title: The effects of topical treatment with steroids or dithranol on epidermal T lymphocytes and dendritic cells in psoriasis.
abstract: We describe the effects of treatment with topical steroids or dithranol on T and dendritic cells in the skin of patients with chronic plaque psoriasis. Resolution of lesions by both types of topical treatments was accompanied by a marked decrease in epidermal T cells. In steroid treated lesions there was also a reduction in DR+ dendritic cells to normal numbers during treatment and the rate of disappearance of both cell types correlated with the rate of resolution. However, a significant reduction of dendritic cells was not usually observed until after the T cells had almost disappeared from the epidermis and substantial healing of lesions had taken place. Dendritic cells in steroid-treated uninvolved skin had decreased to a lower level than in normal skin. In contrast, dithranol did not affect dendritic cells, either in lesional or in unaffected psoriatic epidermis. The decrease in dermal T cells observed with both treatments was more marked in steroid-treated lesions and correlated with resolution. However, blood T cells were unaffected by both treatments. The findings provide further support for the role of T cells in the pathogenesis of psoriasis.
mesh_terms: D000287:Administration, Topical; D000873:Anthracenes / Q000494:pharmacology*; D000875:Anthralin / Q000494:pharmacology* / Q000627:therapeutic use; D000938:Antigen-Presenting Cells / Q000187:drug effects / Q000276:immunology*; D002990:Clobetasol / Q000031:analogs & derivatives / Q000494:pharmacology / Q000627:therapeutic use; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D006801:Humans; D007958:Leukocyte Count; D011565:Psoriasis / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology; D012867:Skin / Q000473:pathology; D013601:T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000032:analysis; D050378:T-Lymphocytes, Regulatory / Q000032:analysis
chemical_list: D000873:Anthracenes; D006684:HLA-DR Antigens; D000949:Histocompatibility Antigens Class II; D002990:Clobetasol; D000875:Anthralin