Figure 2. Hypothetical model for maturation into fully differentiated cell. Under healthy conditions, pre-existing healthy matrix recruits precursor cells that are close to final differentiation and permits their differentiation to occur. During inflammation and wound repair, undifferentiated "stem" cells, presumably separated by several stages from full differentiation, interact with growth factors (GF) and available matrix, differentiate to the next stage, and produce matrix. This cell interacts with the matrix, which contains the ECM produced by the previous stage cell, and differentiates to the next stage. This process continues until the cell becomes fully differentiated.