HMGB1 and toxic epidermal necrolysis: Interestingly, our data also suggest that keratinocyte release of HMGB1 in SJS/TEN skin may occur prior to epidermal detachment (Fig. 4), and thus HMGB1 serum elevation may actually precede it, raising the possibility that it may represent a good early marker of cell death/tissue damage in SJS/TEN.