3D printed-electrospun PCL/hydroxyapatite/MWCNTs scaffolds for the repair of subchondral bone

Abstract

Osteochondral defect caused by trauma or osteoarthritis exhibits a major challenge in clinical treatment with limited symptomatic effects at present. The regeneration and remodeling of subchondral bone play a positive effect on cartilage regeneration and further promotes the repair of osteochondral defects. Making use of the strengths of each preparation method, the combination of 3D printing and electrospinning is a promising method for designing and constructing multiscale scaffolds that mimic the complexity and hierarchical structure of subchondral bone at the microscale and nanoscale, respectively. In this study, the 3D printed-electrospun poly(ɛ-caprolactone)/nano-hydroxyapatites/multi-walled carbon nanotubes (PCL/nHA/MWCNTs) scaffolds were successfully constructed by the combination of electrospinning and layer-by-layer 3D printing. The resulting dual-scale scaffold consisted of a dense layer of disordered nanospun fibers and a porous microscale 3D scaffold layer to support and promote the ingrowth of subchondral bone. Herein, the biomimetic PCL/nHA/MWCNTs scaffolds enhanced cell seeding efficiency and allowed for higher cell-cell interactions that supported the adhesion, proliferation, activity, morphology and subsequently improved the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Together, this study elucidates that the construction of 3D printed-electrospun PCL/nHA/MWCNTs scaffolds provides an alternative strategy for the regeneration of subchondral bone and lays a foundation for subsequent in vivo studies.

3D printed osteochondral scaffolds: design strategies, present applications and future perspectives

“…(B) Schematic illustration of the preparation of 3D printed-electrospun biphasic PCL/nHA/MWCNTs scaffold with disordered nanospun fibers above and porous microscale layer below. Reproduced with permission from ( Cao et al, 2023 ). (C) 3D printed biphasic porous scaffold with its cartilage and subchondral layers are made of AS and APS, respectively.…”

“…The preparation of SM/DS- biphasic scaffolds by 3D printing is rarely reported in OC tissue applications. It may be that the change of scaffold structure alone cannot fully utilize the bidirectional effect of osteogenesis and chondrogenesis ( Wang Y. et al, 2022 ; Cao et al, 2023 ). Cao et al, 2023 successfully constructed PCL/nano-hydroxyapatites/multi-walled carbon nanotubes (PCL/nHA/MWCNTs) biphasic scaffolds by the combination of electrospinning and layer-by-layer 3D printing.…”

“…It may be that the change of scaffold structure alone cannot fully utilize the bidirectional effect of osteogenesis and chondrogenesis ( Wang Y. et al, 2022 ; Cao et al, 2023 ). Cao et al, 2023 successfully constructed PCL/nano-hydroxyapatites/multi-walled carbon nanotubes (PCL/nHA/MWCNTs) biphasic scaffolds by the combination of electrospinning and layer-by-layer 3D printing. This dual-scale scaffold consisted of a dense layer of disordered nanospun fibers and a porous microscale 3D scaffold layer to improve the osteogenic differentiation of BMSCs in vitro .…”

Neuro–bone tissue engineering: emerging mechanisms, potential strategies, and current challenges

“… 334 , 335 Similarly, scaffolds or nerve conduits fabricated by combining PLC and carbon nanotubes have been applied to support the ingrowth of subchondral bone and consequently the repair of 10 mm sciatic nerve defects in rats. 336 – 338 …”

Enhanced Cartilage and Subchondral Bone Repair Using Carbon Nanotube-Doped Peptide Hydrogel–Polycaprolactone Composite Scaffolds

“…Incorporating CNTs into PCL scaffolds can enhance cell inoculation efficiency, promote cell interaction, support adhesion and proliferation of bone marrow-derived mesenchymal stem cells (BMSCs), and facilitate osteogenic differentiation in vitro. However, high concentrations of CNT lead to their agglomeration, necessitating their integration with other commonly used materials to ensure safety and maximize their superior properties [ 36 ].…”