Syngeneic antiidiotypic monoclonal antibodies to the murine anti-HLA-DR,DP monoclonal antibody CR11-462.
Two out of 625 hybridomas constructed with splenocytes from a Balb/c mouse immunized with the murine anti-HLA-DR, DP monoclonal antibody CR11-462 secrete antiidiotypic antibodies. Binding assays with a panel of 12 anti-HLA class I, 14 anti-HLA class II, and 9 anti-human melanoma-associated antigen MoAbs showed that the idiotopes recognized by MoAb F3-C25 and F3-B6 are not expressed by any of the tested antibodies, even those which inhibit the binding of MoAb CR11-462 to cultured B lymphoid cells. Crossblocking experiments showed that the two idiotopes are distinct and spatially distant. Both idiotopes require the association of heavy and light chain of MoAb CR11-462 for their expression. The idiotope recognized by MoAb F3-B6 is an alpha idiotope, since it is located outside the antigen combining site of MoAb CR11-462. The idiotope recognized by MoAb F3-C25 is a gamma idiotope, since it is antigen inhibitable but does not possess an internal image of the antigen. Interestingly the MoAb F3-C25 displays a differential inhibitory effect on the binding of MoAb CR11-462 to lymphoid cells that express different HLA phenotypes or share the HLA-DRw6 allospecificity. These results suggest that antiidiotypic antibodies may sharpen our ability to dissect the heterogeneity of HLA class II antigens.
Perosa
F
F
Department of Microbiology and Immunology, New York Medical College, Valhalla 10595.
Ferrone
S
S
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000096:biosynthesis; D000911:Antibodies, Monoclonal; D001666:Binding Sites, Antibody; D006682:HLA-DP Antigens / Q000276:immunology*; D006684:HLA-DR Antigens / Q000276:immunology*; D007130:Immunoglobulin Idiotypes / Q000096:biosynthesis; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D006682:HLA-DP Antigens; D006684:HLA-DR Antigens; D007130:Immunoglobulin Idiotypes