Development of a 3D skin tissue model using a 3D bioprinter and comparative evaluation of the expression levels of genes related to wound healing

Analyzing changes in gene expression levels during the complex process of wound healing is crucial for understanding the underlying mechanisms and evaluating wound treatment. In recent years, the development of in vitro skin models using 3D bioprinting technologies has emerged as a significant alternative to in vivo approaches. However, further studies are needed to assess how well the data obtained from these techniques can replace those from in vivo studies in terms of gene expression changes. In this study, we investigated how well skin wound models developed using 3D bioprinting technology can mimic the gene expression levels used as a benchmark in in vivo studies. To achieve this, a two-layered skin model was first created using 3D bioprinting, and samples were collected on days 0, 3, 7, and 10 following the creation of a scratch model to observe the healing process. The expression levels of 7 critical genes (KRT6A, KRT16, KRT17, KRT1, KRT10, COL1A1, and IL-6), which are known to exhibit varying expression levels during different stages of wound healing, were evaluated using real-time polymerase chain reaction (qPCR). The data obtained were also compared with in vivo and in vitro studies on wound healing available in the literature. Our histological findings confirmed the successful formation of the 3D skin model, and our molecular findings revealed that the expression levels of the relevant genes varied across different days of the wound healing process. The literature comparison indicated that the 3D skin wound model largely aligns with in vivo animal models. However, considering that the study is limited to a single wound model, we hope that increasing the number of related studies evaluating different wound models will reduce dependence on animal models, leading to the development of more ethical and effective in vitro models.