Comparison of bilayered structures of gellan gum with and without incorporation of gold nanorods for osteochondral tissue engineering

In orthopedics, the regeneration and repair of osteochondral defects after trauma, cancer, or metabolic
disorders is still a major clinical challenge, usually leading to an osteoarthritic condition which is a major cause of disability during aging. By the age of 60, close to 100% of the population will have degeneration of knee cartilage. In order to outperform current methods, novel tissue engineering approaches have been proposed to take advantage of the use of stem cells, growth factors and/or preprogramming the stem cells fate, bioreactors and multilayered scaffolds design. The need for simultaneous regenerate both cartilage and subchondral bone in the same scaffold, is a requirement in osteochondral defects.
The incorporation of strategic cues to guide the cell fates towards chondro- and osteogenesis, is an approach to be considered to regenerate both tissues. A previous study performed in our Group showed that the presence of gold nanorods may potentiate the effect of the osteogenic media towards osteocyte-like phenotype, with concomitant reduction of ALP activity and increased mineralization capacity. In the herein
presented work gellan gum-based multilayered structures were developed to recreate the bone, calcified cartilage and hyaline cartilage regions. Gold nanorods (AuNRs) and hydroxyapatite particles were incorporated as it is hypothesized its benefits for promoting the osteogenic differentiation of human fat pad adipose-derived stem cells.