M. Terpstra (Utrecht, NL)
University Medical Center Utrecht OrthopaedicsPresenter Of 1 Presentation
24.1.7 - Bioink With Cartilage-Derived ECM Microfibers Enables Spatial Control of Vascular Capillary Formation in Bioprinted Constructs
Abstract
Purpose
Within biofabrication, the recreation of spatially distributed vasculature is paramount, as vascular capillary ingrowth into avascular tissues can lead to tissue matrix alterations, and subsequent pathology. Multi-material 3D bioprinting is a potentially tool to recreate complex anisotropic tissue features, although to date, building complex constructs with stable vascularized and non-vascularized regions remains a challenge.
Methods and Materials
We developed a pro- and anti-angiogenic bioink by the supplementation of type I collagen (col-1) microfibers (MFs), and decellularized cartilage-derived (CdECM) MFs respectively, to an endothelial cell (EC)-laden fibrin-based bioink. By extrusion-based bioprinting, the bioinks were deposited into an anatomical meniscus shaped construct with a biomimetic outer vascularized zone containing ECs and mesenchymal stromal cells (MSCs), and an inner fibrocartilagenous zone with meniscus progenitor cells (MPCs), cultured for 14 days. To co-facilitate both microvessel formation and MPC-derived matrix formation, we tested different compositions of chondrogenic and endothelial cell culture medium formulations.
Results
The supplementation of CdECM MFs to the EC-laden fibrin-based bioinks lead to a reduction of the total microvessel length of 29%, as compared to supplementation of pro-angiogenic col-1 MFs (Figure 1). After 3D bioprinting of the zonal meniscus construct, the vascular network was confined in the outer zone (Figure 2). The co-culture of ECs and MPCs was succesful by switching from endothelial cell culture medium (EGM-2) to 10 or 25% v/v chondrogenic differentiation medium in EGM-2 medium at day 7, resulting in both EC-derived vascular networks and MPC type I collagen deposition.
Figure 1
Figure 2
Conclusion
Here, we present two bioinks that facilitate and inhibit vascular formation, by supplementation of col-1 or CdECM MFs, which were bioprinted in a biomimetic meniscus construct. This provides new strategies for grafts development of partially avascular tissues, and applications including in vitro models of vascular-to-avascular tissue interfaces, cancer progression, and for testing anti-angiogenic therapies.