FUNDAMENTALS AND APPLICATION OF 3D SUSPENSION BATH BIOPRINTING FOR THE ENGINEERING OF MENISCAL TISSUE

Loading...
Thumbnail Image
Degree type
Doctor of Philosophy (PhD)
Graduate group
Bioengineering
Discipline
Engineering
Subject
alignment
anisotropy
bioprinting
computational modeling
meniscus
microfibers
Funder
Grant number
License
Copyright date
2022
Distributor
Related resources
Author
Prendergast, Margaret, E
Contributor
Abstract

Due to limited intrinsic healing capacity, meniscus injuries pose a significant clinical challenge. The most common method for treatment of damaged meniscal tissues, meniscectomy, leads to improper loading within the knee joint, which can increase the risk of osteoarthritis. Thus, there is a clinical need for the development of constructs for meniscal repair that better replicate meniscal tissue organization to improve load distributions and function over time. Advanced 3D bioprinting technologies such as suspension bath bioprinting provide some key advantages, such as the ability to support the fabrication of complex structures using non-viscous bioinks. However, these approaches can be difficult to implement due to complex characterization processes. In this work, the suspension bath bioprinting process is characterized through theoretical and experimental analyses. The impact of suspension bath type and concentration, ink type and concentration, and print speed on printing accuracy, are investigated to guide the optimization of print parameters for future applications. Next, the suspension bath printing process is utilized to print anisotropic constructs with a unique bioink that contains embedded hydrogel fibers that align via shear stresses during printing to guide cell alignment. Microfibers are formed through mechanical fragmentation of electrospun hydrogel and subsequently embedded with cells in cell-degradable gelatin methacrylamide (GelMA) bioinks. Fibers align in the direction of filament deposition during extrusion printing while maintaining high cell viability (>90%). Over a 7-day culture period, meniscal fibrochondrocytes (MFCs) degrade the bioink and align in the direction of fibers, which was not observed in non-printed constructs or printed constructs without fibers. Finally, this anisotropic printing approach is further explored for meniscal tissue engineering in vitro, using MFCs printed within GelMA bioinks. Constructs with and without fibers are printed via a suspension bath bioprinting process and then cultured for up to 56 days in vitro in a custom clamping system. Printed constructs with fibers demonstrate increased cell and collagen alignment, as well as enhanced tensile moduli when compared to constructs printed without fibers. This work enhances our overall understanding of suspension bath bioprinting for tissue engineering and takes a first step in the fabrication of anisotropic constructs for meniscus repair.

Advisor
Burdick, Jason, A.
Date of degree
2022
Date Range for Data Collection (Start Date)
Date Range for Data Collection (End Date)
Digital Object Identifier
Series name and number
Volume number
Issue number
Publisher
Publisher DOI
Journal Issue
Comments
Recommended citation