The development of immuno-modulation therapy by use of ES cell-derived dendritic cells

在之前的研究中，我们开发了一种从小鼠胚胎干细胞（ES）生成树突状细胞（DC）的方法。ES-DC的遗传修饰可以很容易地通过转染胚胎干细胞并随后将其分化为DC来完成。在这个研究期间，我们进行了以下项目。用表达DC抗原和T细胞吸引趋化因子的es - dcimmunotherapy，对表达抗原的肿瘤细胞提供了比单独抗原更有效的保护。我们证明ES-DC抗肿瘤免疫治疗即使在同种异体受体小鼠中也是有效的，如果ES-DC和小鼠共享一些MHC等位基因。ES-DC表达Glypican-3（一种最近发现的癌胎抗原），诱导对高转移性小鼠黑色素瘤B16-F10的保护性免疫。ES-DC表达抗原和免疫抑制分子，试图建立一种抗原特异性下调免疫应答的方法。我们证明，用双转染ES-DC处理的小鼠髓鞘少突胶质细胞糖蛋白（MOG）肽诱导的实验性自身免疫性脑脊髓炎（EAE）的严重程度降低，在MHC II类分子的背景下呈现髓鞘少突胶质细胞糖蛋白（MOG）肽，同时表达tnf相关的凋亡诱导配体（TRAIL）或程序性死亡-1配体（PD-L1）。此外，我们获得了几条证据，表明调节性T细胞参与了表达TRAIL的ES-DC诱导的疾病预防作用。从灵长类胚胎干细胞中生成ES-DC为了该技术的未来临床应用，有必要开发一种从人类胚胎干细胞中生成DC的方法。在使用人类胚胎干细胞之前，我们建立了一种从食蟹猴胚胎干细胞系生成ES- dc的方法，该方法在许多方面与人类胚胎干细胞相似。

In the previous study, we developed a method to generate dendritic cells (DC) from mouse embryonic stem (ES) cells (ES-DC). Genetic modification of ES-DC can readily be done by transfection of ES cells and subsequent their differentiation to DC. In this research period, we carried out the following projects.Anti-tumor immunotherapy by ES-DCImmunization with DC expressing antigen plus T cell-attracting chemokines provided protection from antigen-expressing tumor cells more potently than that with antigen only. We demonstrated that anti-tumor immunotherapy with ES-DC was effective even in the allogeneic recipient mice, if some of MHC alleles were shared by the ES-DC and the mice. ES-DC expressing Glypican-3, a recently identified oncofetal antigen, induced protective immunity against highly metastatic mouse melanoma, B16-F10.Antigen-specific down-modulation of immune response by ES-DCWe tried to establish a method for antigen-specific down-modulation of immune response by ES-DC expressing antigen along with immuno-suppressive molecules. We demonstrated that severity of myelin oligodendrocyte glycoprotein (MOG) peptide-induced experimental autoimmune encephalomyelitis (EAE) was reduced in mice treated with the double-transfectant ES-DC, presenting myelin oligodendrocyte glycoprotein (MOG) peptide in the context of MHC class II molecules and simultaneously expressing TNF-related apoptosis-inducing ligand (TRAIL) or Programmed Death-1 ligand (PD-L1). In addition, we obtained several lines of evidence showing that regulatory T cells were involved in the disease-preventive effect induced by ES-DC expressing TRAIL.Generation of ES-DC form primate ES cellsFor future clinical applications of this technology, it is necessary to develop a method to generate DC from human ES cells. Before we use human ES cells, we established a method to generate ES-DC from a cynomolgus monkey ES cell line, which is similar in many aspects to human ES cells.