SBIR Phase I:In vivo Fluorescence Imaging Kit for Cell Proliferation.

This Small Business Innovation Research (SBIR) Phase I project is to apply novel bio-orthogonal tetrazine ligation technology to fluorescent labeling of DNA replication, and to ultimately produce a fluorescence imaging kit (FIK) for cell proliferation. The advantages are two-fold: 1) Because of the novel chemical mechanism, the FIK would allow for in vivo cell imaging, essentially providing continuous observation of cell proliferation with minimal interference from cell metabolism. Fluorescent microscopy could be done with live cells. 2) A single cell could be monitored through various stages of cell cycle. None of the existing methods allow for in vivo imaging of cell proliferation. Thus, conceptually, the difference between the capabilities of the existing assays and proposed FIK assay is analogous to the difference between a snapshot and a video recording. The broader impact/commercial potential of this project is to develop an assay for cell proliferation compatible with high-throughput screening technology. The assay can be applied to differentiate between quiescent and actively cycling stem cells, and, eventually, to differentiate between cancer stem cells and cancer cells. The low cost of reagents, simplicity of sample handling, and readiness to be adapted to a multi-well format make the proposed methodology an ideal candidate for application to high-throughput screening assays that will find applications in the fields of cancer biology and neurogenesis, as well as developmental and molecular biology. These fields all share a common research need for close observation of cell processes.