KLRC2

Natural killer (NK) cells are lymphocytes that can mediate lysis of certain tumor cells and virus-infected cells without previous activation. They can also regulate specific humoral and cell-mediated immunity. NK cells preferentially express several calcium-dependent (C-type) lectins, which have been implicated in the regulation of NK cell function. The group, designated KLRC (NKG2) are expressed primarily in natural killer (NK) cells and encodes a family of transmembrane proteins characterized by a type II membrane orientation (extracellular C terminus) and the presence of a C-type lectin domain. The KLRC (NKG2) gene family is located within the NK complex, a region that contains several C-type lectin genes preferentially expressed on NK cells. KLRC2 alternative splice variants have been described but their full-length nature has not been determined.

KLRC2 has been shown to interact and form dimers with CD94. The CD94/NKG2C heterodimer can bind to HLA-E and this binding leads to NK cells activation.

During infection with human cytomegalovirus, peptides derived from the virus are presented on HLA-E and natural killer cells that express the CD94/NKG2C receptor can specifically recognise the virus peptides. This recognition leads to activation, expansion, and differentiation of adaptive NK cells.