Abstract
This study investigated the behavior of macrophages in the wound healing process in human skin using a new artificial skin model with macrophages. The experimental group (the artificial skin model with human monocytes) and control group 1 (without monocytes) were irradiated with a CO2 laser and compared with control group 2 (no laser irradiation with monocytes). Tissue samples were collected for 7 days after laser irradiation, and the degree of tissue damage and the process of regeneration were evaluated using hematoxylin-eosin and immunohistochemical staining. The monocytes changed to macrophages in the samples. The number of macrophages increased and their size was larger after laser irradiation in the experimental group from the day 3 and reached a peak on the day 5. The macrophages were activated both in the irradiated area and in the whole sample. MCP-1, a chemokine produced by inflammatory reactions, was identified in the epidermal layer from the keratinocytes and the dermal epidermal border region. These results suggest that MCP-1 from macrophages induces an acceleration of the re-epithelization in the epidermis, while also inducing wound healing. In conclusion, this new artificial skin model with macrophages demonstrated increased tissue interactions, especially in inflammatory reactions.
