095 HLA class II-restricted CD8+ T cells contribute to the promiscuous immune response in dapsone hypersensitive patients

HLA-B*13:01 is associated with dapsone (DDS)-induced hypersensitivity and it has been shown that CD4+ CD8+ T cells are activated by DDS its nitroso metabolite (DDS-NO). However, there a need to define the importance of HLA association in disease pathogenesis. Thus, DDS-NO-specific cell clones (TCC) were generated from hypersensitive patients expressing assessed for phenotype function, HLA-allele restriction, killing target cells. TCC stimulated proliferate secrete effector molecules when exposed and/or DDS-NO. DDS-responsive several DDS-NO-responsive variety TCR sequences displayed class-I-restriction, drug(metabolite) interacting multiple HLA-B alleles. activation certain was inhibited HLA-class-II block, DDS-NO binding HLA-DQB1*05:01. These different origin, but expressed TCRs displaying same amino acid sequences. They via hapten pathway, CD45RO, CD28, PD-1 CTLA-4 surface molecules, secreted panel as class-I-restricted TCC, lower capacity lyse To conclude, interact number activate class-II-restricted display hybrid CD4/CD8 features also contributing promiscuous immune response develops patients.