虽然同种组织和器官移植已有近半个世纪的历史，但移植后的排斥反应仍是影响成功的最主要问题，也是当今移植界研究的热点。如何有效地诱导免疫耐受，已成为移植免疫学领域的重要课题。20世纪90年代初Starzl发现微嵌合状态，指器官移植以后，用现代细胞学和分子生物学手段观察 Although allografts and organs have been transplanted for nearly half a century, the rejection after transplantation is still the most important issue that affects success. It is also a hot spot in today’s transplant community. How to effectively induce immune tolerance has become an important issue in the field of transplantation immunology. In the early 1990s, Starzl found that the state of microchimerism, after organ transplantation, was observed by means of modern cytology and molecular biology