Adipose-Derived Stem Cell Exosomes Inhibit Hypertrophic Scaring Formation by Regulating Th17/Treg Cell Balance

Aiming to reveal the role of ADCS-Exos in secretion of inflammatory factors, Th17 and regulatory T (Treg) cell differentiation from naive CD4+ T cells in hypertrophic scaring formation and maturation is explored. ELISA, qRT-PCR, and immunoblotting are performed to assay the local inflammatory factors IL-6, IL-10, IL-17A, and TNF-alpha, and transcriptional factors of ROR Upsilon t and Foxp3, in scaring tissue from patients and mice wound models treated with or without ADCS-Exos. Immunohistochemistry staining and immunoblotting are conducted to assay the extracellular matrix (ECM) deposition in vitro and in vivo. The results show that IL-6, IL-10, IL-17A, TNF-alpha, ROR Upsilon t, and Foxp3 are increased on mRNA and protein levels in hypertrophic scaring compared with atrophic scaring and normal skin. Naive CD4(+) T cells treated with ADCS-Exos in vitro can produce significantly less IL-6, IL-17A, TNF-alpha, and ROR Upsilon t and more IL-10 and Foxp3 on mRNA and protein levels. In addition, mice in ADSGExos-treated group demonstrate less collagen deposition; decreased IL-17A, TNF-alpha, and ROR Upsilon t; and increased IL-10 and Foxp3 production.

Automated summary

This study investigates the role of ADCS-Exos in the secretion of inflammatory factors, Th17 and Treg cell differentiation in hypertrophic scar formation and maturation. The results show that hypertrophic scars have increased levels of IL-6, IL-10, IL-17A, TNF-alpha, ROR ut, and Foxp3. Naive CD4(+) T cells treated with ADCS-Exos exhibit decreased production of IL-6, IL-17A, TNF-alpha, and ROR ut, and increased production of IL-10 and Foxp3. Mice treated with ADCS-Exos also show reduced collagen deposition and increased production of IL-10 and Foxp3.