Background
Autoantibodies directed against nucleosomal antigens such as dsDNA and histones are a hallmark of systemic lupus erythematosus (SLE). Histone H1 constitutes the major antigen in LE cell formation and antibodies to H1 have been shown to be more specific for SLE than other anti-histone antibodies [1, 2]. In order to address the role of histone H1-specific T cells in SLE we investigated the ex vivo cellular reactivity to histone antigen in SLE patients and controls, and characterised H1-specific T-cell clones.