Potency classification of topical corticosteroids: modern perspectives.

The effects of topical corticosteroid therapy upon human epidermal Langerhans cell surface markers were studied. The reduction in numbers of human leukocyte antigen-DR+/T6+ Langerhands cells proved to be a potency-related effect and Langerhans cell enumeration may therefore have some use as an adjunct in the assessment of steroid potency. Further studies showed that corticosteroid therapy also reduced the function of Langerhans cells in terms of epidermal cell alloantigen-presenting capacity. However, experimental variation and the high antigen-presenting potency of residual flow cytomterically sorted human leukocyte antigen-DR+/T6+ Langerhans cells following steroid application (1) mean that such functional assessments of epidermal cell alloantigen-presenting capacity cannot be recommended as an easily reproducible method for measuring steroid potency.