CD70 recruitment to the immunological synapse is dependent on CD20 in B cells
Abstract
CD20 is a four-transmembrane protein expressed at the surface of B cells from late pro-B cells to memory B cells, with the exception of plasma cells. Its expression pattern makes it an attractive therapeutic target for different B cell malignancies and autoimmune diseases. Despite the clinical success of CD20-targeting antibodies, the biology of the CD20 protein is still not well understood. We investigated CD20 binding partners in the membrane of human B cells using immunoprecipitation followed by mass spectrometry analysis. We identified a molecular interaction between CD70 and CD20, and confirmed this using proximity ligation assays. CD20–CD70 spatiotemporal colocalization was validated at the plasma membrane of B cells using high-resolution microscopy. Cell surface expression of CD70 was found to be enhanced upon CD20 overexpression, suggesting a role for CD20 in stabilizing CD70 at the B cell membrane. Moreover, we observed impaired B-T cell synapse formation and defective recruitment of CD70 to the immunological synapse in the absence of CD20. Impaired synapse formation was confirmed by deleting CD20 in primary B cells, and analysis of B cells from a CD20-deficient patient. Finally, CD20-deletion resulted in diminished T cell activation and cytokine secretion. Together, this study demonstrates that CD20 interacts with CD70 at the B cell membrane, and that CD20 is required for immune synapse formation between B and T cells and consequent T cell activation.
Article Details
Journal Info
Proceedings of the National Academy of Sciences
National Academy of Sciences
Authors (24)
Abbey B. Arp
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Andrea Abel Gutierrez
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Martin ter Beest
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Guus A. Franken
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Harry Warner
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Andrea Rodgers Furones
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Angelique N. Kenyon
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Franziska Jäger
Department of Chemistry, Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University
Alfredo Cabrera-Orefice
Radboud Institute for Medical Innovation, Radboud University Medical Center
Kathrin Kläsener
Department of Molecular Immunology, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies, Centre for Biological Signalling Studies, Biology III, Faculty of Biology, University of Freiburg
Sjoerd van Deventer
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Lenny Droesen
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
Vera Marie E. Dunlock
Department of Medical BioSciences, Radboud Institute for Medical Innovation, Radboud University Medical Center
René Classens
Department of Medical BioSciences, Radboudumc
Julian Staniek
Department of Rheumatology and Clinical Immunology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg
Jannie Borst
Department of Immunology, Leiden University Medical Center
Michael Reth
Department of Molecular Immunology, Centre for Biological Signalling Studies and Centre for Integrative Biological Signalling Studies, Centre for Biological Signalling Studies, Biology III, Faculty of Biology, University of Freiburg
Ulrich Brandt
Radboud Institute for Medical Innovation, Radboud University Medical Center
Piet Gros
Department of Chemistry, Structural Biochemistry, Bijvoet Centre for Biomolecular Research, Faculty of Science, Utrecht University
Taco W. Kuijpers
Department of Pediatric Immunology, Rheumatology and Infectious Diseases, Emma Children’s Hospital, Amsterdam University Medical Center
Mirjam H. M. Heemskerk
Department of Hematology, Leiden University Medical Center
Marta Rizzi
Department of Rheumatology and Clinical Immunology, University Medical Center Freiburg, Faculty of Medicine, University of Freiburg
Laia Querol Cano
Department of Medical BioSciences, Radboudumc
Annemiek B. van Spriel
Department of Medical BioSciences, Radboudumc