High Throughput for Small Molecule Probes of hESC Pluriopotency

Funding Type: 
SEED Grant
Grant Number: 
ICOC Funds Committed: 
Public Abstract: 

The key advantage of human embryonic stem cells (hESCs) is that they are pluripotent, meaning that they can be induced to develop into many if not all of the tissues in the body. This property makes them ideal for research into methods of tissue development and regeneration after injury, and will be key for efficient growth of the large quantities of cells that will be needed for broad patient access to forthcoming stem cell therapies. However, hESC culture requires laborious maintenance procedures to avoid spontaneous differentiation into fibroblast-like cells that exhibit loss of this key property of pluripotency. Culture additives, such as bFGF, are currently used to maintain pluripotency, but are only partially effective; thus, there is a substantial need for increased understanding of the pathways that maintain the stem cell state. The goal of this CIRM SEED application is to develop and implement a screen to identify novel small molecule probes of the pathways that maintain hESC pluripotency. The newly discovered probes themselves, or the new cellular pathway information, will lead to more efficient stem cell growth for research into treatments and for implementation of those treatments once they become available.

{REDACTED} has made substantial infrastructure and personnel investment in high throughput screening of drug-like molecules for biological activities, including identification of molecules that promote stem cell functions such as pluripotency and directed differentiation into clinically important tissues. Prior studies in our lab have shown that it is feasible to screen large drug libraries for compounds that maintain pluripotency in hESCs. This proposal is to carry out a screen and to chemically optimize the hits so that they can be used as reagents in hESC culture and as probes to identify the genes and proteins in an hESC that confer pluripotency.

The algorithms and procedures that constitute the screening platform and all information about the primary and optimized small molecules will be deposited publicly on PubChem (http://pubchem.ncbi.nlm.nih.gov/) for open access to all. CIRM funding is critical because of the need to give highest priority to follow up on hits that function across multiple hESC lines, including non-NIH registry lines. Most importantly, our screens are robotically automated and CIRM funding allows us to employ the non-NIH lines that have the demonstrated ability to be dispersed to single cells without adversely affecting their performance, a property that makes them amenable to robotic liquid handling.

Statement of Benefit to California: 

This proposal is a multidisciplinary collaboration among stem cell biologists, chemists, and engineers to address a critical problem that limits the widespread use of hESCs in biotech and eventually clinical settings. The importance of the problem and the multidisciplinary approach will lead to benefits for California that include:

1. The results promise insight into the nature of stemness, the essential property of hESCs that permit them to be cultured indefinitely yet retain the ability to form many useful tissues. The insight gained is believed to be required for understanding how to enable large scale replication of stem cells for forthcoming regenerative medicine therapies involving stem cells.

2. Bringing together a diverse set of people (chemists, cell biologists, engineers) to better address a stem cell problem and forge new links in the academic community that will be capable of creating new approaches to stem cell research. These new areas of research will be one of the legacies of the stem cell initiative and they promise to invigorate academic research in other areas as well.

3. The technologies we will develop and implement apply the new discipline of chemical biology to stem cell biology, and the merger promises to spin off new areas of investigation and biotechnology products expected to benefit the practice of medicine and the local economy.

4. Lastly, supporting implementation of the leading edge technologies and collaborations that will contribute key new components to California’s infrastructure, particularly high throughput chemical library screening and hESC culture techniques, that can be brought to bear on other areas of biomedical research, both in stem cell and non-stem cell sciences.