Document Type
Dissertation
Date of Award
8-31-2018
Degree Name
Doctor of Philosophy in Biomedical Engineering - (Ph.D.)
Department
Biomedical Engineering
First Advisor
Treena Livingston Arinzeh
Second Advisor
George Collins
Third Advisor
Bryan J. Pfister
Fourth Advisor
Pranela Rameshwar
Fifth Advisor
J. Christopher Fritton
Abstract
Articular cartilage has limited healing and self-repair capability due to the absence of vasculature, lymphatic vessels, and nerves. Damage to articular cartilage becomes irreversible leading to formation of osteoarthritis that could severely degrade a person's quality of life. Approximately, 5-10% of cartilage tissue is made up of glycosaminoglycans (GAG), which sequester growth factors as well as provide structural integrity to the native cartilage tissue. Transforming growth factor-beta3 (TGF-β3) is an important growth factor for inducing chondrogenesis in mesenchymal stem cells (MSCs). Bioavailability of TGF-β3 plays a critical role in cartilage repair both in vitro and in vivo. This study evaluates the chondrogenic differentiation of MSCs on scaffolds that contain cellulose sulfate, a GAG mimetic derived from cellulose, in vitro. Since the level of sulfation in GAGs can play a role in growth factor binding, two degrees of sulfation are evaluated, partially sulfated cellulose (pSC) and fully sulfated cellulose (NaCS). Comparisons are made with scaffolds containing native GAGs. Scaffolds are prepared by electrospinning gelatin with cellulose sulfate or the native GAGs and are crosslinked using EDC-NHS chemistry. All scaffolds consist of fibers having average diameters of approximately 3 gm and inter-fiber spacing of approximately 30 gm. TGF-β3 is loaded onto all scaffolds with no statistical differences in the amount of TGF-β3 detected between groups. In in vitro studies, all scaffolds support cell growth. By day 28, cells on scaffolds loaded with TGF-β3 show enhanced expression of cartilage markers, sulfated GAGs, and collagen type II, in comparison to media supplemented TGF-β3. Cells on scaffolds with NaCS and native GAGs loaded with TGF-β3 express similar amounts of GAG and collagen type II. However, lower amounts of collagen type I are expressed by cells on both pSC and NaCS scaffolds as compared to scaffolds containing native GAGs, demonstrating a more homogeneous cartilage matrix produced on the pSC and NaCS containing scaffolds. Gene expression for collagen type II, aggrecan, sox9 and chondroadherin also is expressed at high levels for cells on NaCS containing scaffolds loaded with TGF-β3 by day 14. Lower expression of the hypertrophic markers, collagen type X and VEGF, is seen for cells on all scaffolds loaded with TGF-β3 with the least expression on NaCS containing scaffolds by day 28 in comparison to scaffolds in media supplemented TGF-β3 controls. NaCS containing scaffolds also has the greatest binding affinity for TGF-β3 in comparison to all other scaffolds. MSC chondrogenic differentiation also is examined on pSC and NaCS containing scaffolds in a dynamic compression bioreactor to mimic physiological loading conditions. Findings demonstrates a more homogeneous cartilage-like matrix produced for cells on NaCS containing scaffolds. Therefore, these studies demonstrate that loading TGF-β3 on the scaffolds containing cellulose sulfate enhances MSC chondrogenic differentiation and may be a viable approach for enhancing cartilage tissue regeneration.
Recommended Citation
Menezes, Roseline Dominic, "Cellulose-derived glycosaminoglycan mimetic for use in cartilage tissue engineering strategies" (2018). Dissertations. 1871.
https://digitalcommons.njit.edu/dissertations/1871
Included in
Biomedical Engineering and Bioengineering Commons, Materials Science and Engineering Commons
