Establishment and initial characterization of a simple 3D wound healing model

Abstract

Poor wound healing as consequence of malfunctions in the regulation of the healthy tissue repair response affects millions of people worldwide. The number of therapies available to successfully treat chronic wound is still very limited and their development is costly and time consuming. Therefore simple to use 3D systems, reflecting the in vivo tissue complexity, are urgently needed. We introduce a novel 3D organotypic model (OTC) containing the major cell components active during wound healing i.e. keratinocytes, fibroblasts and inflammatory cells that allows to determine the effects of different therapeutic approaches on wound closure, cell differentiation and cytokine secretion in chronic wounds. There are first reports on irradiation with visible light of different wave length (Low Level Light Therapy) as a means to enhance wound closure. However the mechanisms underlying this therapy as well as optimized irradiation wavelength and dose are not clear and were therefore analyzed using our 3D organotypic model. In the standardized OTC model we could demonstrate epithelial closure under control conditions as well as differential effects of red and blue light irradiation with respect to stability of the newly formed epithelium and time until epithelial closure. First results show differential cytokine profiles upon different wavelength irradiation e.g. high expression of TGF beta and IL-1 beta in red light irradiated cultures and increased GM-CSF expression in blue light irradiated and control cultures.