Molecular insights into γδ T cell costimulation by an anti-JAML antibody

Structure. 2011 Jan 12;19(1):80-9. doi: 10.1016/j.str.2010.10.007.

Abstract

γδ T cells bridge innate and adaptive immunity and function in immunosurveillance, immunoregulation, tumor cell recognition, and as first line of defense against microbial infection. Costimulation of epithelial γδ T cell activation by the JAML receptor can be induced by interaction with its endogenous ligand CAR or by binding of the stimulatory antibody HL4E10. We, therefore, determined the crystal structure of the JAML-HL4E10 Fab complex at 2.95 Å resolution. HL4E10 binds the membrane-proximal domain of JAML through hydrophobic interactions that account for nanomolar affinity and long half-life, contrasting with the fast kinetics and micromolar affinity of the hydrophilic CAR interaction with the membrane-distal JAML domain. Thus, despite different binding sites and mechanisms, JAML interaction with these two disparate ligands leads to the same functional outcome, namely JAML triggering and induction of cell signaling. Several characteristics of the HL4E10 antibody might then be harnessed in therapeutic applications, such as promoting healing of acute or chronic wounds.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Heterophile / chemistry
  • Antibodies, Heterophile / pharmacology*
  • Antibodies, Monoclonal / chemistry
  • Antibodies, Monoclonal / pharmacology*
  • Binding Sites, Antibody
  • Cell Adhesion Molecules / chemistry
  • Cell Adhesion Molecules / immunology
  • Cell Adhesion Molecules / metabolism*
  • Cell Line
  • Cell Proliferation
  • Coxsackie and Adenovirus Receptor-Like Membrane Protein
  • Cricetinae
  • Crystallography, X-Ray
  • Hydrophobic and Hydrophilic Interactions
  • Immunoglobulin Fab Fragments / chemistry
  • Langerhans Cells / cytology
  • Langerhans Cells / metabolism*
  • Mice
  • Phosphatidylinositol 3-Kinases / physiology
  • Protein Binding
  • Protein Interaction Domains and Motifs
  • Protein Structure, Quaternary
  • Receptors, Antigen, T-Cell, gamma-delta / metabolism*
  • Receptors, Virus / chemistry
  • Receptors, Virus / metabolism
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism*
  • Surface Properties
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*

Substances

  • Antibodies, Heterophile
  • Antibodies, Monoclonal
  • CLMP protein, mouse
  • Cell Adhesion Molecules
  • Coxsackie and Adenovirus Receptor-Like Membrane Protein
  • Immunoglobulin Fab Fragments
  • JAML protein, mouse
  • Receptors, Antigen, T-Cell, gamma-delta
  • Receptors, Virus
  • Recombinant Fusion Proteins

Associated data

  • PDB/3MJ9