A novel collagen gel-based measurement technique for quantitation of cell contraction force

Abstract

ResearchCite this article: Jin T, Li L, Siow RCM, Liu K-K. 2015 A novel collagen gel-based measurement technique for quantitation of cell contraction force. J. R. Soc. Cell contraction force plays an important role in wound healing, inflammation, angiogenesis and metastasis. This study describes a novel method to quantify single cell contraction force in vitro using human aortic adventitial fibroblasts embedded in a collagen gel. The technique is based on a depth sensing nano-indentation tester to measure the thickness and elasticity of collagen gels containing stimulated fibroblasts and a microscopy imaging system to estimate the gel area. In parallel, a simple theoretical model has been developed to calculate cell contraction force based on the measured parameters. Histamine (100 mM) was used to stimulate fibroblast contraction while the myosin light chain kinase inhibitor ML-7 (25 mM) was used to inhibit cell contraction. The collagen matrix used in the model provides a physiological environment for fibroblast contraction studies. Measurement of changes in collagen gel elasticity and thickness arising from histamine treatments provides a novel convenient technique to measure cell contraction force within a collagen matrix. This study demonstrates that histamine can elicit a significant increase in contraction force of fibroblasts embedded in collagen, while the Young's modulus of the gel decreases due to the gel degradation.

Spatial distributions of pericellular stiffness in natural extracellular matrices are dependent on cell-mediated proteolysis and contractility

“…Jin et al computed cell contractile forces in 3D ECMs by monitoring the contraction of a type I collagen gel seeded with human aortic adventitial fibroblasts. They estimated the average cell contractile force was approximately 1.5 nN, which is well within our range of estimated forces[45]. Bloom et al tracked displacements of 3.6 μm diameter beads around HT-1080 cells in a type I collagen gel.…”

Predictable fibroblast tension generation by measuring compaction of anchored collagen matrices using microscopy and optical coherence tomography

“…However, the shape measurements, including heights of anchored matrices and areas of released matrices, could only provide qualitative information about the relative mechanical tension generated in the matrix. Although the mechanical tension in other collagen matrix systems has been quantified or controlled through supporting posts or rings [27,43,44], little has been done to quantify and monitor the mechanical tension in the anchored collagen matrix [45]. For that to occur, one would need measure not only the area contraction (deformation) of released matrices, but also the mechanical properties (linear/nonlinear elasticity or viscoelasticity) of developing collagen matrices, as regulated by mechanics of any materials.…”

Integration of growth factor gene delivery with collagen‐triggered wound repair cascades using collagen‐mimetic peptides

“…After allowing an additional 24 hr for a gradient in PDGF‐BB expression to form, 5,000 fresh NIH/3T3 cells (labeled with CellTracker TM Deep Red) were plated onto each gel. These cells were prelabeled with the CellTracker TM Deep Red dye via the manufacturer's protocol to enable rapid tracking of cell migration, and the cells were plated at a low density (∼6,250 cells/cm 2 ) to minimize the effects of cell‐induced contraction . A 75% reduction in cell seeding densities lessened contraction in collagen gel height from approximately 16 to 5% over 48 hr (data not shown) and migration was monitored using a Leica DMI6000 B inverted microscope (Wetzlar, Germany).…”