Osteogenic Differentiation and Mineralization on Compact Multilayer nHA-PCL Electrospun Scaffolds in a Perfusion Bioreactor

Abstract

Background:Monolayer electrospun scaffolds have already been used in bone tissue engineering due to their high surface-tovolume ratio, interconnectivity, similarity to natural bone extracellular matrix (ECM), and simple production. Objectives: The aim of this study was to evaluate the dynamic culture effect on osteogenic differentiation and mineralizationi into a compact cellular multilayer nHA-PCL electrospun construct. The dynamic culture was compared with static culture. Materials and Methods:The calcium content, alkaline phosphatase (ALP) activity and cell viability were investigated on days 3 and 7. Results: When the dynamic culture compared to static culture, the mineralization and ALP activity were increased in dynamic culture. After 7 days, calcium contents were 41.24 and 20.44 μg.(cm 3 ) -1 , and also normalized ALP activity were 0.32 and 0.19 U.mg -1 in dynamic and static culture, respectively. Despite decreasing the cell viability until day 7, the scanning electron microscopy (SEM) results showed that, due to higher mineralization, a larger area of the construct was covered with calcium deposition in dynamic culture. Conclusions:The dynamic flow could improve ALP activity and mineralization into the compact cellular multilayer construct cultured in the perfusion bioreactor after 7 days. Fluid flow of media helped to facilitate the nutrients transportation into the construct and created uniform cellular construct with high mineralization. This construct can be applied for bone tissue engineering.

3D Bioprinting of Prevascularised Implants for the Repair of Critically Sized Bone Defects

“…Although vascularisation of the defect site is a key component of tissue regeneration and was significantly improved by the implantation of a prevascularised scaffold, successful bone healing relies on a number of factors, including the delivery of osteoinductive cues. Although the presence of nHA on the PCL scaffolds has been shown to enhance osteogenesis [82] , perhaps the prolonged benefits of prevascularisation would be more evident when included in a more potent osteogenic tissue engineered scaffold. While full defect bridging was not seen in either group after 12 weeks, the presence of cartilage in a subset of the PV scaffold group at 12 weeks may indicate that the healing process was continuing for those animals.…”