Orderly osteochondral regeneration in a sheep model using a novel nano‐composite multilayered biomaterial

Abstract

The objective of this article was to investigate the safety and regenerative potential of a newly developed biomimetic scaffold when applied to osteochondral defects in an animal model. A new multilayer gradient nano-composite scaffold was obtained by nucleating collagen fibrils with hydroxyapatite nanoparticles. In the femoral condyles of 12 sheep, 24 osteochondral lesions were created. Animals were randomized into three treatment groups: scaffold alone, scaffold colonized in vitro with autologous chondrocytes and empty defects. Six months after surgery, the animals were sacrificed and the lesions were histologically evaluated. Histologic and gross evaluation of specimens showed good integration of the chondral surface in all groups except for the control group. Significantly better bone regeneration was observed both in the group receiving the scaffold alone and in the group with scaffold loaded with autologous chondrocytes. No difference in cartilage surface reconstruction and osteochondral defect filling was noted between cell-seeded and cell-free groups. In the control group, no bone or cartilage defect healing occurred, and the defects were filled with fibrous tissue. Quantitative macroscopic and histological score evaluations confirmed the qualitative trends observed. The results of the present study showed that this novel osteochondral scaffold is safe and easy to use, and may represent a suitable matrix to direct and coordinate the process of bone and hyaline-like cartilage regeneration. The comparable regeneration process observed with or without autologous chondrocytes suggests that the main mode of action of the scaffold is based on the recruitment of local cells. ß

Ex vivo model unravelling cell distribution effect in hydrogels for cartilage repair_suppl

“…This observation is in line with other studies that demonstrated that differences in DNA levels and tissue formation due to different initial cell densities disappear during long-term culture (Hansen et al, 2013;Kon et al, 2010). However, other studies reported beneficial effects of increased cell densities using higher initial cell densities compared to the current study (Chen et al, 1997;Puelacher et al, 1994;Talukdar et al, 2011).…”

Autologous cartilage fragments in a composite scaffold for one stage osteochondral repair in a goat model

“…Maioregen (Fin-Ceramica Faenza S.p.A., Faenza-Italy) is a thick, nanostructured biomimetic collagen and hydroxyapatite scaffold used for treatment of large osteochondral lesions. As in the AMIC technique, cell migration from the surrounding host bone and bone marrow is required in order to colonise the scaffold and achieve functional repair (Kon et al, 2010a;2010b). Osteochondral morselised grafts have been proposed as a "paste" without any scaffold for one-stage repair of full thickness articular cartilage lesions and osteochondral defects, both in animal and human studies (Stone et al, 2006;Mahadev et al, 2001).…”

Microsphere-Based Gradient Implants for Osteochondral Regeneration: a Long-Term Study in Sheep

“…It is known that the quality of cartilage regenerated in an empty osteochondral defects is of poor quality. Previous reports indicate that in empty osteochondral control defects neither bone nor cartilage is formed; the repair tissue formed is fibrous or a mixed-type fibrocartilage tissue with poor integration with the surrounding cartilage [44,[54][55]. In our study we used a gradient 3D osteochondral scaffold that encapsulated raw materials, chondrodroitin sulfate and β tricalcium phosphate.…”