Structurally and Functionally Optimized Silk‐Fibroin–Gelatin Scaffold Using 3D Printing to Repair Cartilage Injury In Vitro and In Vivo

Abstract

Articular cartilage repair remains a great challenge for clinicians and researchers. Recently, there emerges a promising way to achieve one-step cartilage repair in situ by combining endogenic bone marrow stem cells (BMSCs) with suitable biomaterials using a tissue engineering technique. To meet the increasing demand for cartilage tissue engineering, a structurally and functionally optimized scaffold is designed, by integrating silk fibroin with gelatin in combination with BMSC-specific-affinity peptide using 3D printing (3DP) technology. The combination ratio of silk fibroin and gelatin greatly balances the mechanical properties and degradation rate to match the newly formed cartilage. This dually optimized scaffold has shown superior performance for cartilage repair in a knee joint because it not only retains adequate BMSCs, due to efficient recruiting ability, and acts as a physical barrier for blood clots, but also provides a mechanical protection before neocartilage formation and a suitable 3D microenvironment for BMSC proliferation, differentiation, and extracellular matrix production. It appears to be a promising biomaterial for knee cartilage repair and is worthy of further investigation in large animal studies and preclinical applications. Beyond knee cartilage, this dually optimized scaffold may also serve as an ideal biomaterial for the regeneration of other joint cartilages.

Self‐assembled biomimetic Nano‐Matrix for stem cell anchorage

“…Although there are many established methods to fabricate tissue regenerative scaffolds, such as 3D print and electrostatic spinning technologies (Buttafoco et al, 2006;Do, Khorsand, Geary, & Salem, 2015;Shi et al, 2017;Yoshimoto, Shin, Terai, & Vacanti, 2003), a premade tissue scaffold with a specific shape is difficult to be implanted into these fracture sites that are deep in the joints. In contrast, our Nano-Matrix can be injected JBNT and FN solutions as liquid into the injured site and then self-assembled into a scaffold for cell anchorage and subsequent tissue regeneration.…”

Microfluidic-based screening of resveratrol and drug-loading PLA/Gelatine nano-scaffold for the repair of cartilage defect

“…will be released around the defects in a short time after the microfracture induced by the articular cartilage defects. Some studies [31,32] reported to use microfracture of joint to stimulate the release of BMSCs and chondrocytes to promote the repair of articular cartilage defects and we adopt the same concept in our study.…”

“…Scaffold plays a key role in tissue engineering, which works as a substrate for cell junctions and growing. In recent years, hydrogel [11], freeze-dried composite scaffold [12], and 3D printing scaffold [13] had been usually used for cartilage repair. However, hydrogel scaffold lacks integral macropores for cell growth and tissue formation, freeze-dried composite scaffold lacks the fibrous structure for cell proliferation, and 3D printing scaffold is limited by high requirement for printing materials.…”

3D bioprinting for cell culture and tissue fabrication

“…As shown in Fig. 3a, in the study by Shi et al the 3D bioprinted scaffold composed of silk fibroin and gelatin has been successfully in vitro cultured and in vivo applied for cartilage injury repair [62]. In another study displayed in Fig.…”