3D-printed nerve guidance conduits multi-functionalized with canine multipotent mesenchymal stromal cells promote neuroregeneration after sciatic nerve injury in rats

• Published in: Stem cell research & therapy Vol. 12; no. 1; pp. 1 - 303
• Main Authors: Rodríguez-Sánchez, Diego Noé, Pinto, Giovana Boff Araujo, Cartarozzi, Luciana Politti, de Oliveira, Alexandre Leite Rodrigues, Bovolato, Ana Livia Carvalho, de Carvalho, Marcio, da Silva, Jorge Vicente Lopes, Dernowsek, Janaina de Andréa, Golim, Marjorie, Barraviera, Benedito, Ferreira, Rui Seabra, Deffune, Elenice, Bertanha, Mathues, Amorim, Rogério Martins
• Format: Journal Article
• Language: English
• Published: London BioMed Central Ltd 29.05.2021; BioMed Central; BMC
• Subjects: 3-D printers; 3D printing; Autografts; Biological response modifiers; Biopolymers; Biotechnology industry; Brain-derived neurotrophic factor; Canine mesenchymal stem cells; Cell-based therapy; Dendritic branching; Dogs; Fibrin; Gait; Glial cell line-derived neurotrophic factor; Inflammation; Injuries; Interferon; Interleukin 10; Medical equipment; Mesenchymal stem cells; Mesenchyme; Microenvironments; Morphometry; Myelination; Nerve conduction; Nerve guidance conduits; Nerve regeneration; Neurotrophic factors; Polycaprolactone; Recovery of function; Regeneration; Schwann cells; Sciatic nerve; Sciatic nerve injury; Spinal cord; Stem cells; Stromal cells; Tissue engineering; Transplantation; γ-Interferon; Brazil; United States; United States > US; Grand Island New York
• ISSN: 1757-6512; 1757-6512
• DOI: 10.1186/s13287-021-02315-8

Background Nerve injuries are debilitating, leading to long-term motor deficits. Remyelination and axonal growth are supported and enhanced by growth factor and cytokines. Combination of nerve guidance conduits (NGCs) with adipose-tissue-derived multipotent mesenchymal stromal cells (AdMSCs) has been performing promising strategy for nerve regeneration. Methods 3D-printed polycaprolactone (PCL)-NGCs were fabricated. Wistar rats subjected to critical sciatic nerve damage (12-mm gap) were divided into sham, autograft, PCL (empty NGC), and PCL + MSCs (NGC multi-functionalized with 10.sup.6 canine AdMSCs embedded in heterologous fibrin biopolymer) groups. In vitro, the cells were characterized and directly stimulated with interferon-gamma to evaluate their neuroregeneration potential. In vivo, the sciatic and tibial functional indices were evaluated for 12 weeks. Gait analysis and nerve conduction velocity were analyzed after 8 and 12 weeks. Morphometric analysis was performed after 8 and 12 weeks following lesion development. Real-time PCR was performed to evaluate the neurotrophic factors BDNF, GDNF, and HGF, and the cytokine and IL-10. Immunohistochemical analysis for the p75.sup.NTR neurotrophic receptor, S100, and neurofilament was performed with the sciatic nerve. Results The inflammatory environment in vitro have increased the expression of neurotrophins BDNF, GDNF, HGF, and IL-10 in canine AdMSCs. Nerve guidance conduits multi-functionalized with canine AdMSCs embedded in HFB improved functional motor and electrophysiological recovery compared with PCL group after 12 weeks. However, the results were not significantly different than those obtained using autografts. These findings were associated with a shift in the regeneration process towards the formation of myelinated fibers. Increased immunostaining of BDNF, GDNF, and growth factor receptor p75.sup.NTR was associated with the upregulation of BDNF, GDNF, and HGF in the spinal cord of the PCL + MSCs group. A trend demonstrating higher reactivity of Schwann cells and axonal branching in the sciatic nerve was observed, and canine AdMSCs were engrafted at 30 days following repair. Conclusions 3D-printed NGCs multi-functionalized with canine AdMSCs embedded in heterologous fibrin biopolymer as cell scaffold exerted neuroregenerative effects. Our multimodal approach supports the trophic microenvironment, resulting in a pro-regenerative state after critical sciatic nerve injury in rats. Keywords: Canine mesenchymal stem cells, Nerve regeneration, Sciatic nerve injury, Cell-based therapy, Tissue engineering, Nerve guidance conduits, 3D printing, Fibrin, Scaffold