Wound healing is composed of 3 processes: formation of the epithelium, deposition of the connective tissue and contraction.
The contraction process could be mediated by specialized fibroblasts called myofibroblasts. Three-dimensional collagen gels have been widely used to study fibroblast contraction, integrin signaling, cell apoptosis and cytoskeletal reorganization, which may be more biologically relevant than studies using two-dimensional systems.
We propose 2 different culture models to study the ability of fibroblasts to rearrange and contract in collagen matrices in vitro:
- The 2-step model combines an initial contraction period of the attached matrix leading to a mechanical load, followed by a release of the matrices, resulting in additional mechanical unloading and contraction as the mechanical stress dissipates.
- The contraction model in floating matrix. In this model, a freshly polymerized collagen matrix containing cells is released from the culture dish and left free in the culture medium. The contraction occurs in the absence of external mechanical load and without appearance of stress fibers in the cells.