In the quest of the optimal chondrichthyan for the development of collagen sponges for articular cartilage

The limited capability of articular cartilage to self-repair renders its regeneration a formidable challenge. In the quest of the optimal material for cartilage scaffold fabrication, the use of collagen type II has been advocated, but its optimal source still remains elusive. Herein, the potential of four [lesser spotted dogfish (Scyliorhinus canicula), thorn back ray (Raja clavata), cuckoo ray (Leucoraja naevus) and blonde ray (Raja brachyuran)] cartilaginous fish (chondrichthyes) derived collagen type II preparation in cartilage engineering was assessed. Collagen type II was extracted using the acid-pepsin method, crosslinked with 4-arm poly (ethylene glycol) succinimidyl glutarate sponges were fabricated and their biophysical, biochemical and biological properties were assessed. Pure collagen type II preparations were obtained from all four chondrichthyes, as revealed by gel electrophoresis. Pore size, porosity, mechanical properties, denaturation temperature, free amine content and resistance to enzymatic degradation of the produced sponges were not significantly (p > 0.05) affected as a function of species. Biological analysis using human adipose derived stem cells revealed no significant (p > 0.05) differences between the groups in cell viability, DNA concentration, metabolic activity, Alcian blue staining and sulphated glycosaminoglycans synthesis. Human adipose derived stem cells seeded on fish-derived scaffolds expressed lower mRNA levels of COL1A1 (fold change ≥ 2.0) and COL3A1 (apart from lesser spotted dogfish; fold change < 2.0) and higher mRNA levels of COL10A1 (fold change ≥ 2.0), COMP (fold change ≥ 2.0), SOX9 (fold change ≥ 2.0), and ACAN (apart from cuckoo ray; fold change < 2.0) than cells grown on tissue culture plastic. Our data suggest that chondrichthyes derived collagen type II has the potential to be used in cartilage engineering.