[Significance of HLA-DR+ T cells and natural killer (NK) cells in the peripheral blood lymphocytes of alopecia areata (AA)].

HLA-DR+ T cell and NK cell subsets in peripheral blood lymphocytes of patients with AA were investigated. The percentages of HLA-DR+ T cell and NK cell subsets from a mild condition of patchy AA and an acute condition of alopecia totalis, for which hair regrowth occurred frequently with ease, were similar to those of the normal control. On the other hand, the percentages of HLA-DR+ Leu3a+ cells HLA-DR+ Leu2a+ cells and Leu7-Leu11+ cells from a severe condition of patchy AA and alopecia universalis, for which hair regrowth did not easily occur, were significantly higher than those of the normal control. The increase in the percentages of HLA-DR+ Leu3a+ cells, HLA-DR+ Leu2a+ cells and Leu7-Leu11+ cells from the severe condition of patchy AA and alopecia universalis was lessened and normalized by treatment with betamethasone. These findings suggest that the auto-immune disorders of HLA-DR+ T cell and NK cell may play important roles in disease activities related to severe patchy AA and alopecia universalis.