title: Examination of tetrachlorosalicylanilide (TCSA) photoallergy using in vitro photohapten-modified Langerhans cell-enriched epidermal cells.
abstract: Lymphocytes from BALB/c mice photosensitized in vivo to tetrachlorosalicylanilide (TCSA) were investigated to determine whether they could be stimulated to proliferate when cultured with Langerhans cell-enriched cultured epidermal cells (LC-EC) photohapten-modified in vitro with TCSA + UVA radiation. Cultured LC-EC were photohapten-modified in vitro by irradiation in TCSA-containing medium using a 1000-watt solar simulator equipped with filters to deliver primarily UVA radiation (320-400 nm). Lymphocytes from TCSA-photosensitized mice were incubated with LC-EC that had been treated in vitro with 0.1 mM TCSA and 2 J/cm2 UVA radiation (TCSA + UVA). Responder lymphocytes demonstrated a significant increase in their blastogenesis response compared to lymphocytes that were incubated with LC-EC irradiated with UVA prior to treatment with TCSA (UVA/TCSA) or with LC-EC that had received no treatment. Lymphocytes from naive mice or mice photosensitized with musk ambrette (MA) demonstrated a significantly lower response to LC-EC modified with TCSA + UVA, indicating the specificity of the response. Maximum blastogenesis response was achieved when LC-EC were treated with 0.1 mM TCSA and a UVA radiation dose of at least 0.5 J/cm2. Epidermal cells depleted of LC by treatment with anti-Ia antibody plus complement or by an adherence procedure were unable to stimulate this blastogenesis response. Epidermal cells treated in vitro with TCSA + UVA demonstrated enhanced fluorescence compared to control cells. The fluorescence observed was not restricted to any specific epidermal cell type; however, fluorescence microscopy studies revealed that dendritic Ia-positive cells, presumably LC, were also TCSA fluorescent. Flow cytometry showed that Ia-positive epidermal cells demonstrated the greatest UV fluorescence when treated with TCSA + UVA compared to both cells irradiated with UVA and subsequently treated with TCSA and untreated cells. This is consistent with the enhanced antigen presentation capability of TCSA + UVA treated LC-EC, which leads to the conclusion that LC photohapten-modified in vitro with TCSA + UVA demonstrate enhanced TCSA fluorescence and are capable of stimulating lymphocytes from TCSA photosensitized mice in an antigen-specific manner.
authors.affiliation: Procter & Gamble Company, Miami Valley Laboratories, Cincinnati, Ohio 45239-8707.
authors.forename: G F
authors.initials: GF
authors.lastname: Gerberick
authors.forename: C A
authors.initials: CA
authors.lastname: Ryan
authors.forename: E C
authors.initials: EC
authors.lastname: Von Bargen
authors.forename: S B
authors.initials: SB
authors.lastname: Stuard
authors.forename: G M
authors.initials: GM
authors.lastname: Ridder
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology; D002478:Cells, Cultured; D003877:Dermatitis, Contact / Q000209:etiology / Q000276:immunology / Q000473:pathology; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D000078404:Epidermal Cells; D004817:Epidermis / Q000276:immunology* / Q000528:radiation effects; D005260:Female; D005434:Flow Cytometry; D006241:Haptens / Q000494:pharmacology*; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007801:Langerhans Cells / Q000166:cytology / Q000276:immunology*; D008213:Lymphocyte Activation / Q000187:drug effects / Q000528:radiation effects; D008214:Lymphocytes / Q000187:drug effects / Q000528:radiation effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008856:Microscopy, Fluorescence; D010787:Photosensitivity Disorders / Q000139:chemically induced / Q000276:immunology / Q000473:pathology*; D012458:Salicylanilides / Q000494:pharmacology*; D014466:Ultraviolet Rays
chemical_list: D000911:Antibodies, Monoclonal; D006241:Haptens; D000949:Histocompatibility Antigens Class II; D012458:Salicylanilides; C003390:3,3',4',5-tetrachlorosalicylanilide