David C. Sotto

Ph.D. Defense Presentation

Friday, February 27, 2015 
11:00 AM EST

Georgia Tech

Klaus 1116 East

COMMITTEE:

Gang Bao, Ph.D. (Advisor)

Michelle Dawson, Ph.D.

Raphael Lee, M.D., Sc.D. (University of Chicago) 
Todd Sulchek, Ph.D.
Johnna Temenoff, Ph.D.

Title: Directing the Migration of Mesenchymal Stem Cells and Bystander Cells using Superparamagnetic Iron Oxide Nanoparticles

Abstract: Cell migration plays an important role in numerous normal and pathological processes. The physical mechanisms of adhesion, protrusion/extension, contractions, and polarization can regulate cell migration speed, persistence time, and downstream effects in paracrine and endocrine signaling. Methods for understanding these biophysical and biochemical responses to date have been limited to the use of external forces acting on mechanotransductive receptors. Additionally, as the use of magnetic nanoparticles for cell tracking and cell manipulation studies continues to gain popularity, so does the importance of understanding the cellular response to mechanical forces caused by these magnetic systems.

This thesis work utilizes superparamagnetic iron oxide nanoparticles and static magnets to induce an endogenous magnetic force on the cell membrane. This cell manipulation model is used to better understand the mechanobiologal responses of mesenchymal stem cell to SPIO labeling and endogenous force generation. Directionally persistent motility, cytoskeletal reorganization, and altered pro-migratory cytokine secretion is reported in this thesis as a response to SPIO based cell manipulation.