Transformation of LMTK- cells with purified class I genes. V. Antibody-induced structural modification of HLA class I molecules results in potentiation of the fixation of a second monoclonal antibody.
A potentiation phenomenon was observed with HLA-A3 and CW3 transformed murine L cells between anti-HLA class I B10.6 (potentiated) and B10.8 (potentiating) monoclonal antibodies (m.Ab.). Further studies of this phenomenon with these transformed L cells indicated that: 1) no significant specific binding of B10.6 m.Ab. to HLA-A3 and CW3 transformed L cells could be demonstrated by conventional radioimmunoassay or cytofluorometric study in the absence of B10.8 m.Ab.; 2) potentiation of the fixation of B10.6 m.Ab. was induced by other anti-HLA class I m.Ab., which all reacted with the same cluster of antigenic determinants; 3) potentiation reflects an increased specific fixation of B10.6 m.Ab. to HLA class I molecules implicating its combining site; 4) potentiation was mediated by B10.8 Fab fragments. These results indicate that potentiation of the fixation of B10.6 m.Ab. to the HLA-A3 and CW3 molecules expressed by the transformed L cells reflects conformational changes of these molecules after interaction with B10.8 m.Ab.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000032:analysis / Q000502:physiology; D000937:Antigen-Antibody Reactions; D001666:Binding Sites, Antibody; D001667:Binding, Competitive; D002460:Cell Line; D004357:Drug Synergism; D000939:Epitopes / Q000276:immunology; D006680:HLA Antigens / Q000235:genetics / Q000276:immunology*; D015791:HLA-A3 Antigen; D015236:HLA-C Antigens; D006801:Humans; D007140:Immunoglobulin Fab Fragments / Q000276:immunology; D007739:L Cells / Q000276:immunology*; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D014170:Transformation, Genetic
D000911:Antibodies, Monoclonal; D000939:Epitopes; D006680:HLA Antigens; D015791:HLA-A3 Antigen; D015236:HLA-C Antigens; C038653:HLA-C*03 antigen; D007140:Immunoglobulin Fab Fragments