Cartilage tissue engineering on the surface of a novel gelatin–calcium‐phosphate biphasic scaffold in a double‐chamber bioreactor

Abstract

Tissue engineering is a new approach to articular cartilage repair; however, the integration of the engineered cartilage into the host subchondral bone is a major problem in osteochondral injury. The aim of the present work, therefore, was to make a tissue-engineered osteochondral construct from a novel biphasic scaffold in a newly designed double-chamber bioreactor. This bioreactor was designed to coculture chondrocytes and osteoblasts simultaneously. The aim of this study was to prove that engineered cartilage could be formed with the use of this biphasic scaffold. The scaffold was constructed from gelatin and a calcium-phosphate block made from calcined bovine bone. The cartilage part of the scaffold had a uniform pore size of about 180 microm and approximate porosity of 75%, with the trabecular pattern preserved in the bony part of the scaffold. The biphasic scaffolds were seeded with porcine chondrocytes and cultured in a double-chamber bioreactor for 2 or 4 weeks. The chondrocytes were homogeneously distributed in the gelatin part of the scaffold, and secretion of the extracellular matrix was demonstrated histologically. The chondrocytes retained their phenotype after 4 weeks of culture, as proven immunohistochemically. After 4 weeks of culture, hyaline-like cartilage with lacuna formation could be clearly seen in the gelatin scaffold on the surface of the calcium phosphate. The results show that this biphasic scaffold can support cartilage formation on a calcium-phosphate surface in a double-chamber bioreactor, and it seems reasonable to suggest that there is potential for further application in osteochondral tissue engineering.

Engineering Complex Tissues

“…Substrates utilized for these types of constructs have been made from a variety of natural and synthetic materials, but as the substrates are meant to be bone interfacing they must have sufficient strength for weight bearing. [99][100][101][102][103][104][105][106][107][108][109][110][111][112][113][114] A porous ceramic substrate composed of calcium polyphosphate (CPP), which has mechanical properties approximating cancellous bone, has been developed. 117 To generate the biphasic construct, articular chondrocytes are placed on the articulation surface of the CPP substrate.…”

Engineering custom-designed osteochondral tissue grafts

“…To maintain and promote construct maturation, especially for anatomically shaped constructs of a large size, a bioreactor is necessary to provide efficient exchange of nutrients and metabolites. The bioreactor needs to be customized to support the cultivation of anatomically shaped grafts and provide gradients of physical and molecular cues controlling the spatial and temporal patterns of cell differentiation and assembly [14,15].…”

Transplantation of Tissue‐Engineered Osteochondral Plug Using Cultured Chondrocytes and Interconnected Porous Calcium Hydroxyapatite Ceramic Cylindrical Plugs to Treat Osteochondral Defects in a Rabbit Model

“…and many basic research studies on osteochondral repair using the tissue-engineering technique have been developed, some of which have already been applied clinically (18)(19)(20). In 1994, Brittberg et al (5) introduced a new cell technology in which chondrocytes expanded in monolayer culture were transplanted into the cartilage defect of the knee.…”