Abstract
BackgroundCalprotectin (CLP) is a promising biomarker for the evaluation of neutrophil-related inflammation. Our aim was to establish reference values for circulating CLP in different sample types and to study the effect of pre-analytical variables. MethodsReference values were determined in 100 healthy individuals. Pre-analytical variables were evaluated in 10 healthy controls and four rheumatoid arthritis patients with active disease and covered sample type (serum with/without gel separator, heparin, EDTA and citrate plasma), pre-centrifugation time (<2 h, 6 h, 24 h), storage condition (2–8 °C, 18–25 °C, 30 °C) and storage time (24 h, 72 h, 7 days). CLP measurements were performed with the EliA™Calprotectin 2 assay on Phadia™200 (Thermo Fisher Scientific). ResultsIn healthy controls, baseline CLP concentrations in serum were more than double the concentration in EDTA and citrate plasma (0.909 µg/mL versus 0.259 µg/mL and 0.261 µg/mL respectively). Heparin, EDTA and citrate stabilized CLP concentrations for up to 6 h before centrifugation, whereas significant increases in CLP levels were observed when serum was left untreated during that time period. ConclusionClinical studies on circulating CLP need to apply sample type-specific reference values and decision limits. To obtain reproducible CLP results in serum, more stringent pre-analytical sample handling instructions are needed.
Highlights
During the last decade, calprotectin (CLP) has gained widespread interest as biomarker of neutrophil-related inflammation and associated diseases
The coefficients of variation (CV) ranged from 5.3% to 10.8% for the patient pools and from 4.6% to 10.2% for the internal quality control material (iQC) samples provided by the manufacturer (Supplemental Table S2)
The CLP concentrations were signif icantly higher in serum-gel and lithium heparin plasma compared to EDTA and citrate plasma (Wilcoxon test; p < 0.0001)
Summary
Calprotectin (CLP) has gained widespread interest as biomarker of neutrophil-related inflammation and associated diseases. Calprotectin (CLP) is a promising biomarker for the evaluation of neutrophil-related inflammation. Our aim was to establish reference values for circulating CLP in different sample types and to study the effect of pre-analytical variables. Pre-analytical variables were evaluated in 10 healthy controls and four rheumatoid arthritis patients with active disease and covered sample type (serum with/without gel separator, heparin, EDTA and citrate plasma), pre-centrifugation time (
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
