Functional CD32 molecules on human NK cells

Human NK cells are large granular lymphocytes that kill neoplastic or viral ly infected targets using perforin-dependent mechanisms. CD16 or Fc gamma R III is one of the cell surface molecules that can trigger the killing machi nery following binding of the Fc portion of IgG to the receptor: a mechanis m known as antibody dependent cell-mediated cytotoxicity (ADCC). We have re cently shown that some individuals express an additional Fc gamma R on thei r NK cells, CD32 or Fc gamma RII. This receptor has now been characterized at the molecular, biochemical and functional level. The present review outl ines our findings to date on the features of this novel receptor. These fin dings suggest that the presence of a functional Fc gamma RII on the surface of NK cells could have important clinical consequences in both turner immu notherapy and autoimmune disease.