Microporous Polylactic Acid Scaffolds Enable Fluorescence-Based Perfusion Imaging of Intrinsic In Vivo Vascularization

Technology for the formation of engineered microvascular network models and their biomedical applications

Tissue engineering and regenerative medicine have made great progress in recent decades, as the fields of bioengineering, materials science, and stem cell biology have converged, allowing tissue engineers to replicate the structure and function of various levels of the vascular tree. Nonetheless, the lack of a fully functional vascular system to efficiently supply oxygen and nutrients has hindered the clinical application of bioengineered tissues for transplantation. To investigate vascular biology, drug transport, disease progression, and vascularization of engineered tissues for regenerative medicine, we have analyzed different approaches for designing microvascular networks to create models. This review discusses recent advances in the field of microvascular tissue engineering, explores potential future challenges, and offers methodological recommendations.

Surface Modification of Polylactic Acid Bioscaffold Fabricated via 3D Printing for Craniofacial Bone Tissue Engineering

Bone tissue engineering is a promising solution for advanced bone defect reconstruction after severe trauma. In bone tissue engineering, scaffolds in three-dimensional (3D) structures are crucial components for cell growth, migration, and infiltration. The three-dimensional printing technique is well suited to manufacturing scaffolds since it can fabricate scaffolds with highly complex designs under good internal structural control. In the current study, the 3D printing technique was utilized to produce polylactic acid (PLA) scaffolds. BMSCs were seeded onto selected scaffolds, either hydrogel-mixed or not, and cultivated in vitro to investigate the osteogenic potential in each group. After osteogenic incubation in vitro, BMSC-seeded scaffolds were implanted onto rat cranium defects, and bone regeneration was observed after 12 weeks. Our results demonstrated that BMSCs were able to seed onto 3D-printed PLA scaffolds under high-resolution observation. Real-time PCR analysis showed their osteogenic ability, which could be further improved after BMSCs were mixed with hydrogel. The in vivo study showed significantly increased bone regeneration when rats' cranium defects were implanted with a hydrogel-mixed BMSC-seeded scaffold compared to the control and those without cell or hydrogel groups. This study showed that 3D-printed PLA scaffolds are a feasible option for BMSC cultivation and osteogenic differentiation. After mixing with hydrogel, BMSC-seeded 3D-printed scaffolds can facilitate bone regeneration.