Composite PEGDA Scaffolds for UV-Bioprinting of Decellularized Plant Cells

Abstract

Regenerative medicine for tissue repair is an important and intensive area of research. The ultimate goal of regenerative medicine is to repair or replace tissues in patients who have suffered from traumatic accidents or degenerative diseases, often by utilizing biomaterial scaffolds or matrices to direct or stimulate cell growth. There are numerous approaches to producing 3D matrices that support the growth of mammalian cells. One method of creating a biomaterial scaffold is through the use of decellularized plant cells. Decellularization is the process of removing all the cells from plant tissue, leaving behind a cellulosic scaffold that involves cellulose, hemicellulose, pectin and lignin. The Pelling lab has previously demonstrated that natural plant-derived cellulose scaffolds can be produced by employing common decellularization approaches, which support 3D cell culture. Here, we focus on bringing together plant decellularization techniques with 3D bioprinting to create decellularized plant scaffolds with controllable architectures. More specifically, this project focuses on the decellularization of the BY-2 cell line, a Japanese line that originates from the tobacco plant. The resulting cellulose is then mixed with polyethylene glycol diacrylate (PEGDA), to create a biocompatible ink, which can be incorporated into the Lumen-X 3D bio-printer. Scaffolds are then custom printed, offering a versatility of possible scaffold shapes and pore sizes, making them suitable for different applications in tissue engineering. Additionally, our goal is to show that mammalian cells can successfully attach to and colonize these scaffolds. We specifically used NIH 3t3 fibroblast cells because they are well-established and widely used models for studying cell attachment, proliferation, and tissue formation. Their robust and consistent growth characteristics make them ideal for evaluating the biocompatibility of novel biomaterials like the plant-derived scaffolds. If successful, these structures could be a great support for newly formed tissues in the receiving organism. In our in vivo study, we implemented these scaffolds, 1 cm in length and 3mm in thickness, subcutaneously in rats at three different time points: 4 weeks, 8 weeks, and 12 weeks. This study aims to further demonstrate the potential of these plant-derived scaffolds in regenerative medicine, particularly in tissue repair and regeneration.