인간배아줄기세포와 기형종: 전분화능의 증거와 조직공학 리서치 툴로서의 가치

Abstract

Human embryonic stem cells (hESCs) and recently introduced induced pluripotent stem cells (iPSCs) are stem cells with an indefinite self-renewal and the potential to generate any mature cell type. Because of these properties, pluripotent stem cells hold great promise for regenerative medicine. One of the critical issues, however, is the risk of teratoma formation after transplantation of derivatives of these pluriopotent stem cells. Experimentally, transplantation of hESC and iPS cells into immunodeificient animal led to the formation of tumors composed of all three germ layers, i.e. teratoma. This property is considered the gold standard for demonstrating pluripotency of a given cell type. At the same time, the same type of assay hold promise as a standard for assessing safety of the therapeutic cells intended for clinical applications. This review article describes the key aspects of pluripotent stem cellderived teratoma formation and utilization of teratoma as a research tool for human embryonic development or disease pathogenesis. The promises and limitations of current ES cell-based therapy are also discussed.