Analysis of three dimensional architecture of thymic epithelial cells by the multicolor lineage tracing method

胸腺是培养T淋巴细胞祖细胞的器官。皮质和髓质胸腺上皮细胞负责T淋巴细胞教育。我们利用免疫缺陷模型小鼠研究了胸腺上皮细胞三维结构的意义。但到目前为止，在模型小鼠中未发现异常。我的合作者Hiroo Ueno发现一些胸腺上皮细胞在发育过程中发生细胞融合。因此，我们在本研究中测试了胸腺上皮细胞在骨髓移植后或在生理条件下通过联体共生进行细胞融合。然而，没有检测到细胞融合。细胞融合在发育过程中的意义正在研究中，我们还发展了一种新的异基因造血干细胞移植（allo-HSCT）方法，即异基因造血干细胞移植+胸腺移植（allo-HSCT + thymus transplantation，TT）。这种方法在治疗几种传统方法无效的疑难杂症方面是有效的。

Thymus is an organ in which progenitors for T lymphocytes are educated. Cortical and medullary thymic epithelial cells are responsible for T lymphocyte education. We have investigated the significance of 3-D architecture of thymic epithelial cells by using immunodeficiency model mice. However, so far, no abnormality has been found in the model mice. My collaborator, Hiroo Ueno has found that some of thymic epithelial cells undergo cell fusion during development. Therefore, we have tested in this study if thymic epithelial cells undergo cell fusion after bone marrow transplantation, or in a physiological condition by parabiosis. However, no cell fusion was detected. The significance of cell fusion during development is now under investigation.We have also developed a new allo-hematopoietic stem cell transplantation (HSCT) method, allo-HSCT + thymus transplantation (TT). This method is effective in the treatment of several intractable diseases, for which conventions are ineffective.