Ligands for murine NKG2D display heterogeneous binding behavior

Eur J Immunol. 2002 Mar;32(3):597-605. doi: 10.1002/1521-4141(200203)32:3<597::aid-immu597>;2-5.


NKG2D transmits stimulatory signals to natural killer cells and other hematopoietic cells, leading to enhanced proliferation, cytokine secretion and target killing. Murine and human NKG2D each recognize five known class I-related molecules with distinct primary structures. Here, we used surface plasmon resonance to examine the binding of murine NKG2D to its cognate ligands: RAE-1B6 (a newly described C57BL/6J variant of RAE-1), RAE-1 delta (common to BALB and C57BL6/J), and H60 (expressed in BALB, but not C57BL/6J). While RAE-1B6 and H60 display relatively high affinities for NKG2D with K(D) in the 20-30 nM range and k(off )in the 0.03s(-1) to 0.06s(-1) range (t(1/2) approximately 10-20s); the RAE-1 delta variant binds with a lower affinity: K(D) of approximately 750 nM. Furthermore, RAE-1 delta displays biphasic kinetics with dominant k(off) of approximately 0.2s(-1) (t(1/2) approximately 3s), partially explaining the lower affinity. Thus, H60 and RAE-1B6 bind NKG2D with almost identical kinetics while sharing only 20% amino acid sequence identity; whereas other RAE-1 molecules demonstrate faster dissociation and lower affinities than RAE-1B6 despite sharing 90% sequence identity. C57BL/6J mice, although not expressing the H60 gene product, retain a high-affinity ligand for NKG2D in the form of RAE-1B6.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Cell Line
  • Escherichia coli / genetics
  • Kinetics
  • Ligands
  • Membrane Proteins / metabolism*
  • Mice
  • Mice, Inbred C57BL
  • Minor Histocompatibility Antigens / metabolism*
  • Molecular Sequence Data
  • NK Cell Lectin-Like Receptor Subfamily K
  • Nucleopolyhedroviruses / genetics
  • Protein Binding
  • Receptors, Immunologic / metabolism*
  • Receptors, Natural Killer Cell
  • Recombinant Fusion Proteins / metabolism
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Spodoptera / cytology


  • KLRK1 protein, human
  • Klrk1 protein, mouse
  • Ligands
  • Membrane Proteins
  • Minor Histocompatibility Antigens
  • NK Cell Lectin-Like Receptor Subfamily K
  • Rae-1B6 protein, mouse
  • Raet1a protein, mouse
  • Receptors, Immunologic
  • Receptors, Natural Killer Cell
  • Recombinant Fusion Proteins
  • minor H antigen H60