“High mobility group box 1” (HMGB1) is a well-known nuclear protein that stabilizes DNA and facilitates gene transcription. Recently, we confirmed that HMGB1 shows the proinflammatory activity depending on the redox status, which is in the reduced, disulfide, or oxidized form in keratinocyte (Mori H. et al., JDS2018). In addition, reduced-HMGB1 showed the suppressive effect of poly(I:C)-induced inflammation (Mori H. et al, JDS2018). On the other hand, HMGB1 contains two homologous DNA-binding domains, the A and B-boxes. HMGB1 B-box induces strong proinflammatory activities, but HMGB1 A-box is a specific antagonist for HMGB1 and exerts an anti-inflammatory effect in macrophage. However, the direct effects of HMGB1 A-box and B-box for keratinocytes were not well elucidated. To investigate those effects, we established recombinant peptides for HMGB1 A-box and B-box.

Suppressive effect of HMGB1 A-box for inflammation in keratinocytes.