Tissue engineering of biphasic cartilage constructs using various biodegradable scaffolds: an in vitro study

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Orthopedic Research

Background:

• Osteochondral defects require subchondral support and hyaline cartilage regeneration.
• Biphasic implants offer a potential solution by combining neocartilage with a biodegradable base.
• Evaluating biodegradable materials for osteoconductive support is crucial for effective repair.

Purpose of the Study:

• To investigate biodegradable materials as osteoconductive bases for neocartilage formation in vitro.
• To compare the performance of poly-L-lactide [P(L)LA], poly-d,l-lactide [P(D,L)LA], and Collagen-hydroxyapatite [Col-HA] scaffolds.
• To assess the viability, morphology, and integration of neo-cartilage on different biomaterials.

Main Methods:

• Porcine chondrocytes were seeded onto P(L)LA, P(D,L)LA, or Col-HA biomaterial bases.
• Constructs were cultured in a static bioreactor for 15 weeks to promote neocartilage development.
• Cellular colonization, biomaterial degradation, and construct morphology were evaluated.

Main Results:

• Viable neo-cartilage formed on all tested biomaterials, with varying degrees of cellular colonization.
• P(D,L)LA exhibited rapid, uneven degradation, resulting in irregular construct shapes.
• P(L)LA showed minimal degradation and limited chondrocyte colonization.
• Col-HA constructs demonstrated superior cell viability, consistent morphology, and better integration between neo-cartilage and the base.

Conclusions:

• Collagen-hydroxyapatite [Col-HA] is a promising biomaterial for the osteoconductive base in biphasic implants for osteochondral defect repair.
• The developed in vitro system shows potential for creating functional biphasic implants.
• Further research is warranted to optimize biphasic implant design for clinical application in osteochondral regeneration.