Alysa Edwards, University of Utah
Life Sciences
Percutaneous devices (PDs) constitute foreign materials that penetrate through the protective skin barrier to provide connection between internal and external environments. It has been previously shown that the periprosthetic tissue at the PD-skin interface is under a continuous state of wound healing, which often results in epidermal downgrowth. This continuous downgrowth is detrimental to the long-term survival of these devices. To date, there are no effective methodologies available to either prevent or quantify the degree of epidermal downgrowth indicating a need to find effective markers to document the healing response around these devices. In this study, periprosthetic tissues from a previous pig- back study were subjected to two different evaluations: (1) standard histology (HandE) and (2) immunohistochemical staining (IHC). Healing responses around PDs made with different material types were examined using cytokeratin 6 and collagen 4 to determine the degree of wound healing and granulation tissue maturity. Varying exposure time and concentration of stains, staining procedures were optimized. The interfacial tissues were then analyzed using either a photo or a confocal microscope. Preliminary data (Figure 1) indicated that there were noticeable differences in the periprosthetic regions between the material types used. The IHC data confirmed that the periprosthetic tissue is a hyper cellular region with a high density of blood vessels (collagen 4) and migrating keratinocytes. This data further confirmed the morphological differences observed between implant types using standard histology. Continued analysis will quantify the amount of collagen 4 within the periprosthetic tissue using imageJ software. Semi-quantitative data from each implant type will then be compared to predict biocompatibility. This research has demonstrated that IHC staining could be a potential tool for understanding the healing cascades around the percutaneous device.