Quantitation of antibody isotypes in solid-phase assays. Comparison of myeloma protein and monoisotypic antibody standards.
Two methods have been proposed for the standardization of isotype specific antibody assays. In one, myeloma proteins directly attached to plastic surfaces are used as standards, whereas the other method employs antigen coated surfaces followed by monoisotypic antibodies as standards. These standardization methodologies have been investigated by submitting 4 monoisotypic human antibodies to a solid-phase assay standardized by the myeloma method. Specific antibody concentrations of each were determined so that each could serve as a monoisotypic standard. Three purified monoclonal mouse antibodies were also tested which allowed use of the same preparation as a monoisotypic antibody standard or as a 'myeloma protein' standard. Ten times more myeloma protein than specific antibody is needed for the same level of binding of the anti-isotype antibody. Therefore, assays standardized with myeloma proteins give erroneously high concentrations for sample antibodies. The same concentration of antibodies of different specificities (used with different antigen coats) gave very comparable levels of binding of the labeled antibody. This supports the claim that for quantitation of antibodies an antibody standard can be used that is of different specificity to the sample antibody to be measured.
D000818:Animals; D000906:Antibodies / Q000032:analysis* / Q000145:classification; D000907:Antibodies, Bacterial / Q000032:analysis / Q000145:classification; D000911:Antibodies, Monoclonal; D006510:Hepatitis B Antibodies / Q000032:analysis / Q000145:classification; D006801:Humans; D007136:Immunoglobulins / Q000032:analysis* / Q000145:classification; D007163:Immunosorbent Techniques / Q000592:standards*; D051379:Mice
D000906:Antibodies; D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D006510:Hepatitis B Antibodies; D007136:Immunoglobulins