Characterization of four monoclonal antibodies to factor VIII coagulant protein and their use in immunopurification of factor VIII.
Four monoclonal anti-VIII:C antibodies were obtained from the fusion of the splenocytes of one Balb/C mouse with a specific activity ranging from 2.3 to 45,000 U/mg when purified from ascitic fluid. Only one antibody was able to inhibit completely Factor VIII:C in normal plasma. The four antibodies could bind Factor VIII:CAg in plasma and commercial concentrate both in liquid and solid phase, and were suitable for immunopurification of Factor VIII:C. Three antibodies competed with polyclonal anti-VIII:CAg Fab' in a liquid phase IRMA, and all of them were able to displace their own binding to Factor VIII:CAg. Competition studies between monoclonal antibodies for the binding to Factor VIII:CAg were performed and showed the recognition of different epitopes and various functional impact. These studies indicate that at least one antibody, with the lowest anti-VIII:C titer clearly recognizes a different epitope of VIII:C than those recognized by the others. Affinity constants ranged from 10(9) to 10(10) l/mole.
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000302:isolation & purification*; D000915:Antibody Affinity; D000937:Antigen-Antibody Reactions; D001667:Binding, Competitive; D002846:Chromatography, Affinity; D000939:Epitopes / Q000032:analysis; D005169:Factor VIII / Q000032:analysis* / Q000276:immunology / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D006825:Hybridomas / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D008807:Mice, Inbred BALB C
D000911:Antibodies, Monoclonal; D000939:Epitopes; D005169:Factor VIII