Levels of plasma matrix metalloproteinases (MMP-2 and MMP-9) in response to INTEGRA® dermal regeneration template implantation

Background: Cutaneous wound healing results in scar formation. Matrix metalloproteinases (MMP) transform extracellular matrix proteins and modulate inflammation and cell signaling, thus determining scar outcome. To provide rapid wound closure and reduced scarring, dermal scaffolds were introduced. Little is known about the influence of these materials on MMPs levels. Material/Methods: In this in vivo study the levels of MMP-2, MMP-9, and mediators of inflammation and fibrosis (IL-4 and TGF-beta 1) in patients treated with Integra (R) dermal regeneration template (IDRT) were investigated. In the group of 11 pediatric patients treated with IDRT, levels of selected molecules were analyzed before surgery and at day 1, 7, and 25 after scaffold implantation. Results: The mean IDRT take rate was 89.5 +/- 4.7% with 4 patients (36%) who developed local infection. Patients were divided into 2 groups according to presence of infection (1 group with complications and 1 group without complications). In the group with complications, the IDRT take rate was significantly reduced compared to the group without complications (71.5 +/- 5.4 vs. 100 +/- 0.1; p<0.005). Plasma levels of MMP-2 were significantly (p<0.05) elevated in both groups on day 7 after the scaffold placement compared to baseline. Positive correlations between IL-4 and MMP-2 (p=0.01) in the group with complications and TGF-beta 1 and MMP-9 (p=0.012) in both groups were observed. Conclusions: These findings suggest that Integra (R) scaffold degradation is mainly caused by MMP-2, whereas inflammation associated with local infection increases levels of this molecule and it is not associated with elevation of MMP-9. This shows that dermal regeneration with Integra (R) uses molecular mechanisms other than scar formation during dermal wound healing.