title: Macrophage-T lymphocyte relationships in man's contact allergic reactions.
abstract: Seventeen biopsies from contact allergic reaction sites in sensitized patients were studied by electron microscopy and immunocytochemistry. Very intimate appositions of macrophages to T lymphocytes were frequently observed in the dermis at 6, 8 and 12 hours after application of the allergen. Such juxtapositions were seen less frequently after 24, 48 and 72 hours. These appositions seem to indicate that macrophages play an antigen-presenting role in human contact allergic reactions, as Langerhans cells seem to do.
mesh_terms: D000485:Allergens / Q000276:immunology; D002462:Cell Membrane / Q000648:ultrastructure; D003877:Dermatitis, Contact / Q000276:immunology* / Q000473:pathology; D006801:Humans; D007124:Immunoenzyme Techniques; D008264:Macrophages / Q000276:immunology* / Q000648:ultrastructure; D008854:Microscopy, Electron; D013601:T-Lymphocytes / Q000276:immunology* / Q000648:ultrastructure; D013997:Time Factors
chemical_list: D000485:Allergens