Characterization Of Schwann Cells On Electroconductive Polymers

Author

Judy Senanayake, Wayne State University

Access Type

WSU Access

Date of Award

January 2024

Degree Type

Dissertation

Degree Name

Ph.D.

Department

Biomedical Engineering

First Advisor

Harini Sundararaghavan

Abstract

At present conductive polymers are being tested widely for many neural applications. The inhibitory environment leading to potential disruptions in motor or sensory pathways post an injury or disease requires characterization to design efficient regenerative therapies. The current work was an attempt to utilize multiple cues tested individually in literature to design a multiple cue model. The model incorporates alignment cues obtained through scaffold fabrication technique (electrospinning), scaffold material (0.01% CNT infused into Hyaluronic Acid fibers (HA)), periodic electrical stimulation (ES) cues and growth factor cues derived from cells as a response to ES. The objectives in this thesis were to 1) study the response of healthy Schwann cells derived from a human donor (WT SCs) to the multi cue model, 2) develop a 3D organotypic model to mimic the Plexiform Neurofibroma (pNF); disease condition with multiple benign peripheral nerve sheath tumors and 3) to study the biomolecular changes observed in immortalized healthy Schwann cells (WT SCs) and mutated Schwann cells from peripheral nerve sheath tumors (NF SCs) to electrical stimulation. We hypothesized that WT SCs characterized in our multiple cue model would demonstrate more proregenerative characteristics due to the combination of multiple cues in a single scaffold and delivery of these cues together at the same time. As the second part of this thesis we are interested in developing 3D organoid model to study pNF tumor cell interaction with our HA-CNT nanofiber scaffold as the ECM architecture to hold and culture the cells. The objective of this portion of the thesis is to evaluate the response of NF SCs on HA-CNT nanofibers combined with electrical stimulation in order to combine these cues to test patient specific cells. We believe that in future this platform could be potentially used to test and prescribe different therapeutic drugs specific to patients’ physiology. The cellular behavior of both WT and NF SCs were studied through different techniques including immunofluorescence stains for morphological analysis, Alama Blue for proliferation studies and ELISA assays for growth factor release quantification. The findings from the aforementioned techniques were further confirmed and correlated to specific genes using quantified Reverse Transcription Polymerase Chain Reaction (qRT-PCR) assays. Our findings on WT cells cultured on HACNT fibers (Hyaluronic Acid Carbon Nanotube) indicated changes in cell morphology compared to control groups of HA and Hydrogels. These results confirmed the effects of biomaterials on cellular morphology. Our stimulation tests further confirmed that cells proliferate faster in the presence of ES and release Neural Growth Factors (NGF). qRT-PCR of the stimulated WT cells expressed NCAM, GFAP, Oct6 and Sox10 genes that correlated to enhanced proliferation and expression of NGF. The NF SCs were unable to respond to ES with similar behavior as WT SCs due to the mutation of neurofibromin (NF+/-) gene. And the most interesting finding of this study was the confirmation of Sox10 gene down regulation in the electrically stimulated NF SCs. As Sox10 dysregulation leads to aberrant proliferation of the mutated SCs in pNF. Our studies offer important insights onto successful utilization of conductive scaffolds with combination of other cues for peripheral nerve regeneration applications and benign nerve sheath tumors causing peripheral neuropathies.

Recommended Citation

Senanayake, Judy, "Characterization Of Schwann Cells On Electroconductive Polymers" (2024). Wayne State University Dissertations. 4003.
https://digitalcommons.wayne.edu/oa_dissertations/4003