Funding opportunities

Funding Type: 
SEED Grant
Grant Number: 
Principle Investigator: 
Funds requested: 
$363 707
Funding Recommendations: 
Recommended if funds allow
Grant approved: 
Public Abstract: 

Congestive heart failure, the inability of the heart to continue to pump effectively due to damage of its muscle cells, affects approximately 4.8 million Americans and is a leading cause of mortality. Causes of the irreversible damage to the cardiomyocytes that results in congestive heart failure include hypertension, heart attacks, and coronary disease. Because the cadiomyocytes in the adult heart tissue are terminally differentiated and thus cannot regenerate themselves, once they are damaged, they are irreversibly damaged. As a consequence, despite the advances in medical devices and pharmaceuticals, still more than 50% of congestive heart failure patients die within 5 years of initial diagnosis.

The goal therefore must be to restore the heart cells’ functions. This is possible by transplanting fetal and neonatal cardiomyocytes which can then integrate into the host tissue. This approach has demonstrated success in improving heart function. However, the limited availability of fetal donors has prevented its adoption as a viable therapeutic approach.

Embryonic stem cells can overcome this challenge as they proliferate continuously in vitro and can be furthermore stimulated to differentiate. Embryoid bodies are three-dimensional clusters of heterogenous stem cells, some of which contain cardiac myocytes, which demonstrate characteristic spontaneous contractions. Controlled and efficient differentiation of the stem cells into cardiomyocytes and an effective way to characterize/verify these cells is critical. Ensuring a pure population of cardiac myocytes is essential because otherwise there is a high-likelihood of tumor formation when transplanted. Previous studies have shown that a low percentage of all embryoid bodies spontaneously form cardiomyocytes.

Our goal is to therefore develop a self-contained system to grow and controllably differentiate the human embryonic stem cells into cardiomyocytes in high-yields. Few studies have characterized the types of cardiac myocytes in the differentiating human EBs. Our strategy is to use electrical and chemical cues to induce the high-yield differentiation of stem cells into cardiomyocytes and to monitor this process over time both electrically and optically.

Statement of Benefit to California: 

Improvements in differentiating stem cells into homogenous populations of specific cell types are much needed for transplantation therapy in general—and for congestive heart failure patients in particular. The benefits associated with the development of this micro platform have even broader reaching implications beyond biomedical research. After this system is developed, it will serve as a first platform of its kind that can be later commercialized, which would help spur industry growth. To vitalize and enable high-tech/biotech companies to this {REDACTED} area {REDACTED}, engaging industry involvement to this area is necessary. Supporting such activities would furthermore foster the opportunity for student internships with industry and well as afford the students opportunities in entrepreneurship. Our institution is a Hispanic-serving undergraduate institute with almost 50% minority students. Such a proposed system is vital for promoting both the diversity and research culture {REDACTED} and will be leveraged extensively in outreach programs to encourage underrepresented minorities in science education and training. By actively reaching out to specific students who would particularly benefit from our proposed undergraduate internship program, we can attract at-risk students to engage them in research to promote their retention.

Review Summary: 

SYNOPSIS: In this proposal, the PI proposes to induce optimal cardiomyocyte differentiation from hESCs using microsystems wherein ESCs/hEBs are seeded on polymeric scaffolds, allowing rapid exchange in a high throughput fashon of chemical stimuli, tested in combination with electrical and mechanical stimuli, and monitored optically and by electrophysiological measurements. Such variable stimuli may then lead to differentiation to specific subpopulations of cardiomyocytes, including atrial, ventricular and pacemaker cells.

INNOVATION AND SIGNIFICANCE: The creation of cardiomyocytes from hESCs is significant as no other stem cells, perhaps except stem cells within the heart itself, have been proven to differentiate to cardiocytes, and cardiac diseases are a significant health problem in the developing and Western world. The innovative nature of this proposal is to not only use chemical stimuli but also electrical and mechanical stimuli to reach this goal. Although chemical or electrical stimulation have been used individually, detailed studies of combinations of the two types of stimulation are new. A unique microtechnology platform will be used to enable simultaneous differentiation and analysis of multiple embryoid bodies (EB).

STRENGTHS: The proposal addresses an important topic. The investigative team has a strong engineering and electrophysiology background. The proposed research uses an innovative microplatform approach to combine chemical with electrical and mechanical stimuli in a high throughput format to induce specific differentiation from ESCs to different cell types in the heart. The strategy for guiding differentiation is well described. The approach proposed for enriching for cardiomyocytes is convincing and feasible. The platform seems ready for use. It is a clever idea to use a patch clamp on a chip platform for electrical and chemical stimulation of EBs to enhance cardiomyocyte differentiation. The advantages of the proposed system over existing methods of electrical and chemical stimulation is convincing.

WEAKNESSES: Although the investigators provide significant information regarding the possible role of non-chemical stimuli, and although chemical stimuli may aid in cardiac differentiation, very little discussion is given on the exact nature of the factors to be used. To induce specific differentiation, it will likely require that a series of cardiac specific growth factors and cytokines are provided in specific combinations and sequence. Methods for single cell level stripping of cells from EBs seems a bit vague in description and seems challenging to accomplish.

DISCUSSION: The PI previously developed an interesting microfluidic device for patch clamp measurements and now proposes a variation on this as a platform for chemical, electrical and mechanical stimulation of hESC/EB to differentiate them into cardiomyocytes. This is a clever use of previously developed technology. There was discussion as to whether EBs were a feasible cell type for this use with agreement that they could be appropriate. There was a question over whether the fully differentiated cardiomyocytes would be clinically useful, and it appears that in mouse the answer is yes, and thus possibly could be useful in humans as a patch or as single cells.