Photo‐Polymerizable Autologous Growth‐Factor Loaded Silk‐Based Biomaterial‐Inks toward 3D Printing‐Based Regeneration of Meniscus Tears

Abstract

Meniscus tears in the avascular region undergoing partial or full meniscectomy lead to knee osteoarthritis and concurrent lifestyle hindrances in the young and aged alike. Here they reported ingenious photo‐polymerizable autologous growth factor loaded 3D printed scaffolds to potentially treat meniscal defects . A shear‐thinning photo‐crosslinkable silk fibroin methacrylate–gelatin methacrylate–polyethylene glycol dimethacrylate biomaterial‐ink is formulated and loaded with freeze‐dried growth factor rich plasma (GFRP) . The biomaterial‐ink exhibits optimal rheological properties and shape fidelity for 3D printing. Initial evaluation revealed that the 3D printed scaffolds mimic mechanical characteristics of meniscus, possess favourable porosity and swelling characteristics, and demonstrate sustained GFRP release. GFRP laden 3D scaffolds are screened with human neo‐natal stem cells in vitro and biomaterial‐ink comprising of 25 mg mL−1 of GFRP (GFRP25) is found to be amicable for meniscus tissue engineering. GFRP25 ink demonstrated rigorous rheological compliance, and printed constructs demonstrated long term degradability (>6 weeks), GFRP release (>5 weeks), and mechanical durability (3 weeks). GFRP25 scaffolds aided in proliferation of seeded human neo‐natal stem cellsand their meniscus‐specific fibrochondrogenic differentiation . GFRP25 constructs show amenable inflammatory response in vitro and in vivo. GFRP25 biomaterial‐ink and printed GFRP25 scaffolds could be potential patient‐specific treatment modalities for meniscal defects.

Trends and advances in silk based 3D printing/bioprinting towards cartilage tissue engineering and regeneration

“…Furthermore, viscosity of silk fibroin solution limits its applications with regard to shape fidelity after printing using extrusion-based printing techniques. In order to enhance the functional properties and emulate the complexity of ECM and different cellular layers of cartilage, silk fibroin bioinks have been combined with other natural and synthetic polymers such as hyaluronic acid, alginate, chitosan, PEG, polyethylene glycol diacrylate (PEGDA) etc [136,105]. PEG and glycerol have been combined with silk fibroin-based bioinks as rheological modifiers to improve the silk printability and stability of bioprinted constructs.…”

“…Transforming growth factor-β1 loaded chitosan nanoparticles and bone morphogenetic protein-2 incorporated SF hydrogels enhanced the chondrogenic ability of bone marrow stromal cells both in vitro and in vivo [104]. SF-based constructs have also been used for the regeneration of fibrocartilaginous tissues like meniscus [105] and intervertebral discs. Bandyopadhyay et al developed a SF and gelatin-based scaffold for meniscus tissue repair.…”