Effects of dendritic cell vaccines on hematogenous micrometastasis of bladder cancer carrying for PBL-SCID mice

Abstract

To study the effect of dendritic cells loaded with whole tumor antigen on hematogenous micrometastasis of bladder cancer model in hu-PBL-SCID mice. T24-3 cell subset was selected from human bladder transitional cell carcinoma T24 cell line by Boyden chamber system. The SCID mice intraperitoneally injected with 4 × 107 hu-PBL and subcutaneously injected with 3 × 106 T24-3 cells were named hu-PBL-T24-3-SCID model. Human IgG level in the blood plasma of mice was detected by ELISA, and human CD3+, CD4+, CD8+ T cells in blood and spleen cells of mice were detected by FCM analysis for human immune reconstruction study. Human CK20 mRNA expression in mice peripheral blood was detected by RT-PCR to investigate metastasis of tumor cells. The PBMCs were isolated from human peripheral blood, and were induced into DCs by co-culture with rhGM-CSF and rhIL-4 in vitro. The DC vaccines were produced by co-culturing with whole tumor antigen which was purified through freezing and melting T24-3 cell subset. After T24-3 cells injected into SCID mice for 5 weeks, the mice were treated with DC vaccines. All mice were initially treated at 5th week. The expression of CK20 mRNA in peripheral blood of DC vaccines treated mice was the lowest. There was 2 mice showing CK20 mRNA expression and 3 mice with metastasis tumor in PBS group. MMP-7 mRNA expression in tumor tissues of DC vaccines treated mice was statistically lower than that of PBS group (P < 0.01). DC vaccines have a good effect on hu-PBL-SCID mice bladder cancer model by reducing hematogenous micrometastasis.