Bioorthogonal Click Chemistry Enables Stable Cell Attachment to Silk Fibroin Scaffolds for Tissue Engineering Applications: Proof of Concept in Neural Regeneration.

Tissue engineering seeks effective strategies to integrate cells into scaffolds while preserving spatial organization and stability. Conventional approaches based on extracellular matrix molecules or adhesion peptides often provide weak and nonspecific attachments, limiting robust assembly of complex cellular architectures. Here, we investigate biorthogonal click chemistry to address these limitations. By enabling covalent cell-biomaterial bonding through strain-promoted azide-alkyne cycloaddition (SPAAC), we achieved stable cell-scaffold integration. As a proof of concept, we engineered artificial Bands of Büngner-like scaffolds by functionalizing silk microfibers with cyclooctyne groups and metabolically engineering Schwann cells to present azide functionalities. Over 15 days in vitro, these biohybrid scaffolds supported directed neurite outgrowth, preserved metabolic activity, and increased nerve growth factor levels at early time points. Our results support click chemistry as a robust strategy for assembling stable cell-laden scaffolds while preserving biological function, potentially enabling the tailored design of complex cellular architectures and microenvironments for tissue engineering applications.