Production of MUC1 vaccine cells by transfecting MUC1-cDNA plasmid to EBV-lymphoblastoid cells

Polymorphic epithelial cell mucin antigen MUC1, expressed on the surface of many kinds of tumor cells, is a good target for tumor immunotherapy. The Epstein-Barr virus (EBV)-induced lymphoblastoid cell line established from peripheral blood of a healthy donor was transfected with MUC1 cDNA plasmid in order to construct MUC1 vaccine cells. K-EB-MUC1 cells, the thus constructed vaccine cells, strongly expressed both MUC1 and B7 antigens. Cocultivation of autologous peripheral blood lymphocytes with ⁶⁰Co-irradiated K-EB-MUC1 cells in the serum free medium supplemented with IL-1 (50 U/mL or 200 U/ml) induced two types (CD16 dominant and CD8-dominant) of killer cells, both demonstrating remarkable cytotoxicity to tumor cells. Inasmuch as EBV- lymphoblastoid cells transfected with MUC1-plasmid express both tumor and B7 antigens simultaneously, they should be promising vaccine cells for immunotherapy.