title: A synergistic approach to the design, fabrication and evaluation of 3D printed micro and nano featured scaffolds for vascularized bone tissue repair.
abstract: 3D bioprinting has begun to show great promise in advancing the development of functional tissue/organ replacements. However, to realize the true potential of 3D bioprinted tissues for clinical use requires the fabrication of an interconnected and effective vascular network. Solving this challenge is critical, as human tissue relies on an adequate network of blood vessels to transport oxygen, nutrients, other chemicals, biological factors and waste, in and out of the tissue. Here, we have successfully designed and printed a series of novel 3D bone scaffolds with both bone formation supporting structures and highly interconnected 3D microvascular mimicking channels, for efficient and enhanced osteogenic bone regeneration as well as vascular cell growth. Using a chemical functionalization process, we have conjugated our samples with nano hydroxyapatite (nHA), for the creation of novel micro and nano featured devices for vascularized bone growth. We evaluated our scaffolds with mechanical testing, hydrodynamic measurements and in vitro human mesenchymal stem cell (hMSC) adhesion (4 h), proliferation (1, 3 and 5 d) and osteogenic differentiation (1, 2 and 3 weeks). These tests confirmed bone-like physical properties and vascular-like flow profiles, as well as demonstrated enhanced hMSC adhesion, proliferation and osteogenic differentiation. Additional in vitro experiments with human umbilical vein endothelial cells also demonstrated improved vascular cell growth, migration and organization on micro-nano featured scaffolds.
authors.affiliation: Department of Mechanical and Aerospace Engineering, The George Washington University, Washington DC 20052, USA.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Holmes
authors.forename: Kartik
authors.initials: K
authors.lastname: Bulusu
authors.forename: Michael
authors.initials: M
authors.lastname: Plesniak
authors.forename: Lijie Grace
authors.initials: LG
authors.lastname: Zhang
mesh_terms: D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology*; D001842:Bone and Bones / Q000187:drug effects / Q000502:physiology*; D002448:Cell Adhesion / Q000187:drug effects / Q000502:physiology; D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D049109:Cell Proliferation / Q000187:drug effects / Q000502:physiology; D002478:Cells, Cultured; D017886:Durapatite / Q000737:chemistry; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000187:drug effects / Q000502:physiology; D049329:Nanostructures / Q000737:chemistry*; D010012:Osteogenesis / Q000502:physiology*; D011327:Printing; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D017886:Durapatite