The Glasbox®: A New System for Measurement of Contractile Forces Developed by Fibroblasts in Collagen Lattices

• Published in: Wound repair and regeneration Vol. 13; no. 1; p. A23
• Main Authors: Viennet, C, Armbruster, V, Gharbi, T, Humbert, P
• Format: Journal Article
• Language: English
• Published: Oxford, UK; Malden, USA Blackwell Science Inc 01.01.2005
• ISSN: 1067-1927; 1524-475X
• DOI: 10.1111/j.1067-1927.2005.130117z.x

Cellular contraction, defined as the force cells exhibit on the extracellular matrix, plays a significant role in dermal tissue. To study the contractility of cells in vitro, we have developed a new patented device named GlaSbox®“Growing Lattice Study Box”. It consists of a cell chamber composed with 8 rectangular wells (26 × 33 mM) in which lattices develop. Two opposite silicon beams hang down into each well. The lattice is attached to this sensor through a grid directly etched on the lower part of the beams. A strain gauge is deposited at the beam surface, and connected to form a Wheastone bridge. The strain gauges signal output is amplified then converted and collected by a computer which includes an acquisition card and a specific program giving directly the forces in real time. The significant advantages of the GlaSbox® are: –  the absence of any interface between the collagen lattice and the beams which maintain it stretched, –  its ability to test eight lattices simultaneously, –  the low volumes of cells and collagen required. To demonstrate the applicability of this system, contractile forces of human fibroblasts from different skin conditions were measured such as chronic venous leg ulcers and striae distensae. These fibroblasts were found to produce an average force of 1.10−8 N/cell and have greater contractile capacity than normal fibroblasts (Viennet et al., J Wound Care 2004, in press). The GlaSbox® is a useful tool to study the contractility of dermis equivalent composed of various fibroblast lines and, the effect of different active principles or even growth factors (e.g., TGF‐β) on cellular contraction. In addition, it can be used to examine the relationship between cellular contraction, cell proliferation, and collagen production, which is important for the understanding of the mechanism of scar tissue formation.