Designed Biomaterial-Enhanced Cell Transplantation for Neural Tissue Engineering

Abstract

Cell transplantation therapy in the central nervous system is hindered by limited survival and integration of grafted cells. Biomaterials have emerged as an attractive solution to this problem by providing a protective microenvironment to deliver cells to injured tissues. The design of biomaterials compatible with nervous tissues to promote tissue repair and functional recovery is a focus of neural tissue engineering. A wealth of research has explored different materials and architectures in combination with bioactive cues to promote neural and glial cell growth and maturation. After a brief presentation of biomaterial strategies and cell sources, we review the in vivo evidences about the efficacy of biomaterial and stem cell cotransplantation in (i) enhancing trophic effects, (ii) increasing cell integration, and (iii) achieving functional recovery in preclinical models of stroke, traumatic brain injury, Parkinson's disease, and spinal cord injury. Furthermore, a comprehensive perspective was offered regarding the specific implementation tactics, obstacles, and development orientations of employing biomaterials as critical support to promote cell transplantation.

Keywords

biomaterial-enhanced cell transplantation / central nervous system repair / neural tissue engineering / trophic effects / functional recovery

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