Binding of a soluble p70 killer cell inhibitory receptor to HLA-B*5101: requirement for all three p70 immunoglobulin domains

Eur J Immunol. 1997 Feb;27(2):568-71. doi: 10.1002/eji.1830270231.


Lysis of target cells by natural killer (NK) cells can be prevented by killer cell inhibitory receptors (KIR) specific for major histocompatibility complex class I molecules. Functional studies have identified two distinct p58 KIR, each reactive with a different group of HLA-C allotypes, and distinct p70 KIR specific for some HLA-B or HLA-A allotypes. The NK specificities for each group of HLA-C allotypes have been reproduced by direct binding of recombinant soluble p58 molecules. Here, we show that a soluble p70 KIR binds to HLA-B*5101, but not to HLA-A or HLA-C molecules. Truncated soluble forms of the HLA-B*5101-specific p70 KIR, including one with two immunoglobulin (Ig) domains reactive with a monoclonal antibody that blocks p70 KIR function, did not bind to HLA-B*5101, indicating that all three Ig domains are required for binding.

MeSH terms

  • HLA-B Antigens / metabolism*
  • HLA-B51 Antigen
  • Humans
  • Immunoglobulins / chemistry*
  • Killer Cells, Natural / metabolism*
  • Peptide Fragments / immunology*
  • Protein Binding / immunology
  • Receptors, Immunologic / chemistry
  • Receptors, Immunologic / metabolism*
  • Receptors, Immunologic / physiology


  • HLA-B Antigens
  • HLA-B51 Antigen
  • Immunoglobulins
  • Peptide Fragments
  • Receptors, Immunologic
  • p70 natural killer cell receptor