Study On The Pathogenesis Of Drug-specific T Cells In Patients With Severe Drug Eruption

Introduction:Drug eruption is also called drug induced dermatitis, the imflammation of skin or mucos, Severe drug eruption include Sevens-Johnson Syndrome ^ Toxic Epidermal Necrolysis and Exfoliative Dermatitis. It has the feature of rash development, extensive damage of the skin and mucosa, hyperpyrexia, high mortality and the important organs can be involved, but the precise mechanism is not elucidated at present. In recent years,more and more results showed that the pathogenesis of Severe drug eruption is closely related to immunological pathogenesis.ObjectiveDetecting the expression levels of IFN-y secreted by Drug-specific T cells with the presence of causative drugs in vivo. Methods10 cases of patients with serious epispasis were collected. Drawing peripheral blood from patients and separating peripheral blood monouclear cells (PBMCs), PBMCs were stimulated with causative drugs and Drug-specific T cells were acquired. After cultured conventionally, the expression levels of IFN-γsecreted by PBMC detected with ex vivo enzyme-linked immunodotting assay (ELISPOT) ,and Drug-specific T cells were detected with Cultured ELISPOT . At the same time, we make control groups for 10 cases of patients.ResultsPBMCs and Drug-specific T cells in experimental groups(stimulated with causative drugs) secreted more IFN-γcompared with the blank controls(P<0.001). Drug-specific T cells secreted more IFN-γcompared with the PBMC in the same experimental group(P<0.001). The drugs of control groups can not culture the Drug-specific T cells,and the expression levels of IFN-γcan not secreted by PBMC. Moreover, Drug-specific T cells could still be detected in peripheral blood from 3 patients with 1-3 years case history.ConclusionDrug-specific T cells exist in severe drug eruption patients'peripheral blood. The method that Ex vivo ELISPOT associated with Cultured ELISPOT can be applied to sieve causative drugs in vivo. The evidence that Drug-specific T cells can be detected in drug eruption patients'peripheral blood after clinical cure indicates that the causative drugs should be forbidden for a certain time.