The use of specific adoptive therapy for treating established tumors is based on the suppositions that tumor cells express surface antigens which can serve as targets for immunologic attack, that lymphocytes recognizing these antigens can be obtained in sufficient number by methods of purification and/or generation, and that adoptive transfer of these antigen-specific lymphocytes into a tumor-beating host can mediate a significant antitumor effect in vivo without undue toxicity to the host. The initial enthusiasm which ar'ticipated the use of adoptive immunotherapy as a therapeutic modality was largely based on studies demonstrating that many animal tumors express immunogenic tumorassociated antigens (TAA), and that lymphocytes immune to these TAA can mediate specific in vitro lysis of the tumor cells. More-