Tools and Technologies I
Recent developments in stem cell research suggest that the next revolution in medicine might come from cellular therapies. Transplantation of blood cells has already made a significant impact on the treatment of cancer, but until recently it was inconceivable that we will be able to reconstitute injured organs or regenerate functional tissues. However, it will be neither easy nor soon that we will be able to implement stem cell therapies as standard treatments of disease. One of the major limitations is our poor ability to study the behavior of cells within the body, their natural site of operation. Consequently, extensive experimental approaches are being developed to simulate the events that take place in real life, with quite limited success. It is difficult to imagine quality stem cell therapies without the ability to properly monitor these cells in the body, subsequent to introducing them into the patient. For achieving their desired revolutionary treatments, we need to better study the mechanisms and spatiotemporal details of stem cell behavior, within a realistic setting. We know that the most primitive stem and progenitor cells are in a low functional state, and require interaction with their specific environment to initiate, direct and control their activity. We also know that the temporal succession of these processes is of outmost importance, as stem cells will react differently when submitted to different sequences of inductive signals. Collecting these data in vivo is much more difficult than otherwise, but given the complexities involved, it is by far the most relevant and efficient path to better understand the functioning of stem cells within the body, and find ways of optimizing it, for therapies as well as safety. Optical imaging can provide the needed temporal and spatial resolution; however, no commercially available method, no matter how expensive or established, has the requisite performance in vivo. We therefore propose to develop, integrate and use new optical imaging technologies to characterize, in live animals, the behavior of stem cells, down to the molecular level. The needed focus on known molecular interactions, at optimal times requires our new, multimode combination of powerful imaging methods, deployed in concert: hyperspectral (derived from satellite reconnaissance), scattering, fluorescence and coherence, some of which we pioneered. We aim to establish our system as a platform for simultaneous, versatile functional acquisition of information under physiological conditions in real time, to test sequential molecular events in live stem cells, and propose to apply it to investigate important issues, including the interaction of stem cells with their environment, stem cell movement to a specific locus, based on injury or other aberrant physiology, cancer stem cells, and stem-cell based neuroregeneration.
Statement of Benefit to California:
The promise of harnessing stem cells for the treatment of human disease is very exciting, but a lot is required to turn it into reality. Great leaps in technology and in molecular-level understanding of biology are very helpful, but for impacting the way treatments are delivered, more conditions are necessary, strategic, logistic, financial, political. The achievement of true breakthroughs, especially in a massive, heavily regulated field like healthcare, depends on the favorable alignment of a number of circumstances; this is more likely to happen at a state, rather than federal level. To accelerate the pace towards therapies for patients with chronic and debilitating disease and injury, the citizens of California (CA) supported Proposition 71 and the establishment of the CIRM, thus recognizing the fundamental importance of stem cell research to the future of biotechnology and regenerative medicine. The benefits of any research deemed of high-enough quality by CIRM for funding are likely to be scientific, medical, economic and human, as follows: I. General 1. Fostering better, more goal-directed interdisciplinary science in CA 2. Enhancing CA competitiveness and image in the scientific and medical world 3. Accelerating the path to the cure of important, challenging diseases II. CA--specific 1. Addressing - faster, better - problems that are more pronounced in CA (e.g. neurodegenerative diseases, linked to population ageing and overuse of pesticides) 2. Further securing CA’s leading position in biomedical research, biotechnology and potentially in healthcare delivery 3. Attracting relevant research and medical talent to CA 4. Reducing the cost of treating major diseases III. Additionally, our specific in vivo imaging project, if funded, would contribute as follows: 1. Appling efficient, therapy-relevant investigation and validation methods to important cell lines outside the limits of federally-funded research 2. Developing technologies not likely funded by government, for obtaining data critical to the future of the field and to directing the research strategies of CIRM 3. Transferring to CA-based industry of important technologies that will further strengthen CA’s already leading role in the medical device industry, and creating quality jobs (with positive effects on our tax base) 4. Providing a key ingredient for stem cell therapy validation, standardization and optimization, needed for FDA approval of any therapies (as extensive preclinical testing will be required before these cells are approved for use in humans), and thus 5. Shortening the timelines for delivering cell-based therapies to patients Our California-invented technology would allow watching some good cellular therapy scenarios unfold in vivo, at a level of spatiotemporal detail that allows subsequent improvements, but also some negative scenarios (immune rejection, teratomas) in their details, in order to learn how to prevent them.
This proposal focuses on the development of a multimodal imaging system that that is capable of in vivo measurement of a wide variety of cellular and molecular phenomena, a technology that would allow researchers to address fundamental questions in stem cell biology. First, the applicant proposes to assemble a multimodal imaging system into a single rig which will be optimized for performance and adapted to a platform where cellular, molecular, and physiological data can be simultaneously gathered. The applicants point out that these various data types will yield synergistic information when collected from the same cells at the same time. For the remainder of this effort, the applicant will perform proof of concept experiments using the instrument to test multiple hypotheses surrounding stem and progenitor cell engraftment in murine calvaria. Additional validation will be attempted using hair cells and cancer stem cells as models. The reviewers were enthusiastic about the proposed concept of combining multiple technologies. While encouraged by the concept, the considerable technical, practical and budgetary challenges, as well as an overly complex validation strategy, diminished the reviewers’ confidence that the proposed goals would be met. Finally, reviewers noted a potential weakness in the research team that raised questions about the collective ability of the team to capitalize on their findings. The reviewers felt that, in theory, the impact of the proposed technology could be substantial. The ability to study stem cells criteria multiple levels of data resolution in their native environment would provide the opportunity to address long-standing questions in the field. Furthermore, combining multiple components into a single rig would provide practical and logistical advantages to the practicing investigator. However, the reviewers were concerned that the cost and complexity of such a device would preclude its widespread use. Furthermore, the applicant did not adequately address the need for informatics tools that would be necessary to integrate, synthesize and interpret the acquired data. These weaknesses were thought to decrease the overall impact of the proposed technology, even if it were successfully realized as described. The proposal was judged to be dense, difficult to read, and appeared to be a compilation of loosely linked projects, with no real discussion about the potential pitfall in combining the technologies. Reviewers raised many concerns about the practicality of the proposed device, such as the potential of failure in one component to cause cascading generalized failure of the whole system. Some of the strongest criticism was directed towards the scope of the proposed endeavor, particularly with regards to the proof of concept experiments. Some elements of the research design raised red flags, such as the failure to consider gender of the stem cells which will affect engraftment, and the use of quantum dots, which are likely to have toxic effects in vivo. Some reviewers noted a lack of staff dedicated to these investigations, indicating that the applicants might have underestimated the challenges of this approach. Thus, despite some encouraging, but limited preliminary data, the reviewers would have preferred that the applicants focus on a single or smaller set of modalities to evaluate the performance of the instrument before embarking on a complex strategy of biological validation. The reviewers felt that the applicants were well qualified to develop the proposed technology. The principal investigator has the necessary expertise to oversee the assembly of the instrument as well as and direct the biological validation experiments. The multidisciplinary team has the necessary expertise in chemistry, physics, and biology to conduct the proposed experiments. However, the reviewers were unclear as to who would actually build and maintain the instrument. Furthermore, the lack of a computer scientist on the team was viewed as a substantial liability, as the need for data collection, management and integration are essential to realize the full potential of the proposed technology. Overall, the technology described in this proposal could be powerful and practical, but the reviewers were not convinced of its feasibility and therefore, its potential to advance the field.