Characterization of the Effects of bFGF and GSK3β Inhibitors on Embryoid Bodies Derived from Human Pluripotent Stem Cells

<p>Embryoid body (EB) formation is a common first step in many human pluripotent stem cell (hPSC) differentiation protocols. Previous work suggests that EBs are sensitive to growth factor withdrawal if they are derived from hPSCs maintained in feeder independent media such as mTeSR1. To promote cell survival, EBs generated from mTeSR1-adapted hPSCs are sometimes cultured in a medium that contains basic fibroblast growth factor (bFGF), a trophic factor often used in hPSC cultures to maintain self-renewal. This distinguishes feeder independent hPSCs from feeder dependent hPSCs. The purpose of this study was to characterize the effects of bFGF as well as small molecule inhibitors of GSK3β on the formation, growth, cell-cell signaling and early fate decisions of human EBs. bFGF or GSK3β inhibitor treated EBs grew in size and showed evidence of cell proliferation. Control EBs that were fed only a basal serum free EB medium without added growth factors tended to fall apart in culture, adopted irregular morphologies and showed no signs of growth or proliferation. Changes in cell-cell adhesion commonly observed in differentiating hPSCs were apparent in the bFGF and BIO treated EBs, while untreated control EBs predominantly expressed E-cadherin, a cell-cell adhesion molecule highly expressed in undifferentiated hPSCs. Expression of pluripotency markers decreased in all EB groups, regardless of treatment, and increased germ layer marker expression was detected in all groups, with a particular bias towards neuroectoderm. Our results suggest a role for GSK3β in the development and survival of EBs derived from feeder independent hPSCs. These results could inform the development of protocols for the directed differentiation of feeder independent hPSCs using defined media and small molecules.</p>

Name thesis:degree_name

Master of Science in Biomedical Engineering (MSBME)

Level thesis:degree_level

Thesis

Year dc:date.available

2015

Author dc:creator

• Earls, Jonathan

Advisor dc:contributor.advisor

• Ye, Kaiming

Contributors dc:contributor

• Jin, Sha
• Beitle, Robert R. Jr.

• Biological sciences
• Applied sciences
• Molecular Biology

Repository record dc:identifier

https://scholarworks.uark.edu/etd/1236

OAI identifier oai:identifier

oai:scholarworks.uark.edu:etd-2235