Autologous killing of macrophages and monocytes by NK cells or NKG2D-expressing CD4+ T cells was shown after induction of NKG2D ligand expression on monocytes by lipopolysaccharide (LPS) stimulation, in vitro culture with IL-10, or on monocytes from patients with systemic lupus erythematosus (44–46). The gene discussed is KLRK1; the disease is systemic lupus erythematosus.