Ex Vivo Preservation of Ovine Periosteum Using a Perfusion Bioreactor System

Abstract

Periosteum is a highly vascularized membrane lining the surface of bones. It plays essential roles in bone repair following injury and reconstruction following invasive surgeries. To broaden the use of periosteum, including for augmenting in vitro bone engineering and/or in vivo bone repair, we have developed an ex vivo perfusion bioreactor system to maintain the cellular viability and metabolism of surgically resected periosteal flaps. Each specimen was placed in a 3D printed bioreactor connected to a peristaltic pump designed for the optimal flow rates of tissue perfusate. Nutrients and oxygen were perfused via the periosteal arteries to mimic physiological conditions. Biochemical assays and histological staining indicate component cell viability after perfusion for almost 4 weeks. Our work provides the proof-of-concept of ex vivo periosteum perfusion for long-term tissue preservation, paving the way for innovative bone engineering approaches that use autotransplanted periosteum to enhance in vivo bone repair.

From Free Tissue Transfer to Hydrogels: A Brief Review of the Application of the Periosteum in Bone Regeneration

“…However, the use of a periosteum for scaffold fabrication requires a feasible ex vivo approach in which the tissue viability of the harvested periosteum is preserved. Xin et al used a perfusion bioreactor system as demonstrated in Figure 3 in which an ovine periosteal flap was placed in a 3-D printed bioreactor and perfused with a culture medium via its artery [ 15 ]. Both live and dead assays, PrestoBlue assays, and a histology analysis suggested that a significant proportion of cells were still viable after being perfused for up to 4 weeks.…”

“…As a proof-of-concept study, the proposed ex vivo perfusion system was shown to be a feasible solution for preserving a harvested periosteum for a prolonged period for upcoming scaffold vascularization. However, several key system parameters still need to be optimized, such as the flow rate, pressure, and culture medium formulation [ 15 ]. These factors have been proven important in previous similar studies in which the researchers attempted to perfuse scaffold constructs seeded with osteogenic cells to study bone biology, proliferation, and gene expression [ 74 , 75 , 76 ].…”

“… The concept of ex vivo perfusion bioreactor system to maintain the tissue viability of a periosteum procured from an ovine model, adapted from [ 15 ]. In the system, the culture media containing oxygen and nutrients were introduced into the periosteal vascular network via its artery, using a circulating pump.…”

“…In the system, the culture media containing oxygen and nutrients were introduced into the periosteal vascular network via its artery, using a circulating pump. The cellular viability of the tissue was reported to be preserved for up to 4 weeks [ 15 ].…”

“…It is an essential component for bone development, facture healing, and regeneration [ 12 , 13 ]. Research on the use of the periosteum in BTE has expanded from simply transplanting the periosteum for in vivo bone growth to in vitro periosteal cell isolation and expansion [ 14 ], periosteal perfusion [ 15 ], and periosteum engineering [ 16 ]. Much of this research has involved hydrogels as promising materials for fabricating artificial periostea owing to their biocompatibility and tunable mechanical, osteoconductive, and osteoinductive properties [ 1 , 17 ].…”