Bioengineered matrices--part 2: focal adhesion, integrins, and the fibroblast effect.

Initial efforts at biologic skin replacement strategies were mainly directed toward keratinocyte regeneration and epithelial replacement. It soon became evident that without a good dermal scaffold, the long-term efficacy of epithelial replacement was very limited. Further studies have focused on matrix replacement predominantly involving collagen frameworks with or without cellular additions. The fibroblast is central to the process of dermal regeneration and to the success of biologic matrix design. The sequence of cellular focal adhesion, integrin phosphorylated activation, intracellular and extracellular signaling, cytoskeletal activation, changes in cell morphology, and cytokine growth factor interaction are all important in influencing cell proliferation, cell spreading, neocollagenesis, and collagen translocation. A basic acellular matrix with chemical composition and correct physical structure (pore size and resistance) that takes cognizance of this sequence of matrix deposition and fibroblast functionality should be successful in promoting intrinsic healing and dermal replacement.