Cell Therapy and Biomaterials: Modern Approaches in the Treatment of Spinal Cord Injury

Spinal cord injury (SCI) is a complex pathology with a multifaceted pathogenesis and, to date, no definitive treatment strategy. Among emerging therapeutic approaches, a combination strategy leveraging biomaterial-based scaffolds for the delivery of both cells and therapeutic agents to the injured spinal cord has shown significant promise. While standalone cell therapies often demonstrate limited efficacy, biomaterial scaffolds can protect transplanted cells from the hostile microenvironment of the injury site and provide a supportive matrix for cell adhesion and subsequent integration into the host neural tissue. Contemporary approaches in cell and organoid therapy, combined with smart biomaterials that can dynamically adapt their properties in response to specific stimuli, present unprecedented opportunities for SCI treatment. This review aims to provide a comprehensive overview of the recent advances in SCI therapies involving cell transplantation and biomaterial scaffolds, with a particular focus on their combinations. It highlights the strengths and limitations of different types of cell transplantation, including less conventional approaches, discusses brain organoid transplantation methods, and identifies the most frequently used scaffold types selected based on their mechanical properties and 3D architecture.