Cartilage Tissue Construct from Human Adipose-Derived Mesenchymal Stem Cells on 3D-Printed Polylactic Acid Scaffold

Polylactic acid (PLA) is a synthetic biodegradable filament amenable to three-dimensional (3D) printing for cartilage tissue engineering applications. The 3D-printed PLA scaffold affords a conducive extracellular matrix (ECM) for the differentiation of mesenchymal stem cells (MSCs) to chondrocytes and generating cartilage mimetic tissue.

Herein, we 3D printed the PLA scaffold using computer-aided design software with a pore size of 0.1 mm and seeded it with human adipose-derived stem cells (ADSCs) for chondrogenesis. Furthermore, we evaluated the chondrogenic differentiation potential of ADSCs by cellular morphology (safranin O), sulfated glycosaminoglycans (GAGs) deposition (alcian blue), cellular viability (tryphan blue exclusion), growth kinetics (population doubling) and hyaline-type cartilage ECM-specific markers (collagen type II, aggrecan, laminin) characterisation using phase contrast microscopy, histology and confocal microscopy.

The PLA scaffold showed biocompatibility with proliferation and differentiation of ADSCs cultured over 21 days. The safranin O and alcian blue staining showed cellular chondrocyte morphology with deposition of sulfated GAGs respectively. The cellular passages showed viability reaching 93% with a considerable significant difference in population doubling from day 0 to day 21 with p < 0.05. The serial Z stacking (thickness of 146.5 µm) with confocal imaging, revealed ECM marker expression, including collagen type II typical of hyaline cartilage, aggrecan specific for proteoglycans, laminin for cellular-scaffold adherence and collagen type I.

Thus, the study presents a patient-specific tailored choice for bioprinting PLA scaffold as a biocompatible alternative to traditional implants for ADSCs-driven tissue development in treatment of personalised cartilage focal defects.

In this study, we explored the use of 3D-printed polylactic acid (PLA) scaffold for cartilage tissue engineering. PLA is a biodegradable material that provides structural support for the growth and differentiation of mesenchymal stem cells (MSCs) into chondrocytes. The PLA scaffold was seeded with adipose-derived stem cells (ADSCs) for chondrogenesis. The cartilage-like tissue construct cultured for 21 days was characterised by direct and paraffin-embedding approaches and observed for their cellular proliferation, morphology, glycosaminoglycans accumulation, viability, growth kinetics and hyaline cartilage marker expression. The results showed that the scaffold was biocompatible and supported the ADSCs differentiation into cartilage-like tissue. Thus, the study highlights the potential of 3D-printed PLA scaffold in cartilage tissue engineering with translational potential of decellularised ECM as bioink additive.