Association of killer cell immunoglobulin–like receptor genotypes with vascular arterial events and anticardiolipin antibodies in patients with lupus

Abstract

To determine whether killer cell immunologlobulin–like receptor (KIR) genotypes are associated with vasculitis, vascular arterial events or anticardiolipin (aCL) antibodies in patients with lupus. A total of 304 patients followed prospectively at the University of Toronto Lupus Clinic were assessed for the occurrence of vasculitis and vascular arterial events. Molecular HLA-C and KIR (presence or absence of KIR2DL1, 2DL2, 2DL3, 2DS1 and 2DS2) genotyping were performed. Chi-square and logistic regression were used to analyse association between KIR genes and vascular arterial events and aCL antibodies. In patients with vascular arterial events, there was a significant increase in KIR2DS2 (60% vs 45%, P = 0.02) and in KIR2DL2 (62% vs 47%, P = 0.01) compared with patients without events. There was no increase in activating KIR genotypes in patients with vasculitis. In patients with aCL antibodies, significant increases were seen in KIR2DS2 (54% vs 41%, P = 0.03) and KIR2DL2 (58% vs 41%, P = 0.003), but KIR2DL3 was decreased (87% vs 95%, P = 0.03). Logistic regression confirmed independent association of KIR2DS2 with vascular arterial events. We found an increase in KIR2DS2 in lupus patients with vascular arterial events, but not in patients with vasculitis.