title: Novel approaches using alkaline or acid/guanidine treatment to eliminate therapeutic antibody interference in the measurement of total target ligand.
abstract: Measurement of the total target ligand can help to provide pharmacokinetic (PK) and pharmacodynamic (PD) informations. However, the presence of monocloncal antibody therapeutics (ThAs) interferes with ELISA determinations of the total target proteins. The interferences can cause over- or under-estimation of the target protein analysis. The nature of interferences was dependent upon the ThA, target protein, antibody reagents and assay conditions of the ELISA. We have developed novel alkaline and acid/guanidine treatment approaches to dissociate the protein binding and preferentially denature the ThA. The neutralized target proteins can be determined by ELISA. These methods provide reproducible measurements of total target protein without ThA interference. Serum samples, standards and QCs containing target protein and ThA were treated with alkaline buffer (pH>13) containing casein or acid/guanidine buffer (pH<1). Total target proteins for two different ThA systems were successfully measured and interferences were completely eliminated by the treatments. These methods were successfully applied to analysis in pre-clinical serum samples.
authors.affiliation: Department of Pharmacokinetics & Drug Metabolism, Amgen Inc., One Amgen Center Dr., Thousand Oaks, CA 91320, United States. hsalimi@amgen.com
authors.forename: Hossein
authors.initials: H
authors.lastname: Salimi-Moosavi
authors.forename: Jean
authors.initials: J
authors.lastname: Lee
authors.forename: Binodh
authors.initials: B
authors.lastname: Desilva
authors.forename: George
authors.initials: G
authors.lastname: Doellgast
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000737:chemistry / Q000378:metabolism* / Q000627:therapeutic use; D000937:Antigen-Antibody Reactions; D001666:Binding Sites, Antibody; D001798:Blood Proteins / Q000032:analysis* / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D019791:Guanidine / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D011487:Protein Conformation; D011489:Protein Denaturation; D015203:Reproducibility of Results
chemical_list: D000911:Antibodies, Monoclonal; D001798:Blood Proteins; D008024:Ligands; D019791:Guanidine