DOI
https://doi.org/10.25772/1V2J-D509
Defense Date
2018
Document Type
Dissertation
Degree Name
Doctor of Philosophy
Department
Biomedical Engineering
First Advisor
Rene Olivares-Navarrete, D.D.S., Ph.D.
Second Advisor
Barbara D. Boyan Ph.D.
Third Advisor
Henry Donahue, Ph.D.
Fourth Advisor
Bruce K. Rubin, M.Engr., M.D., M.B.A., FRCPC
Fifth Advisor
John J. Ryan, Ph.D.
Abstract
Biomaterials are becoming the most commonly used therapeutic method for treatment of lost or damaged tissue in the body. Metallic materials are chosen for high strength orthopaedic and dental applications. Titanium (Ti) implants are highly successful in young, healthy patients with the ability to fully integrate to surrounding tissue. However the main population requiring these corrective treatments will not be healthy or young, therefore further research into material modifications have been started to improve outcomes in compromised patients. The body’s immune system will generate a response to any implanted material, and control the final outcome. Among the first and most influential, cells to interact with the implant will be macrophages. Throughout this study we have 1) established the ability of macrophages to recognize and differentially activate in response to material surface properties, 2) investigated the role of integrin binding in macrophage activation to material properties, and 3) confirmed the importance of macrophage activation in vivo following Ti implant placement. The generation of a hydrophilic implant surface promoted the greatest anti-inflammatory and pro-regenerative macrophage activation. Surface wettability will control protein adsorption which can activated different integrin binding on macrophages and may be responsible for changes in activation. When integrin β3 subunit binding was prevented hydrophilic surfaces no longer promoted an anti-inflammatory macrophage activation. Additionally, when macrophage levels were reduced using two separate ablation models, MaFIA mice and clodronate liposomes, hydrophilic surfaces no longer promoted anti-inflammatory T-cell populations and cytokine profiles. There were also fewer stem cells adhered to implant surfaces at 1, 3, and 7 days when macrophage populations were compromised.
Rights
© The Author
Is Part Of
VCU University Archives
Is Part Of
VCU Theses and Dissertations
Date of Submission
5-11-2018
Included in
Biomaterials Commons, Immunity Commons, Molecular, Cellular, and Tissue Engineering Commons