Establishment of the anti-tumor immunotherapy using dendritic cells transfected with tumor extracted RNA

在本实验中，将从人结肠癌细胞系中提取的mRNA引入人树突状细胞，并与T淋巴细胞体外共培养，建立了细胞毒性T淋巴细胞。结果表明，该CTL仅选择性杀伤提取了引入RNA的细胞系。并且，在使用脂质体和不使用脂质体的情况下，CTL的诱导效率进行比较，虽然脂质体对CTL的诱导效率进行了评价，但由于其效率较低，没有观察到显著差异。虽然检测了人体手术标本mRNA的回收效率，但据估计，样品固定情况下屈服点受影响较大，mRNA也普遍碎片化。因此，将从这些固定标本中提取的RNA引入树突状细胞似乎并不有效。相反，冷冻样品似乎适合作为这种方法的材料，因为mRNA在屈服点上丰富，而且碎片也很少。基于目前的研究，我们发现不仅可以从手术样本的大样本中提取mRNA，也可以从活检片等小样本中提取mRNA，可以制作出针对患者肿瘤特异性抗原的树突状细胞疫苗。这些结果表明了树突状细胞治疗的进一步适应性扩展。

In the present examination, it was possible to establish a cytotoxic T lymphocyte by introducing mRNA extracted from human colon cancer cell line into the human dendritic cell, and coculturing with T lymphocyte in in vitro. It was shown that this CTL selectively killed only the cell line from which the introduced RNA was extracted. And, the induction efficiency of CTL, when it was compared in the case in which Liposome was used and case in which it was not used, though it was evaluated of Liposome, as it is efficient a little, no significant difference could be observed. Though the efficiency of the mRNA recovery from the human surgery specimen was examined, the yield point was greatly influenced in fixation situation of samples as estimated, and mRNA was also generally fragmented. Therefore, it seemed not to be effective to introduce RNA extracted from these fixed specimen into dendritic cells. On the contrary, freezing samples seemed to be suitable as a material for this method, since mRNA was abounding on the yield point, and since the fragmentation was also little. Based on the present examination, it was shown that by extracting mRNA not only from large specimen of surgical sample but also from small samples such as the biopsy piece, it is possible to make dendritic cell vaccine which presented the tumor antigens specific to the patient's tumor. These results indicate further adaptation extension of the dendritic cell therapy.