Tumor Immunity Induced by Preimmunization With BALB/c Mouse Myeloma Protein

Summary

Prior sc immunization of BALB/c mice with 1 mg isolated M component of MOPC-11 mouse myeloma resulted in significant relative immunity to subsequent sc or ip challenge with 10⁴ living cells from the same plasmacytoma. However, challenges of 10⁵ and 10⁶ tumor cells overcame immune status engendered by preimmunization with M component. Despite evidence for the specificity of the immunity induced by one isolated M component as opposed to another, no clear cytotoxic antibody, cell-mediated tumor-cell lysis, or predominance of either humoral or cell-mediated immune mechanisms were demonstrated. These findings were compatible with a relatively slight tumor-specific antigenicity of M components expressed on tumor surfaces, compared with the tumor specificity of other tumor-related, cell-surface antigens.