KIR2DS2/KIR2DL2/HLA-C1 Haplotype Is Associated with Alzheimer's Disease: Implication for the Role of Herpesvirus Infections.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder, where neuroinflammation and immune cells are key pathological factors. Recently, it was suggested a possible association between AD and human herpesvirus 6 (HHV-6) infection. Since we recently observed that multiple sclerosis patients with KIR2DL2 expression on natural killer (NK) cells are more susceptible to herpesvirus infection, we tested the possible implication of KIR/HLA genetic for HHV-6A infection. We identified, for the first time, a possible implication of a specific KIR/HLA subset in AD. The combination KIR2DS2/KIR2DL2/C1 correlated with a lower MMSEDi score, representative of a severe AD status and an increased susceptibility to HHV-6A infection. Therefore, the results seem to converge on the hypothesis that herpesvirus infection might play a role in AD. If this hypothesis finds experimental confirmation, a new therapeutic strategy, modulating KIR2DL2 expression on NK cells, for AD might be envisaged.