Award Date

12-1-2014

Degree Type

Thesis

Degree Name

Master of Science (MS)

Department

Dental Medicine

First Committee Member

Karl Kingsley

Second Committee Member

James Mah

Third Committee Member

Cliff Seran

Fourth Committee Member

Rhonda Everett

Fifth Committee Member

Tim Bungum

Sixth Committee Member

Kathryn H. Korgan

Number of Pages

69

Abstract

Mesenchymal stem cells are derived from a variety of human tissues and are being bioengineered and studied for possible uses in the advancement of medicine. Recent efforts are being focused on Dental Pulp Stem Cells (DPSC's) due to the accessibility of this tissue. Many factors influence DPSC quality and quantity, including the specific methods used to isolate, collect, concentrate, and store these isolates once they are removed. Ancillary factors, such as the choice of media, the selection of early versus late passage cells, and cryopreservation techniques may also influence the differentiation potential and proliferative capacity of DPSC isolates.

The objective of this study was to evaluate the potential to induce differentiation of DPSC isolates in vitro by the adding of exogenous growth factors (GF), and by the coating of specific extracellular matrix molecules (ECM) onto the surface of tissue-culture dishes. Photomicroscopy and mRNA analysis demonstrated the addition of TGF-β1 notably increased pluripotency biomarkers in DPSC lines. The addition of Dexamethasone (Dex) or plating on Laminin-5 (LN5) was correlated with changes to cellular morphology and cell size in different subsets of cells. RNA isolated from these DPSCs for relative endpoint (RE) reverse transcription polymerase chain reaction (RT-PCR) revealed mRNA DPSC specific intracellular biomarkers (Klf4, Sox-2, Bin-1, Rnf12, Oct-4 and NANOG) and the cell surface marker (CD133) were enhanced following the administration of TGF- β 1 and were differentially down-regulated following Dexamethasone and Laminin-5 administration. This study provides some initial evidence that randomly selected DPSC isolates may be induced by established protocols to change phenotype and expression of pluripotent biomarkers with variable susceptibility between differing types of DPSCs. More studies will be needed to determine the range of cell types that can be successfully re-engineered in laboratory settings.

Keywords

Cell differentiation; Dental pulp; Dental pulp Stem Cells; Differentiation; Extracellular matrix; Growth factors; Mesenchymal stem cells; Stem cells

Disciplines

Biomechanical Engineering | Biomedical | Biomedical Devices and Instrumentation | Cell and Developmental Biology | Cells | Dentistry

Language

English