Biophysical Reprogramming of Pluripotency
Embryonic stem cells are pluripotent (i.e. they can be differentiated into any adult cell type). Recent, major breakthroughs have been made into making adult cells (e.g. fibroblasts from skin) pluripotent (called induced pluripotency). The most successful method in humans involves introducing genes that confer pluripotency. Other methods are the use of proteins or drug-like compounds. However, all of these methods have disadvantages and are not yet safe for human use. Physical stimuli that alter cell function are called biophysical stimuli. These include mechanical manipulation, fluid flow, temperature changes, change in pressure of oxygen, and electromagnetic pulses among others. While it is known that biophysical stimuli can differentiate stem cells into a variety of cell types almost nothing is known about the reverse: i.e whether biophysical stimuli can induce pluripotency or a more stem-like behavior in adult cells. If we can induce pluripotency through biophysical means, several bottlenecks in tissue regeneration, gene therapy and drug discovery can be resolved. Our laboratory already has preliminary results showing electromagnetic pulses, controlled heating, and low oxygen can affect and reverse cell differentiation.
In this proposal we aim to establish the effect of select biophysical stimuli on manipulating cell differentiation states towards a more stem cell-like nature, to identify potential non-genetic mechanisms by which these stimuli may act, and to determine whether these stimuli can enhance existing methods that are used to induce pluripotency. This will be achieved through 3 aims. Aim 1 is to establish the effects of mechanical stimuli, fluid flow and perfusion, electromagnetic fields, hypoxia and controlled heat shock on markers of differentiation in differentiated and undifferentiated embryonic stem cells and adult cells. Aim 2 is to determine how the biophysical stimulation affects the non-genetic regulation of cell differentiation. Aim 3 is to enhance existing methods of reprogramming of cells to become more stem-like by combining biophysical stimuli with genetic factors. Specific biophysical stimuli will be selected to substitute for one or more genetic factors as well as to enhance overall reprogramming efficiency.
Reprogramming of cells through biophysical stimuli will lead to a clinically safer methods of generating stem cell-like cells from adult cells. Reprogramming can be achieved remotely or in situ if non-contact biophysical stimuli such as electromagnetic pulses are effective. Targeting reprogramming of specific cell types or reprogramming of partially differentiated cells may be possible and even desirable since many clinical applications do not require fully pluripotent cells. Our approach may also enhance the efficacy of existing methods of reprogramming or in parallel and in combination could result in more clinically acceptable treatments.
California has been at the forefront of biomedical research for more than 40 years and is internationally recognized as the biotechnology center of the world. The recent debate over the moral and the ethical issues of stem cell research has hampered the progress of scientific discoveries in this field, especially in the US. CIRM is a unique institute that fosters ethical stem cell research in California. CIRM has also serves as an exemplary model for similar programs in other states and countries.
This grant proposal falls under the mission statement of the CIRM for funding innovative research. The proposal will utilize novel techniques for reprogramming of pluripotency in somatic cells. The proposed methods are likely to be increase the clinical safety and enhance the efficiency of current techniques. This proposal will also expand the field in a new direction and integrate multidisciplinary methods. If successful, this will further validate the significance of the CIRM program and will help maintain California's leading position at the cutting edge of biomedical research. Reducing the medical and economic burden of large numbers of patients who will benefit from this technology is of great significance.