Research: Human embryonic stem cells

Hydrogels for stem cell culture, growth, and differentiation (Ying Li)

Phase contrast image of a hESC colony.

Human embryonic stem cells (hESCs) are being studied as a possible source of cells for the treatment for many diseases (e.g. diabetes, Parkinson’s, leukemia). However, it is difficult to control the maintenance of hESCs, since conditions for self-renewal are incompletely understood. As such, hESCs are typically grown on a feeder layer of mouse cells (i.e., irradiated but viable cells) and are considered xenografts and cannot be used clinically.

Control of hESCs growth and differentiation on a synthetic system offers several advantages. If hESCs can be derived and maintained on the synthetic hydrogel system, it may be possible to eliminate pathogen transmission associated with mouse or human feeder layers. Also, the hydrogel system can increase the reproducibility of culture conditions and elucidate the requirements for hESC maintenance. The goal of our project is to grow hESCs on a hydrogel consisting of loosely crosslinked poly(N-isopropylacrylamide-co-acrylic acid) (p(NIPAAm-co-AAc)). In addition, a semi-interpenetrating polymer network was synthesized by the addition of polyacrylic acid-graft-RGD (p(AAc)-g-RGD) to provide cell binding domains.

Ying Meng's research (Ying Meng)

Coming soon!

Cell adhesion proteins for stem cell culture (Lauren Miller)

Human embryonic stem cells (hESCs) have a great potential for use in tissue regeneration since they can differentiate into cells in all three tissue layers. Our lab has created several surfaces to place these cells on for implantation or injection at the site of injury. The hESCs can attach to these surfaces via a 15 amino acid peptide, from rat bone sialoprotein, containing an Arginine-Glycine-Aspartic Acid (RGD) sequence. RGD sequences are known to give signals to cells via integrins, a type of cellular receptor. The goal of my project is to find new candidate peptides to use on our surfaces through a bacterial peptide display library selection. Once I have candidate peptides, I will assess their ability to bind to the hESCs and encourage self-renewal of these cells on our surfaces.