Design–Build–Validate Strategy to 3D Print Bioglass Gradients for Anterior Cruciate Ligament Enthesis Reconstruction

• Published in: Tissue engineering. Part C, Methods Methods, 2022-04, Vol.28 (4), p.158-167
• Main Authors: Kajave, Nilabh S, Schmitt, Trevor, Patrawalla, Nashaita Y, Kishore, Vipuil
• Format: Article
• Language: English
• Subjects: Anterior Cruciate Ligament - surgery; Anterior Cruciate Ligament Reconstruction - methods; Ceramics; Collagen - chemistry; Humans; Methods; Methods Articles
• ISSN: 1937-3384; 1937-3392
• DOI: 10.1089/ten.tec.2022.0035

A rupture of the anterior cruciate ligament (ACL) is one of the most common knee ligament injuries affecting the young and active population. Tissue engineering strategies to reconstruct the damaged ACL have met with significant challenges mainly associated with poor graft integration at the bone–ligament interface (i.e., enthesis). In this study, a “design–build–validate” strategy was employed by combining 3D Raman spectral mapping and 3D printing to develop a tissue engineered scaffold that is compositionally similar to the ACL bone–ligament interface and can provide the essential biochemical cues to promote interface regeneration and facilitate functional graft to bone integration. Results showed that Raman spectroscopy is a highly efficient nondestructive technique to determine the biochemical composition of native ACL enthesis. 3D printing using combinatory inks consisting of different compositions of methacrylated collagen (CMA) and Bioglass (BG) allowed for the fabrication of BG gradient-incorporated collagen matrices (BioGIMs) with a transition region confirmed by Alizarin red S staining. Furthermore, Raman spectroscopy validated replication of ACL enthesis composition in BioGIMs. In addition, human mesenchymal stem cells (hMSCs) cultured on BioGIMs showed morphological differences along the length of the BioGIMs as evidenced by confocal microscopy of cell cytoskeleton-stained images indicating that the cells can sense the underlying differences in matrix composition. Overall, the “design–build–validate” strategy developed in this study has significant potential to generate biomimetic tissue constructs for use at the interface regions of synthetic grafts to promote better host integration and achieve full reconstruction of the ACL.