Tools and Technologies I
Statement of Benefit to California:
This proposal is focused on the development of multimodal imaging technology combining magnetic resonance (MR) with single photon emission tomography (SPECT). The Principal Investigator (PI) proposes to construct the system, evaluate its performance ex vivo with physical phantoms and then in vivo. Although this system is intended for tracking transplanted cells in living small animals, it can be modified for tracking transplanted stem cells in large animals and humans. The reviewers were enthusiastic about the impact this novel technology could have on stem cell research. They believed the project to be feasible and were impressed by the quality of the preliminary data. Reviewers praised the research team and found it well qualified to carry out the work described in the proposal. The reviewers agreed that this proposal could have a broad impact in the field. Successful stem cell-based therapies will require that transplanted cells be followed in vivo using non-invasive means, first in animal models and then in human subjects. Current imaging technologies suffer from a lack of sensitivity or a lack of spatial resolution. This proposal addresses those problems by building a system that combines an imaging modality offering high spatial resolution (MR) with one offering high specificity (SPECT). Reviewers disagreed about how easily this new technology would translate to humans, with one praising the potential for translation and another wondering whether the size limitations of SPECT equipment would present problems. Reviewers also questioned whether the resolution and sensitivity of the MR/SPECT machine would be great enough to track small numbers of migrating, transplanted stem cells in vivo, but still agreed that the technology is worth pursuing as a necessary developmental step toward a clinical device. The reviewers commented that the research plan is well designed, logical and feasible. They appreciated the strong preliminary data including successful combination of MR imaging and positron emission tomography to enable co-registration of 3D data and resolution restoration. One reviewer commented that one of the major challenges is developing an MR compatible SPECT system, toward which the team has already done much of the work. This reviewer also appreciated that the group will report quantitative performance parameters in evaluating their machine. The reviewers did mention a couple of weakness in the research plan. One noted that no pitfalls, alternative approaches or contingency plans were discussed. Another commented that the proposal would be more exciting if it included in vivo imaging of labeled stem cells rather than just phantoms. The reviewers were enthusiastic about the applicant and assembled research team, noting that they are experts in MR and SPECT imaging and well qualified to carry out the work proposed. Overall, this proposal describes the development of an innovative technology to address a major roadblock in the field of stem cell biology, the ability to track cells after transplantation. Reviewers praised the research plan and the strong team assembled to conduct it.