title: Metabolic and chemical origins of cross-reactive immunological reactions to arylamine benzenesulfonamides: T-cell responses to hydroxylamine and nitroso derivatives.
abstract: Exposure to sulfamethoxazole (SMX) is associated with T-cell-mediated hypersensitivity reactions in human patients. T-cells can be stimulated by the putative metabolite nitroso SMX, which binds irreversibly to protein. The hydroxylamine and nitroso derivatives of three arylamine benzenesulfonamides, namely, sulfamethozaxole, sulfadiazine, and sulfapyridine, were synthesized, and their T-cell stimulatory capacity in the mouse was explored. Nitroso derivatives were synthesized by a three-step procedure involving the formation of nitro and hydroxylamine sulfonamide intermediates. For immune activation, female Balb-c strain mice were administered nitroso sulfonamides four times weekly for 2 weeks. After 14 days, isolated splenocytes were incubated with the parent compounds, hydroxylamine metabolites, and nitroso derivatives to measure antigen-specific proliferation. To explore the requirement of irreversible protein binding for spleen cell activation, splenocytes were incubated with nitroso derivatives in the presence or absence of glutathione. Splenocytes from nitroso sulfonamide-sensitized mice proliferated and secreted interleukin (IL)-2, IL-4, IL-5, and granulocyte monocyte colony-stimulating factor following stimulation with nitroso derivatives but not the parent compounds. Splenocytes from sensitized mice were also stimulated to proliferate with hydroxylamine and nitroso derivatives of the structurally related sulfonamides. The addition of glutathione inhibited the nitroso-specific T-cell response. Hydroxylamine metabolites were unstable in aqueous solution: Spontaneous transformation yielded appreciable amounts of nitroso and azoxy compounds as well as the parent compounds within 0.1 h. T-cell cross-reactivity with nitroso sulfonamides provides a mechanistic explanation as to why structurally related arylamine benzenesulfonamides are contraindicated in hypersensitive patients.
authors: MRC Centre for Drug Safety Science, Department of Pharmacology and Therapeutics,The University of Liverpool, Liverpool L69 3GE, United Kingdom.
authors: J Luis
authors: JL
authors: Castrejon
authors: Sidonie N
authors: SN
authors: Lavergne
authors: Ayman
authors: A
authors: El-Sheikh
authors: John
authors: J
authors: Farrell
authors: James L
authors: JL
authors: Maggs
authors: Sunil
authors: S
authors: Sabbani
authors: Paul M
authors: PM
authors: O'Neill
authors: B Kevin
authors: BK
authors: Park
authors: Dean J
authors: DJ
authors: Naisbitt
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D019811:Hydroxylamine / Q000737:chemistry / Q000378:metabolism*; D007376:Interleukin-2 / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D015848:Interleukin-5 / Q000378:metabolism; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D009603:Nitroso Compounds / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D013420:Sulfamethoxazole / Q000031:analogs & derivatives / Q000276:immunology / Q000378:metabolism; D013424:Sulfanilamides / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000890:Anti-Infective Agents; D007376:Interleukin-2; D015848:Interleukin-5; D009603:Nitroso Compounds; D013424:Sulfanilamides; D015847:Interleukin-4; D019811:Hydroxylamine; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D013420:Sulfamethoxazole