Format

Send to

Choose Destination
Front Immunol. 2017 Apr 24;8:455. doi: 10.3389/fimmu.2017.00455. eCollection 2017.

Real-time Characterization of Antibody Binding to Receptors on Living Immune Cells.

Author information

1
Ridgeview Instruments AB, Vänge, Sweden.
2
Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden.
3
Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK.
4
Pfizer Inc., Cambridge, MA, USA.
5
BioRevera LLC, Arlington, MA, USA.

Abstract

Understanding molecular interactions on immune cells is crucial for drug development to treat cancer and autoimmune diseases. When characterizing molecular interactions, the use of a relevant living model system is important, as processes such as receptor oligomerization and clustering can influence binding patterns. We developed a protocol to enable time-resolved analysis of ligand binding to receptors on living suspension cells. Different suspension cell lines and weakly adhering cells were tethered to Petri dishes with the help of a biomolecular anchor molecule, and antibody binding was analyzed using LigandTracer. The protocol and assay described in this report were used to characterize interactions involving eight cell lines. Experiments were successfully conducted in three different laboratories, demonstrating the robustness of the protocol. For various antibodies, affinities and kinetic rate constants were obtained for binding to CD20 on both Daudi and Ramos B-cells, the T-cell co-receptor CD3 on Jurkat cells, and the Fcγ receptor CD32 on transfected HEK293 cells, respectively. Analyzing the binding of Rituximab to B-cells resulted in an affinity of 0.7-0.9 nM, which is similar to values reported previously for living B-cells. However, we observed a heterogeneous behavior for Rituximab interacting with B-cells, which to our knowledge has not been described previously. The understanding of complex interactions will be facilitated with the possibility to characterize binding processes in real-time on living immune cells. This provides the chance to broaden the understanding of how binding kinetics relate to biological function.

KEYWORDS:

B-cells; CD20; Fcγ receptor; T-cells; affinity; kinetics; therapeutic antibody

Supplemental Content

Full text links

Icon for Frontiers Media SA Icon for PubMed Central
Loading ...
Support Center