Induction of immunity by antigen-presenting cells (dendritic cells) modified by peptides and/or genes

使用从与法师-3衍生的HLA-A2结合肽（FLWGPRALV，氨基酸271-279）脉冲的树突状细胞共培养诱导的特异性细胞毒性T细胞系，我们检查了T细胞受体库用于识别肿瘤抗原衍生肽的用途。我们证明了这些CTL细胞系中TCR Vβ3和Vβ7的寡克隆库。为了在体内用AxCALacZ（作为模型肿瘤抗原）基因转导的树突状细胞诱导特异性免疫，我们使用了针对β-半乳糖苷酶衍生的β-H-2L-d-结合肽（TPHPPARIGL，氨基酸876-884）的辅助性Th 1免疫（产生干扰素-γ和产生IgG 2a）。使用这些针对模型肿瘤抗原的特异性免疫的指标，我们分析了用GM-CSF或白细胞介素-3培养的小鼠骨髓树突状细胞的免疫诱导的差异。此外，我们研究了与阳离子脂质体和肿瘤来源的信使RNA（mRNA）共培养的树突状细胞的肿瘤特异性免疫。分析用pCAGLacZ和肿瘤来源mRNA的p53突变的树突状细胞的转染效率，我们显示10%的效率和增加的p53蛋白表达。经肿瘤mRNA修饰的树突状细胞在荷瘤小鼠体内可诱导特异性保护性免疫，延长荷瘤小鼠的生存期。为了阐明肿瘤免疫的体内诱导，我们正在研究化疗后树突状细胞的抗原摄取和体内运输。另一方面，肿瘤和/或荷瘤宿主的免疫抑制机制（包括Fas配体和TRAIL）的研究也在不断深入，为树突状细胞肿瘤特异性疫苗治疗的临床应用提供了更深入的研究。

Using specific cytotoxic T cell lines induced from cocultured with MAGE-3-derived ＆ HLA-A2-binding peptide (FLWGPRALV, amino acids 271-279) -pulsed dendritic cells, we examined the usage of T cell receptor repertoire for recognition of tumor-antigen-derived peptide. We demonstrated the oligoclonal repertoires of TCR Vβ3 and Vβ7 from these CTL lines. For induction of specific immunity with AxCALacZ (as a model tumor antigen) gene-transduced dendritic cells in vivo, we used the helper Th1 immunity (interferon-γ-production and IgG2a production) against β-galactosidase-derived ＆ H-2L^d-binding peptide (TPHPARIGL, amino acids 876-884). Using indicators of these specific immunity against model tumor antigen, we are analysing differences of immune induction with GM-CSF- or interleukin-3-cultured dendritic cells from murine bone marrow. Moreover, we examined tumor-specific immunity by denditic cells cocultured with cationic liposome and tumor-derived messenger RNA (mRNA). Analysing transfection efficiency of dendritic cells with pCAGLacZ and p53 mutation of tumor-derived mRNA, we showed 10% efficiency and increased expression of p53 protein. And in vivo administration of dendritic cells modified by tumor-derived mRNA demonstratted the induction of specific protection immunity and survival prolongation of tumor-bearing mice. For elucidation of in vivo induction of tumor immunity, we are investigating the antigen-uptake and in vivo traffic of dendritic cells after chemotherapy. On the other hand, we are studying the mechanisms of immunosuppression derived from tumor and/or tumor-bearing host including Fas ligand and TRAIL.For clinical applications of tumor-specific vaccine therapy with dendritic cells, we need to investigate tumor immunity in more details.