Multiple lineages of tumors express a common tumor antigen, P1A, but they are not cross-protected.
Whether tumors of different lineages share common Ags is a critical issue for understanding anti-tumor immune responses and for designing Ag-specific tumor immunotherapy. Because of lack of cross-protection among individually derived tumors, it has been proposed that tumor Ags are specific for individual tumors. Here we show that lack of cross-protection is not due to lack of a shared tumor Ag. Thus, a plasmocytoma J558 transfected with the costimulatory molecule B7 activates a cross-reactive CTL response in vivo. The major Ag recognized by the cross-reactive CTL is P1A, which is expressed in mastocytoma P815, plasmocytoma J558, and fibrosarcoma Meth A. Surprisingly, no significant cross-protection can be detected among P1A-expressing tumors after immunization with either P1A-expressing or B7-transfected P815 cells. Our results demonstrate that multiple lineages of tumors are not cross-protected even though they share a tumor Ag that can be recognized by CTL. These results have important implications for tumor immunotherapy.
Ramarathinam
L
L
Michael Heidelberger Division of Immunology, Department of Pathology, New York University Medical Center, New York 10016, USA.
Sarma
S
S
Maric
M
M
Zhao
M
M
Yang
G
G
Chen
L
L
Liu
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D018122:B7-1 Antigen / Q000276:immunology; D001483:Base Sequence; D003429:Cross Reactions / Q000276:immunology*; D017931:DNA Primers; D000939:Epitopes / Q000276:immunology; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D009368:Neoplasm Transplantation; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014162:Transfection; D014407:Tumor Cells, Cultured
D000951:Antigens, Neoplasm; D018122:B7-1 Antigen; D017931:DNA Primers; D000939:Epitopes; C076546:tumor rejection antigen P815A, mouse