Human natural killer cell inhibitory receptors bind to HLA class I molecules.

To obtain direct evidence that human natural killer cell (NK) inhibitory receptors physically interact with polymorphic determinants of major histocompatibility complex class I molecules, a receptor termed NK-associated transcript-2 has been produced as a soluble fusion protein with the human IgG1 Fc portion. This soluble receptor binds specifically to HLA-C alleles with serine 77 and asparagine 80 in cell adhesion assays.