The granulocyte macrophage–colony stimulating factor surface modified MB49 bladder cancer stem cells vaccine against metastatic bladder cancer

• MCSCs were isolated by a combination of the limited dilution method and the optimal serum free culture medium method.
• MCSCs possessed the characteristics resembling CSCs.
• SA–mGM–CSF MCSCs vaccine induces antitumor immune response to metastatic bladder cancer.

The MB49 bladder cancer cell vaccine was effective against bladder cancer in the mice model in previous studies. However, part of the tumors regrew as the vaccine could not eliminate the cancer stem cells (CSCs). MB49 bladder cancer stem cells (MCSCs) were isolated by a combination of the limited dilution method and the serum free culture medium method. MCSCs possessed higher expression of CD133, CD44, OCT4, NANOG, and ABCG2, the ability of differentiation, higher proliferative abilities, lower susceptibility to chemotherapy, greater migration in vitro, and stronger tumorigenic abilities in vivo. Then streptavidin–mouse granulocyte macrophage–colony stimulating factor (SA–mGM–CSF) MCSCs vaccine was prepared. SA–mGM–CSF MCSCs vaccine extended the survival of the mice and inhibited the growth of tumor in protective, therapeutic, memorial and specific immune response experiments. The level of immunoglobulin G and the ratio of dendritic cells and CD4+ and CD8+ T cells were highest in the experimental group when compared to those in other four control groups, as well as for the cytotoxicity assay. We demonstrated that SA–mGM–CSF MCSCs vaccine induces an antitumor immune response to metastatic bladder cancer.