Employing mineralized collagen scaffolds in a patient-centric approach for improved craniomaxillofacial bone repair

Kolliopoulos, Aliki

Permalink

https://hdl.handle.net/2142/121221 Copy

Description

Title

Employing mineralized collagen scaffolds in a patient-centric approach for improved craniomaxillofacial bone repair

Author(s)

Kolliopoulos, Aliki

Issue Date

2023-07-10

Director of Research (if dissertation) or Advisor (if thesis)

Harley, Brendan A

Doctoral Committee Chair(s)

Harley, Brendan A

Committee Member(s)

• Leckband, Deborah E
• Diao, Ying
• Spiller, Kara

Department of Study

Chemical & Biomolecular Engr

Discipline

Chemical Engineering

Degree Granting Institution

University of Illinois at Urbana-Champaign

Degree Name

Ph.D.

Degree Level

Dissertation

Keyword(s)

• tissue engineering
• regenerative medicine
• biomaterials
• immunomodulatory
• mineralized collagen scaffolds
• macrophage
• mesenchymal stem cell

Abstract

Critical sized craniomaxillofacial defects are a class of bone defects of the skull, neck or jaw that cannot heal naturally by the body, requiring surgical intervention. These types of defects can arise from congenital birth defects such as the cleft palate, cancer resection, and traumatic injuries from high energy impacts such as those in battlefield injuries. Clinical approaches to repair these defects, autografts and allografts, are inadequate due to limited tissue availability and increased risk of disease transmission, respectively. Biomaterials strategies have been developed to regenerate these large-scale defects. Our lab has developed a class of mineralized collagen scaffolds that promote osteogenesis in vitro and mineral deposition in vivo. However, in a recent critical sized in vivo large animal mandibular study we observed poor healing due to increased inflammatory response and poor cell infiltration, osteogenesis, and vascular growth. Thus, there is a need to develop immunomodulatory biomaterials that can direct cell response in a spatiotemporal manner while resolving inflammation and enhancing regeneration. The local wound microenvironment comprises of a highly heterogeneous cell population that constantly undergoes a complex dialogue and is influenced by the local inflammatory state. Understanding the role of these crosstalk interactions and inflammatory state on immune, stem, and endothelial cell response will inform novel biomaterial design approaches for improved repair. Further, this heterogeneity is not limited to the cellular level but extends to the patient level based on characteristics such as sex, age, race, and co-morbidities that influence healing capacity. This thesis focuses on modifying mineralized collagen scaffolds to enhance immunomodulatory properties while employing them as an in vitro platform to understand crosstalk interactions and patient variability. We first describe material changes regarding composition such as the addition of placental derived membranes, or variation of glycosaminoglycan type, and structure by varying pore size and shape, with the goal to improve mesenchymal stem cell immunomodulation and guide immune cell polarization. Further, we elucidate crosstalk interactions between mesenchymal stem cells and immune cells under basal and inflammatory conditions to evaluate the effect of inflammation on cell behavior and crosstalk. Finally, we conducted a comprehensive study of donor variability within our materials with the goal of discerning the effect of sex on mesenchymal stem cell osteogenic response while probing the influence of female sex hormones on stem cell regenerative capacity. Overall, this dissertation describes material changes that can provide local immunomodulation while illuminating opportunities for biomaterial development via the understanding of multi-cell interactions and patient heterogeneity.

Graduation Semester

2023-08

Type of Resource

Thesis

Copyright and License Information

© 2023 Vasiliki K. Kolliopoulos. All rights reserved.

Owning Collections