Experimental study on the mechanism of immunotherapy in human brain malignant gliomas with dendritic cell vaccine targeting of cancer stem cell in vitro

Abstract

Objective To explore the ability of anti-glioma cells and the mechanism of specific T cells induced by dendritic cells loaded with the antigen of glioma stem cells.Methods The cancer stem cells were cultured from the U251 cell line.The lysate of glioma stem cells was obtained through the repeated freezing and thawing method.Dendritic cells (DCs) were prepared from mouse mesenchymal stem cells.The glioma stem cell vaccine was produced by mixing tumor stem cell lysate with DCs.Then,the surface markers of DCs were checked by flowcytometry.CCK-8 method was used to detect the DC vaccine' s ability of promoting T cells proliferation and killing U251 cells.The level of IFN-γ in the supernatant was checked by ELISA.Dendritic cells pulsed with heat-treated U251 were used as the control group.Results After the stimulation glioma stem cell lysate,the expression of surface molecules of DCs was up-regulated,including CD80(95.10 ± 0.44)％ 、CD86 (92.90 ± 4.85)％ 、CD11C (75.53 ± 0.50)％,and MHC Ⅱ (94.27 ±2.30)％.Compared with control groups,glioma stem cell vaccines could stimulate the proliferation of T cells more strongly,induce more effective immunoresponse against glioma cells(the highest killing rate was (78.508 ±4.156)％ at effector:target ratio 80∶1),and strongly boost the secretion of interferon-γ.Conclusions Dendritic cells pulsed with glioma stem cells' lysate can effectively induce specific cytotoxic T cells,show strong anti-tumor properties,and provide a new potent way for the immunotherapy of human brain malignant gliomas with dendritic cell vaccines. Key words: Glioma; Cancer stem cell; Dendritic cell ; Vaccine