Development of an anti-idiotypic antibody reactive with an antibody defining the epitope RPAP in the MUC-1 epithelial mucin core.
C595 is a murine IgG3 monoclonal antibody (MAb) raised against human urinary mucin. C595 antibody binds to the protein core of the MUC-1 mucin (the polymorphic epithelial mucin, PEM) which is elevated in tissue and secretions from human breast carcinomas. The antibody defines the tetrameric epitope, RPAP. In the present study, a syngeneic anti-idiotypic MAb, 911, was raised in BALB/c mice against the C595 of C595 to its mucin core antigen. In turn, pre-blocking of C595 with a 20 amino-acid mucin core peptide specifically inhibited binding of 911 antibody to C595. Cross-reactivity of antibody 911 was only observed against the IgM MAb, 789/91, which has the same minimum antibody-binding epitope as C595, namely, RPAP. Syngeneic and xenogeneic anti-sera against 911 antibody displayed increased binding to heptameric peptide sequences containing the motif, RPA(P). The anti-idiotypic antibody 911 therefore appears to recognize a site within or close to the binding site of the C595 antibody and thus carries an internal image of the parental mucin epitope. Consequently, the 911 idiotypic network offers a promising model system to investigate the mechanism of anti-idiotype-induced tumour immunity.
Bashford
J L
JL
Cancer Research Laboratories, Nottingham University, UK.
Robins
R A
RA
Price
M R
MR
D000595:Amino Acid Sequence; D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000939:Epitopes / Q000737:chemistry / Q000276:immunology*; D007074:Immunoglobulin G / Q000276:immunology*; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D018396:Mucin-1; D009077:Mucins / Q000737:chemistry / Q000276:immunology*; D009363:Neoplasm Proteins / Q000737:chemistry / Q000276:immunology*; D011817:Rabbits
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D000939:Epitopes; D007074:Immunoglobulin G; D008562:Membrane Glycoproteins; D018396:Mucin-1; D009077:Mucins; D009363:Neoplasm Proteins