title: Immunophenotyping of the eczematous flare-up reaction in a nickel-sensitive subject.
abstract: An eczematous flare-up reaction, occurring at a previously involved site, which followed oral challenge with 5.6 mg of nickel in a 29-year-old nickel-sensitive woman, was biopsied and studied by immunohistochemistry. The cellular infiltrate in the dermis and epidermis at 8 days was predominantly of Leu 3a phenotype (helper/inducer T lymphocytes), with smaller numbers of Leu-2a-reactive (suppressor/cytotoxic) T lymphocytes. Many infiltrating cells were DR-positive. No increase in epidermal Leu-6-positive Langerhans cells was seen but Leu-6-reactive cells were noted in the dermal infiltrate. Keratinocytes showed some expression of class II antigen (mainly DR). In comparison with the 48-hour allergic patch test reaction, the eczematous flare-up site showed no increase in epidermal Langerhans cell numbers nor infiltration with macrophages, but the responses were similar since both showed a superficial T cell reaction in the skin.
mesh_terms: D000328:Adult; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D004485:Eczema / Q000276:immunology; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D006801:Humans; D006967:Hypersensitivity / Q000276:immunology*; D007801:Langerhans Cells / Q000276:immunology; D009532:Nickel / Q000009:adverse effects*; D010641:Phenotype
chemical_list: D000945:Antigens, Differentiation, T-Lymphocyte; D000949:Histocompatibility Antigens Class II; D009532:Nickel