Characterization of a melanoma antigen with a mouse-specific epitope recognized by a monoclonal antibody with antimetastatic ability.

We have characterized properties of a melanoma antigen with a mouse-specific melanoma epitope expressed on B16 melanoma by using syngeneic monoclonal antibodies with antimetastatic ability. The molecule recognized by the antibody is a membrane glycoprotein with a molecular weight of 80,000. Studies on tunicamycin treatment indicated that the core size of the molecule appeared to have a molecular weight of 69,000 and also suggested that the carbohydrate moiety was greatly responsible for the conformation of the mouse melanoma epitope. The antigen was released or shed into the culture medium from the cell surface, and the turnover rate of the antigen was within 1.5 h.