HMGB1 and renal fibrosis: In lupus nephritis (LN), HMGB1 also enhances the internalization of anti‐double‐stranded DNA (dsDNA) IgG in MCs by binding to dsDNA IgG and activates the MyD88/NF-κB pathway75, 76, which exhibits a synergistic proinflammatory effect that mediates the activation of MCs77, leading to renal tubular cell death and increased cytokine release78, thereby aggravating proteinuria, glomerulosclerosis, and renal fibrosis in LN76, 79.