Protective effect of the KIR2DS1 gene in atopic dermatitis.

Atopic dermatitis (AD) is a common skin disease of complex etiology including affected humoral and cellular immune responses. The role of NK cells in development of this disease has been recently postulated, but is still poorly documented. The current study was undertaken to determine the impact of genes for the most polymorphic NK cell receptors, known as killer cell immunoglobulin-like receptors (KIRs), on the development of AD. We compared 240 patients suffering from AD with 570 healthy controls. Frequencies of the great majority of KIR genes did not differ between patients and controls, except for KIR2DS1, whose frequency was significantly (OR=0.629, CI95% (0.45; 0.87), pcorr=0.0454) lower in patients than in controls. These results were confirmed in a second cohort of 201 patients. When both patient groups were combined and compared to the control group, the result for KIR2DS1 achieved even higher significance (OR=0.658, CI95% (0.5; 0.86), pcorr=0.0158). To the best of our knowledge, this is the first report on KIR gene contribution to AD, and to allergy in general.