Adipose-derived stem cells inhibit dendritic cell migration by secreting tumor necrosis factor-α-stimulated gene 6 to improve the allogeneic skin transplantation survival rate in mice

Allogeneic skin transplantation faces significant immunological challenges due to immune rejection, primarily mediated by dendritic cells (DCs). Adipose-derived stem cells (ADSCs) possess immunomodulatory effects; however, the underlying molecular mechanisms in regulating DC function remain unclear. This study aimed to investigate the regulatory effects of ADSCs and tumor necrosis factor-α-stimulated gene 6 (TSG-6) secreted by ADSCs on DC in the murine allogeneic skin transplantation. Following transplantation, recipients received ADSCs, TSG-6 knockdown ADSCs (ADSCs-shTSG-6), or control treatments. Immune cell infiltration and cytokine expression were analyzed by flow cytometry and immunohistochemistry. Transwell assays were used to assess the effect of TSG-6 on DCs migration. TSG-6-related gene expression profiles were explored using transcriptomic analysis and validated by RT-qPCR. ADSC treatment significantly reduced the migration of DCs to the recipient than the ADSCs-shTSG-6 treatment, while reducing the levels of macrophages, lymphocytes, and pro-inflammatory cytokines. ADSC-derived TSG-6 inhibited DCs migration, an effect diminished upon TSG-6 knockdown and restored by TSG-6 supplementation. Transcriptomic analysis identified a panel of immune-related genes (ADM, GHRH, SELENBP1, NDRG1) regulated by TSG-6. These findings indicate that ADSCs enhance graft tolerance by inhibiting DCs migration via TSG-6 secretion, highlighting TSG-6 as a promising therapeutic target for preventing transplant rejection.