Abstract:

Abstract:Objective  To study the anti-tumor effect of recombinant human MUC1-MBP and mouse Muc1-MBP protein vaccines,and  provide the basis for clinical application of tumor vaccine.Methods The mice were divided three groups and respectively immunized with PBS  (negative control),human MUC1-MBP and mouse Muc1-MBP fusion protein.The cross reaction between anti-human MUC1 and anti-mouse Muc1 antibody was detected by ELISA.CTL-specific cytotoxicities of mice induced by MUC1 and Muc1 were detected by LDH.The anti-tumor effects of human MUC1 and mouse Muc1 were observed by establishing mice models of the lung cancer metastasis and the subcutaneous human breast cancer.
Results The cross reaction between the antibody of human MUC1 and the antigen of mouse Muc1 was stronger than that between the antibody of mouse Muc1 and antigen of human MUC1.The cytotoxicities of CTL from immunized mice by human MUC1-MBP and mouse Muc1-MBP to the MCF-7 cells were (48.7±7.1)% and (54.6±7.8)% or to LLC1 cells were (61.9 ±10.2)% and (43.5±8.4)%,respectively.The inhibitory rates of lung tumor nodules  of Lewis lung cancer in human MUC1-MBP and mouse Muc1-MBP groups were 94.4% and 68.5%,respectively.The average tumor volumes in human MUC1-MBP,mouse Muc1-MBP and PBS groups were  (23.5±15.7),(56.5±46.7) and (142.8±70.2) mm3,respectively,in the animal models of human breast cancer. The masses of tumor were obviously suppressed in MUC1-MBP group (P<0.01) and Muc1-MBP group (P<0.05) compared with   control group.Conclusion Human MUC1 and mouse Muc1 have common epitope of B and T cell and the human MUC1 could induce the stronger cross reaction.Human MUC1-MBP has significant anti-tumor effects than that of  mouse Muc1-MBP,and it  might be used to develop the protein vaccine against human carcinoma.

Key words: human MUC1-MBP;mouse Muc1-MBP;recombinant fusion proteins;cancer vaccine;cross reaction