An In Vitro Wound Healing Model Evaluating Zinc Supplementation with Synthetic Wound Dressings
Open Access
- Author:
- Snow, Emily
- Area of Honors:
- Biomedical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Justin Lee Brown, Thesis Supervisor
Justin Lee Brown, Thesis Honors Advisor
Peter Butler, Faculty Reader
Maria Rita Castro, Faculty Reader - Keywords:
- Wound Healing
Tissue Engineering
Stem Cells
Zinc
Nutrient Supplementation
Nanofiber Scaffolds
HEK293
Cell Proliferation
Cytokine Secretion
Cell Migration - Abstract:
- The relatively new and expanding field of tissue engineering allows for a vast array of applications, by isolating highly regenerative stem cell lines to use for in vitro studies of differentiation, cell migration, cell-to-surface interactions, and cell environment analyses. This field provides ample opportunity to develop novel strategies and therapies for wound healing Previous research has investigated various scaffolds for wound healing and tissue engineering, with nanofiber scaffolds providing a favorable growth framework and topography which mimics the native extracellular matrix (ECM). Randomly oriented, electrospun polymethyl methacrylate (PMMA) nanofibers served as the primary cell scaffold for this set of experiments to guide cell surface adhesion and migration. This thesis focuses in on wound healing and evaluation of the cell microenvironment following supplementation of a crucial micronutrient, zinc (Zn), which acts as a cofactor for over 200 enzymatic reactions in the body. The treatment groups were supplementation of a low concentration, 1uM, and high concentration, 5uM, of aqueous ZnCl2 and tests of cell proliferation, cytokine secretion, and migration velocity were performed and analyzed. It was found that supplementation of ZnCl2 supplementation of both low and high concentration did not result in a significant increase or decrease in cell proliferation using a PicoGreen assay when compared with a control media. ZnCl2 supplementation of a 1 uM concentration did result in a larger reduction of secretion of specific zinc-mediated, pro-inflammatory cytokines than the 5 uM concentration, namely IL-6, IFN-gamma, IL-1beta, TNF-alpha, and IL-2. The higher zinc concentration, conversely, elicited an increase in secretion of IL-6 and IL-1beta, specifically. When zinc was supplemented directly following a wounding of the cell monolayer, the lower concentration of 1 uM led to a significantly greater cell migration velocity for directed wound closure than the control or 5 uM zinc treatment. The conclusions of this study add to the general body of research surrounding the impact of zinc on endothelial cells in vitro for further understanding of its therapeutic potential to downregulate the aggravated immune response in chronic wound healing.