Functional Antagonism of Human CD40 Achieved by Targeting a Unique Species-Specific Epitope. Issue 14 (17th July 2016)

• Record Type: Journal Article
• Authors: Yamniuk, Aaron P.; Suri, Anish; Krystek, Stanley R.; Tamura, James; Ramamurthy, Vidhyashankar; Kuhn, Robert; Carroll, Karen; Fleener, Catherine; Ryseck, Rolf; Cheng, Lin; An, Yongmi; Drew, Philip; Grant, Steven; Suchard, Suzanne J.; Nadler, Steven G.; Bryson, James W.; Sheriff, Steven
• Is Part Of: Journal of molecular biology. Volume 428:Issue 14(2016:Jul. 15)
• Page Start: 2860
• Page End: 2879
• Publication Date: 2016-07-17
• Subjects: APCs antigen-presenting cells -- mAbs monoclonal antibodies -- dAbs domain antibodies -- NHPs nonhuman primates -- hCD40 human CD40 -- DC dendritic cell -- CDR complementarity-determining region -- SPR surface plasmon resonance -- NHS N-hydroxysuccinimide -- SEC size exclusion chromatography -- PBST PBS containing Tween 20 -- RU resonance units -- IZ isoleucine zipper -- IZ-hCD40L trimeric IZ human-CD40L -- iDCs immature DCs -- RB round bottom; CD40 -- X-ray structure -- autoimmune disease -- domain antibody -- therapeutic; Molecular biology -- Periodicals; Biology -- Periodicals; Biochemistry -- Periodicals; Bacteriology -- Periodicals; Molecular Biology -- Periodicals; Biochemistry -- Periodicals; Biologie moléculaire -- Périodiques; Biologie -- Périodiques; Biochimie -- Périodiques; Moleculaire biologie; Biochemistry; Biology; Molecular biology; Periodicals; 572.805
• DOI: 10.1016/j.jmb.2016.05.014
• Languages: English
• ISSNs: 0022-2836

Abstract

Abstract: Current clinical anti-CD40 biologic agents include both antagonist molecules for the treatment of autoimmune diseases and agonist molecules for immuno-oncology, yet the relationship between CD40 epitope and these opposing biological outcomes is not well defined. This report describes the identification of potent antagonist domain antibodies (dAbs) that bind to a novel human CD40-specific epitope that is divergent in the CD40 of nonhuman primates. A similarly selected anti-cynomolgus CD40 dAb recognizing the homologous epitope is also a potent antagonist. Mutagenesis, biochemical, and X-ray crystallography studies demonstrate that the epitope is distinct from that of CD40 agonists. Both the human-specific and cynomolgus-specific molecules remain pure antagonists even when formatted as bivalent Fc-fusion proteins, making this an attractive therapeutic format for targeting hCD40 in autoimmune indications. Graphical Abstract: Highlights: Can agonist and antagonist activities be separated for CD40 therapeutic agents? dAbs identified with unique human-specific antagonist epitope. X-ray crystal structures show molecular details of dAb and antibody epitopes. Cynomolgus-specific surrogate dAb molecules generated, also potent antagonist dAbs targeted to unique epitope are functional antagonists as bivalent Fc-fusion.