Synthetic Matrices for Stem Cell Growth and Differentiation

Synthetic Matrices for Stem Cell Growth and Differentiation

Funding Type: 
Tools and Technologies I
Grant Number: 
RT1-01053
Award Value: 
$599,404
Stem Cell Use: 
Embryonic Stem Cell
Status: 
Closed
Public Abstract: 
There is a critical need for new technologies to facilitate growth and differentiation of human embryonic stem cells (hESC) using clinically acceptable, animal-free reagents. In particular, most currently used culture conditions are not acceptable for standardized production of clinical grade cell products. We propose to develop novel, well-defined, synthetic extracellular matrices for growth and differentiation of hESC. Our approach is to first understand how hESC interact with extracellular matrix materials by analyzing candidate adhesive substrate proteins and integrin receptors that mediate attachment, survival, proliferation and differentiation. Biomimetic, synthetic matrices will be developed, with components and strategies informed by our knowledge of fundamental cell biology. We have established an active, interdisciplinary collaboration between experts in cell biology, stem cell culture, peptide chemistry and materials research. Preliminary data have identified crucial receptors that mediate adhesion and survival of hESC. As proof of concept, novel, biocompatible hydrogel polymers have been developed and analyzed for physical properties, cellular toxicity, and for their ability to support adhesion and growth of hESC. A method for rapid, high throughput screening of candidate hydrogel peptides has been developed using inkjet printing technology. We propose to develop and test peptide-hydrogels for culture of hESC. Peptides from adhesive extracellular matrix proteins will be screened for their ability to support adhesion, survival, proliferation and differentiation of several hESC lines, including some that are not federally approved. Arrays of candidate materials, using single peptides and combinations of peptides will be arrayed using ink jet printing and assayed in adhesion assays. Larger scale experiments will test adhesive substrates for survival, proliferation, and maintenance of the undifferentiated state. The proposed experiments, if successful, will address an important unmet need in bringing stem cell therapies to the clinic and provide the foundation for a wide range of fundamental studies.
Statement of Benefit to California: 
The State of California, like the rest of the nation, faces immense challenges to its health care system, with soaring medical costs due in part to continuing care of our aging population. The percentage of elderly in California is expected to grow from what was 14 percent in 1990 to 22 percent in 2030. Chronic degenerative diseases such as Alzheimer’s disease, Parkinson’s disease, age-related macular degeneration, cancer, diabetes, cardiovascular disease, osteoarthritis, and osteoporosis afflict a growing number of individuals in California. Major innovative approaches are now, more than ever, an imperative. Human embryonic stem cells (hESC) have great potential for the treatment of disease and injury because they are pluripotent in their capability to form most cell types in the body. They will also be of great utility for screening new drug candidates, and for understanding the molecular mechanisms of human development and disease. However, methods used to grow hESC are in their infancy, and scale up for production of clinical grade cells will require further research. Our proposed research will develop new methods for culture of hESC using synthetic matrices that will be suitable for clinical applications. If successful, this work will be a great benefit to the state by providing useful new technology that addresses a critical need in the field of stem cell research. In addition, it provide new approaches for therapies to treat degenerative conditions that afflict millions of Californians.
Progress Report: 

Year 1

We proposed to develop novel, well-defined, synthetic extracellular matrices that support survival and proliferation of human embryonic stem cells. This is an important, unmet need in the field and development of such a substrate would aid in moving stem cell therapies to the clinic. In the first year of support, we have made significant progress. First, we characterized the cell surface receptors for matrix proteins on stem cells and identified specific proteins that will support adhesion and growth of the cells. Second, using an interdisciplinary approach, we developed a novel method to screen peptides from these proteins for their ability to support adhesion and proliferation of the stem cells. Finally, we identified a cyclic RGD peptide that supports growth of human embryonic stem cells. We are continuing to screen for new peptides that might be combined with cyclic RGD to optimize a scalable, inexpensive, clinically compliant substrate.

Year 2

We proposed to develop novel, well-defined, synthetic extracellular matrices that support survival and proliferation of human embryonic stem cells. This is an important, unmet need in the field and development of such a substrate would aid in moving stem cell therapies to the clinic. In the second year of support, we continued to make significant progress. Based on our characterization of cell surface receptors for matrix proteins on stem cells completed in the first year, we went on to test specific, purified proteins that will support adhesion and growth of the cells. In addition, we examined whether these substrates will support differentiation of retinal pigmented epithelial cells, an important, clinically relevant cell type that is currently in clinical trials for eye disease. Second, using an interdisciplinary approach, we developed novel hydrogels using click chemistry that support adhesion and proliferation of the stem cells. We continued studies of a cyclic RGD peptide that supports growth of human embryonic stem cells. We then went on to test a new synthetic surface containing another RGD peptide developed by collaborators at Geron and Corning. This surface proved to be efficient at supporting growth of undifferentiated hESC as well as differentiation of useful cell types. Thus we have identified two synthetic substrates we believe are scalable, inexpensive, and clinically compliant.

Year 3

We proposed to develop novel, well-defined, synthetic extracellular matrices that support survival and proliferation of human embryonic stem cells. This is an important, unmet need in the field and development of such a substrate would aid in moving stem cell therapies to the clinic. In the second year of support, we continued to make significant progress. Based on our characterization of cell surface receptors for matrix proteins on stem cells completed in the first year, we went on to test specific, purified proteins that will support adhesion and growth of the cells. In addition, we examined whether these substrates will support differentiation of retinal pigmented epithelial cells, an important, clinically relevant cell type that is currently in clinical trials for eye disease. Second, using an interdisciplinary approach, we developed novel hydrogels using click chemistry that support adhesion and proliferation of the stem cells. We continued studies of a cyclic RGD peptide that supports growth of human embryonic stem cells. We then went on to test a new synthetic surface containing another RGD peptide developed by collaborators at Geron and Corning, called synthemax. This surface proved to be efficient at supporting growth of undifferentiated hESC as well as differentiation of useful cell types. We also tested a new liquid version of synthemax. Thus we have identified two synthetic substrates we believe are scalable, inexpensive, and clinically compliant.

© 2013 California Institute for Regenerative Medicine