Subcutaneous priming of protein-functionalized chitosan scaffolds improves function following spinal cord injury

Publication date: Available online 10 January 2020Source: Materials Science and Engineering: CAuthor(s): Trevor R Ham, Dipak D Pukale, Mohammad Hamrangsekachaee, Nic D LeipzigAbstractStrategies using neural stem cells (NSCs) to aid regeneration following spinal cord injury (SCI) show much promise, but challenges remain regarding implementation and efficacy. In this work, we explored the use of an NSC-seeded scaffold consisting of covalently immobilized interferon-γ and rat NSCs within a hydrogel matrix (methacrylamide chitosan). We placed the scaffolds within the subcutaneous environment of rats, allowing them to incubate for 4 weeks in order to prime them for regeneration prior to being transplanted into a right lateral hemisection SCI model in the same animal. We found that subcutaneous priming reduced the lineage commitment of encapsulated NSCs, as observed by increased nestin expression and decreased NeuN expression. When combined with intracellular σ peptide administration (which reduces inhibition from the glial scar), subcutaneous maturation improved functional outcomes, which were assessed by BBB score and quantitative gait parameters (fore and hind limb duty factor imbalance, right and left paw placement accuracy). Although we did not observe any direct reconnection of the transplanted cells with the host tissue, we did observe neurofilament fibers extending from the host tissue into the scaffold. Importantly, the mechanism for improved functional outcomes is likel...
Source: Materials Science and Engineering: C - Category: Materials Science Source Type: research