Effect of Anticoagulants and Cell Separation Media as Preanalytical Determinants on Zymographic Analysis of Plasma Matrix Metalloproteinases

Blood sampling as critical preanalytical determinant to use circulating MMP and TIMP as surrogate markers for pathological processes

“…There is rising evidence that blood sampling and handling markedly determine the concentrations of circulating MMP and TIMP. [6][7][8][9][10][11][12] Thus, to interpret that data correctly and to avoid wrong expectations in future studies using these markers, we want to draw the attention of interested clinicians to these facts that were particularly discussed in analytical journals. [6][7][8]12 Although the pitfalls in the measurement of circulating growth factors and cytokines for diagnostic purposes have become generally accepted, 13 similar evidences for MMP and TIMP have been widely ignored.…”

“…Because platelets and leukocytes contain high concentrations of MMP-9 and TIMP-1, 15,16 the observed differences between plasma and serum are attributed to the different release of these analytes from blood cells during platelet activation or sampling process. 11,12 Thus, it can be assumed that serum MMP-9 and TIMP-1 as measured by Giannelli et al 5 are possible misleading markers, because they obviously reflect a high nonspecific background by the release from blood cells and are not in direct relationship to cancer. In addition, Giannelli et al 5 did not describe the time between venipuncture and centrifugation and whether they used tubes available commercially with or without clot activator for serum preparation.…”

“…The use of blood samples collected with sodium citrate was suggested recently as material of choice for measurement of MMP-9 and MMP-2 to optimize the diagnostic validity in peripheral blood. 11,12,17 So far, no such systematic studies for TIMP were carried out.…”

Gelatinase concentrations and zymographic profiles in human breast cancer: Matrix metalloproteinases circulating in plasma are better markers for the subclassification and early prediction of cancer: The coagulation/fibrinolysis pathways alter the release, activation and recovery of different gelatinases in serum

“…10 No question is of greater interest to the clinicians dealing with breast diseases than the differentiation of BC subtypes through the determination of biomolecular markers useful for BC diagnosis and prognosis. Although the identification of the best source between plasma and serum for surrogate biomarkers is a matter of strenuous efforts and debate, [11][12][13][14][15][16][17] the scientific interest in the measurement of MMP in plasma/serum continues to mount, enhancing their promising development as reliable biomarkers.…”

A strong note of caution in using matrix metalloproteinase‐1 and its inhibitor, TIMP‐1 in serum as biomarkers in systolic heart failure

“…Jordan et al [1] used serum instead of plasma for their measurements. In this respect, the misuse of serum as sample for determining circulating MMPs and TIMP-1 in peripheral blood was strongly criticized [3][4][5][6][7][8]. Moreover, Jordan et al [1] did not give any details of serum sampling procedure, neither the type of serum collection with or without using a clot activator nor the time intervals between venipuncture and centrifugation of samples were explained.…”