Phenotypic analysis of T-cells in extensive alopecia areata scalp suggests partial tolerance.

This study demonstrates the feasibility and efficacy of using flow cytometric analysis with intracellular cytokine staining for characterization of T-cell phenotype and functional status in extensive alopecia areata (EAA) scalp skin. Cell suspensions were made from scalp punch biopsies taken from 12 patients with long-standing EAA (average disease duration 14 years, 95% hair loss) and six control subjects. EAA samples had a lower percentage of CD-3-expressing cells, but CD-4/CD-8 ratios remained similar to controls.