Heart disease and stroke, the first cause of death worldwide, demand development of novel endovascular implant technologies as well as advanced methods for their pre-clinical investigation. While the state of the art in-vitro test models generally misses crucial biological factors such as the presence of endothelium, in-vivo tests have been performed with ethical concerns, high costs limitations and non-reproducibility.

Plant scaffolds have attracted the interest of researchers due to their low cost, biocompatibility and owning natural microstructure supporting seeded cells. We present a new approach based on using biologized tubular plants for investigating cardio- and neurovascular implants in cardiovascular research. The so-called “Green Vessels” are aimed at providing a biological, reproducible environment for preclinical research on novel therapies, facing the mean limitations of current models. In our study, we developed and evaluated the decellularization of natural tubular plant structures as the first step to generate novel scaffolds.

A pre-selection among various tubular plants was performed according to the following criteria: geometry and dimensions (inner diameter in the range between 3 and 7,5 mm); stability and integrity before and after decellularization; and withstanding flow (50 rpm) when connected to a peristaltic pump. In order to remove host cells of the plant samples (decellularization), an in-house automated set-up was developed. After the connection of up to 7 samples, desired chemicals were selected and automatically perfused into the decellularization loop under controlled temperature and flow rate over 7 days. After performing the decellularization process, DNA quantification tests, as well as SEM and confocal microscopy, were carried out for both native and decellularized samples to evaluate complete decellularization and scaffold microstructure, respectively. Withstanding of the plant scaffolds under continuous and pulsatile flow conditions as well as the feasibility of self-expandable stents implantation were assessed.

In the further stage, the decellularized tubular plants will be recellularized (biologized) with human endothelial cells in a dedicated, self-made bioreactor providing connections and slow rotation of the scaffolds to provide homogenous cell seeding. Finally, the biologized models will be evaluated in the terms of cell confluency and stability over time and under mechanical stresses. In our presentation, we will present the first results and discuss the potential and challenges of the new plant-based models.

Ali Salehi (M.Sc.)