To realize the full potential of human embryonic stem cells (hESCs), it will be critical to not only understand, but also control the highly orchestrated combinatorial and temporally restricted sequence of signals that direct their differentiation into specific tissues or tissue progenitors. Our understanding of the fundamental processes driving stem cell tissue specific differentiation remain in its infancy and current, empirically developed, techniques yield heterogenous cell populations. New technologies that can enable researchers to efficiently screen multiple conditions affecting growth and differentiation, as well as identify and select individual cells or colonies, would be a great benefit to understanding stem cell biology, and would greatly accelerate the development of methods to prepare stem cell progeny populations for use in regenerative medicine applications. We propose to develop a single platform technology that enables (1) rapid imaging and sorting of adherent hESC and progeny colonies, (2) high throughput studies of hESC growth conditions, and (3) automated, high volume culturing of cells. This will be built on work already developed by this team in micro/nanotechnology and instrumentation for cell biology.
This project will employ three key technologies. The first technology, the micropallet array, is an array very small plastic pedestals on a glass (1" x 3") slide that permits individual stem cells to be grown in a pre-indexed location, allowing researchers to watch a colony develop over time using manual or automated imaging systems, while performing chemical or labeling experiments to identify the characteristics of each progeny population. Specific cells or groups of cells can then be selected and safely removed from the array for further study. This "sorting" capability is extremely powerful for stem cell research, and cannot be done by any method to date.
The second technology, a superimposed microfluidic system to produce multiple growth conditions on a single micro-array slide. This technology uses "laminar flow" to produce parallel streams of growth media, each containing different kinds and amounts of signals. By including all the stem cells together in a single cassette and controlling the local medium around each cell, one can study the effects of micro-environment. Cells will grow close enough to communicate and share extra cellular chemistries, however, neighboring cells will be subjected to different stimuli in the form of chemical compositions in their media.
The third technology will be the integration of microelectronics and computer control in the small cell culture cassette. Microelectronics will be used to control the temperature and flow rates of liquid media, as well as to monitor growth conditions and imaging of the plate. This will reduce the footprint necessary for performing stem cell studies, and allow one to perform remote, pre-programmed stem cell growth experiments.
This work will lead to three major benefits to the state of California:
1. Dramatic increase in throughput for stem cell research in California. With this technology development, automated high throughput experiments can be set up for pursuing large scale studies of stem cells. This will enable California researchers, both in academia and industry, to move research from "single researcher at a bench" style, to large scale automated research. The problems of stem cell research are so rich and diverse, that affordable, high volume research technologies will need to be developed.
2. Development of new techniques for studying stem cell differentiation. The technology proposed in this study will enable detailed studies of stem cell development and differentiation that are not possible using conventional technology, thus providing California researchers with key advantages over our out-of-state competitors. The first beneficiaries of this technology will be California scientists in academia and industry, which will advance the state of the art for stem cell research in California.
3. New economic opportunities for California biotech. The new approaches developed in this work will enable the development of new, high value therapies based on stem cell research. In addition, the techniques will provide for a wealth of opportunities for California companies to participate in the research ecosystem. Opportunities include the production of these technologies and their related materials, supplies, etc. for use by research and medical institutions, use of the technologies for developing advanced therapies, and use of these technologies for delivering therapeutic solutions to patients.