Significance of HLA-DR+ T Cells and Natural Killer Cells in the Peripheral Blood Lymphocytes of Alopecia Areata

The study investigated HLA-DR+ T cell and NK cell subsets in patients with alopecia areata (AA). It found that patients with mild patchy AA and acute alopecia totalis had similar cell percentages to normal controls, while those with severe patchy AA and alopecia universalis had significantly higher percentages of HLA-DR+ Leu3a+, HLA-DR+ Leu2a+, and Leu7-Leu11+ cells. Treatment with betamethasone normalized these elevated cell percentages. The findings suggested that autoimmune disorders involving HLA-DR+ T cells and NK cells played important roles in severe AA and alopecia universalis.