Mini-review: advances in 3D bioprinting of vascularized constructs

Lorenzo Bova,Fabrizio Billi,Elisa Cimetta

doi:10.1186/s13062-020-00273-4

Abstract

3D in vitro constructs have gained more and more relevance in tissue engineering and in cancer-modeling. In recent years, with the development of thicker and more physiologically relevant tissue patches, the integration of a vascular network has become pivotal, both for sustaining the construct in vitro and to help the integration with the host tissue once implanted. Since 3D bioprinting is rising to be one of the most versatile methods to create vascularized constructs, we here briefly review the most promising advances in bioprinting techniques.

Highlights

Almost 30 years after Langer [1] introduced the concept of tissue engineering, the field has seen huge progress; in vitro-created tissue patches and organs have already reached clinical use, albeit many challenges are yet to be overcome
Et al created a vascularized construct printing a sacrificial 3D Pluronic F-127 (PLU) freestanding structure and surrounding it with cell-laden gelatin methacrylate (GelMA) (Fig. 1d-g); the construct was implanted in a femoral defect in a rat model, showing a higher host osteoclasts and immune cells invasion compared to a non-vascularized construct [20]
The surrounding hydrogel containing human neonatal dermal fibroblasts; b picture of the final bioreactor containing the tissue construct; c confocal image of a cross-section after 30 days of perfusion; the construct is densely populated by viable cells with a higher osteocalcin expression the closer they are to the channels; human umbilical vein endothelial cell (HUVEC) surrounding the internal cavity of the channels are visible. d-g “Implantable vascularized construct for bone repair”. d Schematic representation of the vascularized construct; e freestanding filament network printed with PLU; f final GelMA construct after PLU wash out; g fluorescence image showing live/dead MSCs 24 h after fabrication, scale bar 500 μm

Summary

Introduction

Almost 30 years after Langer [1] introduced the concept of tissue engineering, the field has seen huge progress; in vitro-created tissue patches and organs have already reached clinical use, albeit many challenges are yet to be overcome. 3D bioprinting has risen as one of the most promising engineering techniques to manufacture in vitro tissues, paving the way to create thick cell-laden constructs [7, 8].

Results

Conclusion