Analysis of Therapeutic Monoclonal Antibodies in Serum

Monoclonal antibodies (mAbs) are one of the most successful classes of therapeutic drugs.  Due to their high specificity for a given antigen, they effectively treat a variety of cancers, autoimmune diseases, inflammatory diseases, and infections.  One challenge in these treatments is that antibody levels in blood may vary widely among patients.  Graduate students Joshua Berwanger and Hui Yin Tan aim to create simple and rapid methods for determining monoclonal antibody concentration in serum or plasma to better inform dosing schedules.

The assays employ mimotope-modified membranes to selectively capture a specific mAb (the figure at the right gives the scheme of selective Bevacizumab capture).  Mimotopes are peptides that mimic the antigen of an antibody.  Our recent research showed the development of mimotope-modified membranes for capture of three different therapeutic mAbs Anal. Chem. 93, 7562–7570 (2021). After selective binding of a mAb, capture of a fluorescently labelled secondary antibody leads to a fluorescence signal that is proportional to the antibody concentration (see the figure below).  With appropriate membrane-based devices such analyses can occur in 5 minutes. Our most recent reseach demonstrated the capture of a COVID-19 monoclonal antibody using membranes containing an immobilized COVID-19 protein. 

We are grateful to the National Science Foundation (CHE1903967) and the NSF IUCRC Center for Bioanalytical Metrology (1916601 and RAPID-IIP-2031090) for funding the work.