Effective induction of antiglioma cytotoxic T cells by coadministration of heat-induction antigen by means of bio-nanoparticles dendritic cells

由于热诱导颗粒增强树突状细胞（DC）的刺激活性是众所周知的，我们假设在热诱导抗原存在下的DC将通过刺激细胞毒性T细胞而提供特别有效的抗胶质瘤细胞的抗肿瘤活性。作为基础研究，在交变磁场下，用生物纳米颗粒磁铁矿加热大鼠胶质瘤细胞系T-98，使肿瘤细胞周围持续足够浓度的热诱导抗原，然后与同基因骨髓来源的DC和脾脏幼稚T细胞共培养。DC与T细胞共培养后，T-98细胞几乎被完全杀伤，并诱导出较强的肿瘤特异性细胞毒T淋巴细胞（CTL）活性。作为临床前研究，用IL-2和GM-CSF激活从外周血CD 14阳性单核细胞中积累的人DC，并分析培养物中细胞因子水平的表达。在培养物中可以观察到白细胞介素-12和IFN-γ的表达水平显著升高，这可能激活T淋巴细胞。这些结果提示热诱导抗原可通过与T淋巴细胞共培养刺激DCs产生抗胶质瘤的免疫应答，从而发挥其对胶质瘤的杀伤作用。

As it is well known that heat-induction particles enhance the stimulatory activity of dendritic cells (DCs), we hypothesized that DCs in the presence of the heat-induction antigens would provide particularly effective antitumor activity against glioma cells by stimulating cytotoxic T cell. As a fundamental study, a rat glioma cell line T-98 was heated with bio-nano particles, magnetite, under the alternative magnetic field to continue the adequate concentration level of heat-induction antigens around the tumor cells, then cocultured with syngeneic bone marrow-derived DCs and naive splenic T cells. The T-98 cells were almost completely killed cocluture with DCs and T cells, and strong tumor-specific cytotoxic T lymphocyte (CTL) activity was induced. As a pre-clinical study, human DCs accumulated from peripheral blood CD14 positive monocyte was activated with IL-2 and GM-CSF and analyzed the expression of cytokine level in culture. Remarkable elevation of expression level of interleukin-12 and IFN-gamma could be observed in culture which may activate T lymphocytes. These result suggest that heat-induction antigen would stimulate DCs and induce antitumor immunity against glioma by coculturing with T lymphocytes which may act as displaying lytic activity against glioma.