HMGB1 and toxic epidermal necrolysis: Our data from skin biopsies also, for the first time, demonstrate that HMGB1 expression is depleted in the epidermis of patients with SJS/TEN, with some HMGB1 being retained in the basal layer, in proximity to the epidermal/dermal junction, providing suggestive evidence of a putative role for HMGB1 in the pathogenesis of epidermal separation, although further work will need to be undertaken to elucidate this.