Myeloma proteins as tumor-specific transplantation antigens

BALB/c mice immunized with myeloma proteins 315 or 460 made antibodies to the individually specific ("idiotypic") determinants of these proteins and suppressed growth of the corresponding transplanted tumor cells (MOPC-315 or MOPC-460). Stable, variant MOPC-315 tumors that produce only the light chain of protein 315 grew in several of the mice immunized with this protein, probably because the anti-idiotypic immune response selects against those myeloma cells that form the intact myeloma protein.