Induction of protective antitumor immune response against a murine plasmacytoma not curable by alkylating-drug treatment.
Immunization with viable tumor cells followed by subsequent administration of glutaraldehyde-treated tumor cells induced a protective antitumor immune response in the host toward the alkylating-drug resistant RPC-5 plasmacytoma. This was proven by resistance to challenge with RPC-5 tumor cells, neutralization in Winn tests, by effectiveness of combined chemotherapy with melphalan plus immunotherapy with spleen cells from RPC-5 immunized mice and in vitro by cytotoxicity tests. The specificity of the immune response was ascertained in vivo by comparison with the response toward MOPC-315 plasmacytoma. However, in vitro cytotoxicity tests revealed the occurrence of shared antigens between the RPC-5 and MOPC-315 tumor cells. It is concluded that the ineffectiveness of alkylating-drug treatment toward the RPC-5 tumor is not due to the inability of this tumor to induce a specific antitumor immune response, and that cross-antigenic relationship as revealed by in vitro cytotoxicity tests does not necessarily reflect cross-protection between various plasmacytomas.
Ophir
R
R
Department of Human Microbiology, Sackler School of Medicine, Tel-Aviv University, Israel.
Jackman
A
A
Relyveld
E H
EH
Ben-Efraim
S
S
D000818:Animals; D003131:Combined Modality Therapy; D004351:Drug Resistance; D007114:Immunization; D008297:Male; D008558:Melphalan / Q000627:therapeutic use*; D051379:Mice; D008807:Mice, Inbred BALB C; D010954:Plasmacytoma / Q000188:drug therapy / Q000276:immunology*
D008558:Melphalan