Traumatic spinal cord injury (SCI) is a global health problem involving complex pathophysiological cascade and afflicts both developing and developed countries. Transplantation of Mesenchymal stem cell population such as dental stem cells (DSC) have demonstrated preclinical potential for central nervous system (CNS) repair. The work presented in this thesis has evaluated the potential of dental stem cells from apical papillae (SCAP) in combination with different biomaterials for SCI repair. ECM scaffolds were produced from different mammalian tissues including spinal cord, bone and dental hard tissue using different decellularisation processes. Scaffolds were then digested with pepsin to allow solubilisation and hydrogel formation. The ECM hydrogels were characterised and embedded with SCAP to investigate the effect of morphological and biochemical properties upon cell characteristics. All the hydrogels maintained high cell viability and an increase in the cell number with a satisfactory metabolic activity. However, only ECM hydrogels from decellularised spinal cord and bone tissue supported the expression of neural lineage and pro angiogenic markers with stronger responses observed with spinal cord ECM hydrogels. Biodegradable PLGA-Triblock (PLGA-TB) microparticles were fabricated to provide controlled release of glial cell derived neurotrophic factor (GDNF) and may facilitate SCAP attachment. An optimal PLGA-TB microparticle formulation was selected based on the size, surface morphology and release profile achieved. All commercial preparation of GDNF being stabilised in salt, a modified protocol was required to prepare microparticles. The formulation was modified with 10mM sodium acetate which led to a successful encapsulation and sustained release of bioactive GDNF. To support SCAP attachment and survival, PLGA-TB microparticles surfaces were coated with different ECM pre-gel solutions (spinal cord and bone tissue ECM) and laminin. Assessment of surface coating with ToF-SIMS showed protein adsorption on all the coated microparticles, with a higher adsorption on ECM pre-gel coated microparticles. All the surface modified PLGA-TB microparticles supported prolonged SCAP attachment and survival. Laminin and bone ECM pre-gel coated microparticles promoted a significant increase in SCAP number after 7 days. Over all, the result in this thesis have shown that SCAP combined with decellularised mammalian tissue derived ECM hydrogels or GDNF loaded PLGA-TB microparticles may facilitate delivery of autologous stem cells to promote spinal cord repair.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:748205 |
| Date | January 2018 |
| Creators | Viswanath, Aiswarya |
| Publisher | University of Nottingham |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://eprints.nottingham.ac.uk/47606/ |
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