TY - JOUR
T1 - Tumor Necrosis Factor-Alpha and Receptor Activator of Nuclear Factor-κB Ligand Augment Human Macrophage Foam-Cell Destruction of Extracellular Matrix Through Protease-Mediated Processes
AU - Skjøt-Arkil, Helene
AU - Barascuk, Natasha
AU - Larsen, Lise Korsager
AU - Dziegiel, Morten
AU - Henriksen, Kim
AU - Karsdal, Morten A
PY - 2012/2/1
Y1 - 2012/2/1
N2 - By secreting proteases such as cathepsins and matrix metalloproteinases (MMPs), macrophage foam cells may be a major cause of ruptured atherosclerotic plaques. The aims of the present study were to investigate in vitro role of human macrophage foam cells in degrading type I collagen, a major component of extracellular matrix (ECM) in plaques, and to establish whether the pro-inflammatory molecules, tumor necrosis factor (TNF)-alpha, and receptor activator of nuclear factor-κB ligand (RANK-L) increase this degradation. CD14+ monocytes isolated from peripheral blood were differentiated into macrophage foam cells and cultured on a type I collagen matrix in the presence of TNF-alpha and RANK-L. Matrix degradation was measured by the cathepsin K-generated C-terminal cross-linked telopeptide of type I collagen (CTX-I) and the MMP-generated carboxyterminal telopeptide of type I collagen (ICTP) in supernatants showing that macrophage foam cells secrete MMPs and cathepsin K, resulting in release of ICTP and CTX-I. Stimulation with TNF-alpha increased CTX-I and ICTP dose dependently, with ICTP levels increasing by 59% and CTX-I levels increasing by 43%. RANK-L enhanced the release of CTX-I and ICTP by 56% and 72%, respectively. This is, to our knowledge, the first data describing a simple in vitro system in which macrophage foam cells degradation of matrix proteins can be monitored. This degradation can be enhanced by cytokines since TNF-alpha and RANK-L significantly increased the matrix degradation. This in vitro system in part is a model system for the macrophage-mediated proteolytic degradation of the ECM, which is found in many diseases with an inflammatory component.
AB - By secreting proteases such as cathepsins and matrix metalloproteinases (MMPs), macrophage foam cells may be a major cause of ruptured atherosclerotic plaques. The aims of the present study were to investigate in vitro role of human macrophage foam cells in degrading type I collagen, a major component of extracellular matrix (ECM) in plaques, and to establish whether the pro-inflammatory molecules, tumor necrosis factor (TNF)-alpha, and receptor activator of nuclear factor-κB ligand (RANK-L) increase this degradation. CD14+ monocytes isolated from peripheral blood were differentiated into macrophage foam cells and cultured on a type I collagen matrix in the presence of TNF-alpha and RANK-L. Matrix degradation was measured by the cathepsin K-generated C-terminal cross-linked telopeptide of type I collagen (CTX-I) and the MMP-generated carboxyterminal telopeptide of type I collagen (ICTP) in supernatants showing that macrophage foam cells secrete MMPs and cathepsin K, resulting in release of ICTP and CTX-I. Stimulation with TNF-alpha increased CTX-I and ICTP dose dependently, with ICTP levels increasing by 59% and CTX-I levels increasing by 43%. RANK-L enhanced the release of CTX-I and ICTP by 56% and 72%, respectively. This is, to our knowledge, the first data describing a simple in vitro system in which macrophage foam cells degradation of matrix proteins can be monitored. This degradation can be enhanced by cytokines since TNF-alpha and RANK-L significantly increased the matrix degradation. This in vitro system in part is a model system for the macrophage-mediated proteolytic degradation of the ECM, which is found in many diseases with an inflammatory component.
U2 - 10.1089/adt.2010.0366
DO - 10.1089/adt.2010.0366
M3 - Journal article
C2 - 22053710
SN - 1540-658X
VL - 10
SP - 69
EP - 77
JO - Assay and Drug Development Technologies
JF - Assay and Drug Development Technologies
IS - 1
ER -
