Gordon Keller
PhD, University of Alberta
Research Synopsis
Lineage Specific Differentiation of Embryonic Stem Cells
The overall goals of our research program are to understand the mechanisms that control mesoderm and endoderm induction and specification in mouse and human embryonic stem (ES) cell cultures. Our studies focus specifically on the generation of the following derivative lineages: hematopoietic, vascular, cardiac, hepatic and pancreatic. Research projects include:
- characterization of the earliest developmental stages of lineage commitment
- identification of the signaling pathways regulating lineage specification and maturation, and
- generation of functional cell populations for transplantation in preclinical models of human disease.
For the mesoderm-derived lineages we have demonstrated that the earliest stages of hematopoietic and cardiac development in ES cell cultures are defined by the appearance of progenitors that display both tissue specific and vascular potential. Within the hematopoietic system, these progenitors are known as hemangioblasts whereas those that define the onset of cardiac development are known as cardiovascular progenitors. Our current studies are aimed at defining the mechanisms that control the proliferation and differentiation of these progenitor populations. The long-term goal of these transplantation studies is to develop new therapies for the treatment of hematopoietic and cardiovascular diseases. With respect to endoderm derivatives, we have shown that the combination of activin A, BMP-4 and bFGF will lead to the efficient generation of cells with characteristics of immature hepatocytes. Modification of this induction protocol results in the development of pancreatic progenitors. Our current research projects in this area are focused on understanding the pathways that regulate the maturation of these populations into functional hepatocytes or insulin-secreting pancreatic beta cells. Access to ES cell-derived hepatocytes and beta cells will provide a novel source of these cells for cell based therapy approaches for the treatment of diabetes and certain types of liver disease.
II. Imaging Clinical Trials
The development of new imaging technologies to improve disease diagnosis, guide therapeutic interventions and monitor response to treatments enables optimal clinical outcomes for patients with cancer and other diseases. We have developed new first-in-class optically-based imaging platforms for intraoperative surgical guidance in (breast) cancer patients and point-of-care imaging of infectious diseases. The DaCosta Lab’s clinical trials group has developed a standardized system for conducting Phase 0-III clinical trials of medical devices and imaging agents under strict Good Clinical Practice policies in close collaboration with Health Canada, institutional regulatory bodies and industry partners. Our interest is to develop next generation imaging technologies that are rapidly translated to first-in-human studies with a longer term vision of commercializing the innovations for broader value to patients and health systems around the world. Currently, our certified clinical trials group is conducting two Phase I-II clinical trials with local and international partners to investigate: 1) intraoperative fluorescence image-guided margin assessment and surgical resection in advanced breast cancer ( Fig. 2 ) and 2) intraoperative fluorescence and photoacoustic imaging of breast and thyroid cancers. We are also conducting five Phase II trials investigating the use of point-of-care optical imaging technologies for detection of bacterial infection in wounds and cancer surgical sites.
Recent Publications
- Gouon-Evans V, Boussemart L, Gadue P, Nierhoff D, Koehler CI, Kubo A, Shafritz DA and Keller G. 2006. BMP-4 is required for hepatic specification of mouse embryonic stem cell-derived definitive endoderm. Nat Biotech. 24:1402-1411
- Kattman SJ, Huber TL and Keller G. 2006. Multipotent flk-1+ cardiovascular progenitor cells give rise to the cardiomyocyte, endothelial, and vascular smooth muscle lineages. Dev Cell. 2006 11: 723-732
Graduate Students
Ian Fernandes
Nestor Fernandez
Gregory Kent
Quynh Nguyen