Development and Characterization of Tunable, Bioinspired Electrospun Constructs for Skeletal Muscle Engineering

Volumetric muscle loss, as a result of high intensity sports injury, trauma or tumor ablation, affects more than 250,000 civilians each year in the U.S. alone and accounts for more than 50% of all DoD disabilities. These injuries often leave patients with permanent structural and functional deficits in the injured muscle and surrounding tissues. With clinical treatments failing to repair lost tissue, there is a great need for tissue-engineered therapy to promote skeletal muscle regeneration. This thesis focused on the development of a bio-rich material with tunable physicochemical properties to direct the regeneration of skeletal muscle. By leveraging the biochemical cues from decellularized skeletal muscle with the tunable material properties afforded through electrospinning, we were able to fabricate bioactive constructs with modular material properties in clinically-relevant shapes and sizes. After confirming the appropriate decellularization of skeletal muscle, the natural polymer was electrospun with varying degrees of fiber alignment and varying degrees of crosslinking. The impact of scaffold architecture and crosslinking density on fiber swelling, degradation kinetics, and mechanical properties was then evaluated. After confirming that the material properties of skeletal muscle-derived constructs could be modulated, the effects of fiber alignment and crosslinking density on cell growth and proliferation were assessed in vitro. Cell growth, alignment, and myogenic differentiation were assessed qualitatively and quantitively in response to biomaterial cues. It was found that higher fiber orientation produced more aligned myotubes after 7 days in induction media. Completely crosslinked scaffolds were also found to inhibit growth and differentiation regardless of fiber orientation, likely due to the decreased access to bioactive molecules within the biomaterial. Finally, the best performing construct from in vitro analyses was evaluated within a rat volumetric muscle loss defect. After creating a defect in the right tibialis anterior muscle, electrospun scaffolds were sutured against existing muscle. After 8 weeks, rats were euthanized and implants were extracted and assessed for cell infiltration and muscle regeneration. The completion of this thesis has provided new insight into the use of decellularized tissues and their applications in skeletal muscle engineering.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Doctoral

Discipline thesis:degree_discipline

Engineering

Grantor

Rice University

Year dc:date.issued

2021

Author dc:creator

• Smoak, Mollie M

Advisor dc:contributor.advisor

• Mikos, Antonios G.

• skeletal muscle engineering
• electrospun scaffold
• skeletal muscle dECM
• volumetric muscle loss

Statement dc:rights

• Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1911/111242

OAI identifier oai:identifier

oai:repository.rice.edu:1911/111242