has not been adequately examined. We compare CRP and AGP results in paired serum and DBS collected and stored under both laboratory and field conditions.