Heparin and EDTA anticoagulants differentially affect the plasma cytokine levels in humans

Cytokines and chemokines are the cell signaling proteins which are considered as important biomarkers of inflammation and immunity. However the fragile nature of these markers results in the concentration variation due to various external factors. We assessed the influence of commonly used anticoagulants (EDTA and heparin) on various cytokine levels from 32 paired plasma samples using highly sensitive multiple cytokine estimation assay. Out of 17 cytokines estimated, 15 were detectable in more than 80% of the samples from both the groups. TNF-alpha, IFN-gamma, IL-4, IL-5, and G-CSF levels were significantly higher (p values < 0.05 for all) in plasma with EDTA, whereas the levels of IL-6, IL-8, IL-10, IL-17, MIP-1 beta, GM-CSF and MCP-1 were found to be significantly higher (p values < 0.05 for all) in plasma with heparin. There was no significant difference in the levels of IL-7, IL-12 (P70) and IL-13 in both the groups. The study showed that the anticoagulants significantly affect the measurement of certain cytokines. Hence, it is important to choose an appropriate anticoagulant before the estimation of cytokines for reliable use of plasma cytokines as biomarkers in patient management.