From Stem Cells to Tissue Transplants: Dynamic Morphology and Quantitative Phase Imaging Diagnostic

Stem cells appear to have the capability of regenerating all cell types in the human body.  Moreover, simple tissue structures generated by culturing these cells have been grown in vitro, suggesting the possibility of regenerating damaged, degenerated, or otherwise dysfunctional organs in vivo.  Stem cells can be harvested from early stage embryos (embryonic stem cells, ESCs) or by inducing changes in the biochemistry of a mature cell (induced pluripotent stem cells, IPSCs). Thus a patient can potentially provide his or her own 'starting material' for organ replacement. Although stem cells have the potential for creating a whole new field of regenerative medicine, their therapeutic implementation will require a new series of diagnostic procedures to ensure that the transplanted ESCs or IPSCs differentiate into the target tissue, engraft normally, and do not develop into tumors. We are working with groups from Stanford Stem Cell Institute, Department of Ob/Gyn, and Bioengineering, with the goal of developing clinical diagnostic procedures enabling the use of ESCs and IPSCs for muscle repair. We employ time lapse, quantitative phase imaging (QPI) methods to measure key properties of stem cells growing in culture prior to transplantation, and have developed automated software methods to extract from the image data a large number of parameters. We are exploring using this data to develop methods for determining safety and efficacy of stem cells by defining normal and tumorigenic ranges for these parameters. QPI allows quantitation of a large number of stem cell properties without using any exogenous staining or genetic manipulation of the cells, a critical feature of any diagnostic procedure, which will most likely be a requirement for measurements on cells destined to be transplanted back into a patient. Stain-free, dynamic quantitative imaging diagnostics will be useful in almost any stem cell therapy procedure.

Speaker: Dr. Thomas Baer, Stanford