Development of an immunoassay for aglycosylated murine IgG1 in mouse serum via generation of a specific tool antibody

Aim: To develop a method for the quantitation of effector functionless mouse surrogate IgG1 drug molecules in mouse matrices. Materials & methods: A panel of antibodies that bound specifically to N297G mutation-containing mouse IgG molecules was generated in rats. The panel was screened to identify an antibody that could be used as both the capture and detection reagent in an electrochemiluminescent immunoassay. Results & conclusion: The quantitative assay developed with the N297G-specific antibody passed acceptance criteria across multiple IgG1 fragment crystallizable (Fc)-containing protein formats and provides accurate quantitation of the total levels of mouse surrogate protein Fc present in in vivo mouse serum samples. These results are useful in understanding drug integrity and the development of precise pharmacokinetic/pharmacodynamic relationships.