Murine monoclonal anti-idiotypic antibody as a surrogate antigen for human Her-2/neu.
The anti-idiotypic (Id) monoclonal antibody (MAb) 520C9-6b (IgG1k), raised in syngenic mice against the murine anti-Her2/neu MAb 520C9 (Ab1), functionally mimics a human Her2/neu epitope and serves as a surrogate for the protein antigen. Immunization of allogeneic C57BL/6 mice and rabbits with 520C9-6b (Ab2) induced anti-Her2/neu-specific antibodies that react with antigen-positive SKBr3 cells by ELISA and FACS analysis. The immune sera inhibited binding between Ab1 and Ab2 and vice versa (binding of Ab2 to Ab1), indicating that it was a true anti-anti-Id (Ab3) antibody. The Ab3 sera or purified Ab3 specifically lysed Her2/neu-positive SKBr3 cells, but no significant lysis was observed in antigen-negative LS174T cells in an antibody-dependent cellular cytotoxicity assay. An Id-specific cellular immune response was also demonstrated in an in vitro lymphocyte proliferation assay. Furthermore, a panel of tumor tissues and tumor cells was screened for the presence of the Her2/neu epitope by its reactivity with Ab1 and Ab3 using immunohistochemistry and FACS analysis. Identical results were obtained using either Ab1 or Ab3 (Ab1'). The data indicated that anti-Id 520C9-6b can induce Her2/neu-specific antibody in experimental animals and may serve as a potential network antigen for the treatment of patients bearing Her2/neu-positive tumors.
Baral
R
R
Division of Hematology/Oncology, Department of Internal Medicine and The Barrett Cancer Center for Prevention, Treatment and Research, University of Cincinnati, OH 45267-0509, USA.
Sherrat
A
A
Das
R
R
Foon
K A
KA
Bhattacharya-Chatterjee
M
M
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology* / Q000302:isolation & purification; D000911:Antibodies, Monoclonal / Q000276:immunology* / Q000302:isolation & purification; D000920:Antibody-Dependent Cell Cytotoxicity; D000941:Antigens / Q000276:immunology*; D000951:Antigens, Neoplasm / Q000276:immunology; D001943:Breast Neoplasms / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D006825:Hybridomas / Q000276:immunology; D007106:Immune Sera / Q000494:pharmacology; D007111:Immunity, Cellular; D007114:Immunization; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011817:Rabbits; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014407:Tumor Cells, Cultured
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000941:Antigens; D000951:Antigens, Neoplasm; D007106:Immune Sera; D018719:Erb-b2 Receptor Tyrosine Kinases