The characterization of stem cells from solid tissues is of key importance to regenerative medicine. Our laboratory is working to characterize the epidermal stem cell of the skin. In hematopoesis a quantitative in vivo transplantation assay used in combination with limiting dilution analysis has allowed the determination of a molecular signature for the hematopoetic stem cell. We have designed such an assay for epidermis and are using this assay in combination with limiting dilution analysis to characterize both human and murine epidermal stem cells. We will then work to expand these cells as a potentially superior therapy for burns, wounds, and/or ulcers, as well as effectively targeting a long-lasting cell for gene therapy.
We are also characterizing the tumor initiating cell (cancer stem cell) responsible for the generation of melanoma tumor cells. For these studies we have examined stem cell markers utilized in other tumors, and have obtained an enriched population of melanoma initiating cells from human melanomas. Rather than aiming for bulk tumor destruction, the melanoma initiating cell is the cell we need to target to cure people of this neoplastic condition.