A simple technique to create pre-vascularised ‘delivery scaffolds’ for organoid therapies

ABSTRACT The growth in complex cellular constructs such as organoids for disease-modelling or regenerative therapies creates a need to overcome the problem of nutrition-delivery and surgical delivery. This logically requires a ‘pre-vascularised scaffold’, something that can embed and sustain the growth of these constructs and minimise the time needed for blood supply integration on implantation. We present here a series of experiments and their techniques that demonstrate a low-cost fabrication pipeline to create biologically-compatible scaffolds alongside evaluations of their optimal parameters in-vivo, on-CAM and in-vitro using mice and the chick chorioallantoic membrane (CAM) assay as a rapid throughput testbed of scaffolds. Utilising polylactic-glycolic acid (PLGA) scaffolds, we found an optimal range of porosity (300-500um, variable pore size), optimal lactide to glycolide ratio (82:18) and an approximation of the optimal cell seeding density using reset-vascular endothelial cells (R-VECs). Finally, we demonstrate a method to delineate the internal vascular network of these scaffolds with micro-computer-tomography (MicroCT), a low-cost analytical method that may become useful for network analysis in regenerative medicine research. Competing Interest Statement The authors have declared no competing interest.