T cells in drug allergy.
In recent years, increasing evidence has indicated an important role for T cells in various drug-induced diseases. A detailed analysis of patients with various drug allergies revealed the existence of drug-specific T cells in the circulation or in eluate from skin infiltration in bullous, pustular, and maculopapular drug eruptions. The drug-specific T cells use the ab-T cell receptor CD4+ or CD8+ and react with drugs acting as haptens (covalently bound to larger molecules, such as penicillins), but also recognize drugs if they are bound only in a labile way to major histocompatibility complex molecules (noncovalent drug presentation). Functional analysis revealed a predominant IL-5 production by drug-specific CD4+ T cells in maculopapular exanthema (MPE) and bullous skin diseases, while patients with acute generalized exanthematous pustulosis have a peculiar T cell subset secreting high amounts of IL-8. Moreover, in MPE CD4+, perforin+ T cells were found in vitro and in immunohistology that had cytotoxic potential and killed keratinocytes in vitro and in vivo.
Pichler
Werner J
WJ
Division of Allergology, Clinic for Rheumatology and Clinical Immunology/Allergology, Inselspital, University of Bern, CH-3010 Bern, Switzerland. werner.pichler@insel.ch
D004342:Drug Hypersensitivity / Q000276:immunology*; D005076:Exanthema / Q000139:chemically induced / Q000276:immunology; D006801:Humans; D012872:Skin Diseases, Vesiculobullous / Q000139:chemically induced / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*