Interleukin-2 receptor in peripheral blood lymphocytes of Alzheimer's disease patients.

In this study, we investigated the differences in the incidence rate of human leukocyte antigen-DR (HLA-DR) and interleukin 2 receptor (IL-2R) in the peripheral blood lymphocytes of 13 women who were diagnosed clinically as having Alzheimer's disease (AD group), and 13 healthy women with no mental disorders (control group). As a result, the AD group showed a markedly higher rate of lymphocyte subsets of CD4+HLA-DR+, CD4+IL-2R+, CD8+HLA-DR+, CD8-HLA-DR+ and CD8+IL-2R+. This finding indicates a possible immune reaction occurring in the peripheral blood of AD patients. In addition, these higher rates correlate well with the changes in the immune system reported in the postmortem brains of AD patients. Our findings indicate that immunological interactions exist between the central nervous system and the peripheral blood lymphocytes of AD patients, and AD might be induced by an immune reaction occurring in the brain.