Imaizumi Mitsuyoshi, Nomoto Yukio, Sugino Takashi, Otsuki Koshi, Omori Koichi
Department of Otolaryngology, School of Medicine, Fukushima Medical University, Japan.
Acta Otolaryngol. 2013 Apr;133(4):405-11. doi: 10.3109/00016489.2012.742566.
The histological findings and quantitative measurements demonstrated that there were differences in teratoma formation according to the site of implantation. Elucidating the mechanisms of the teratoma formation caused by the site of implantation moves the field another step closer to clinical use of induced pluripotent stem (iPS) cells for tracheal regeneration.
Our previous study demonstrated the potential for iPS cells to be used as a new cell source for tracheal regeneration. However, teratoma formation remains a major problem. Implantation site-dependent differences in teratoma formation have been reported. In this study, the teratoma-forming propensity after implantation into tracheal defects and abdominal subcutaneous tissue was examined histologically and quantitatively.
Mouse iPS cells were cultured in artificial material under various conditions. After cultivation in vitro, artificial materials with cultured iPS cells were then implanted into cervical tissue around tracheal defects and into abdominal subcutaneous tissue in nude rats. Teratoma formation was evaluated histologically and quantitatively with measurement of maximum diameter (MD).
Teratoma was observed in 10 of 11 rats with cervical tissue around tracheal defects and in 3 of 11 rats with abdominal subcutaneous tissue implants. The average MD was 5.36 mm in the trachea and 0.97 mm in the abdomen.
组织学研究结果和定量测量表明，根据植入部位不同，畸胎瘤形成存在差异。阐明由植入部位导致畸胎瘤形成的机制，使该领域在诱导多能干细胞（iPS细胞）用于气管再生的临床应用方面又迈进了一步。
我们之前的研究证明了iPS细胞作为气管再生新细胞来源的潜力。然而，畸胎瘤形成仍然是一个主要问题。已有报道称畸胎瘤形成存在植入部位依赖性差异。在本研究中，通过组织学和定量方法检查了植入气管缺损处和腹部皮下组织后形成畸胎瘤的倾向。
将小鼠iPS细胞在各种条件下培养于人工材料中。体外培养后，将含有培养的iPS细胞的人工材料植入裸鼠气管缺损周围的颈部组织和腹部皮下组织。通过测量最大直径（MD）对畸胎瘤形成进行组织学和定量评估。
在11只植入气管缺损周围颈部组织的大鼠中，有10只观察到畸胎瘤形成；在11只植入腹部皮下组织的大鼠中，有3只观察到畸胎瘤形成。气管部位的平均最大直径为5.36毫米，腹部为0.97毫米。
