RESUMO
Objective:To investigate the effect of keloid fibroblasts on the polarization and expression of inflammatory factors of M0 macrophages and possible mechanisms, and provide theoretical basis for new targets for keloid therapy.Methods:Keloids, normal skin tissues and paraffin specimens from patients undergoing plastic surgery in the First Affiliated Hospital of Sun Yat-sen University from November 2020 to September 2021 were collected, and fibroblasts of keloids and normal skins were isolated and co-cultured with M0 cells formed form THP-1 by phorbol ester (PMA)-stimulation to detect the expression of macrophage polarization markers and cytokines. Besides, keloid fibroblasts were treated with exogenous tumor necrosis factor-α(TNF-α) to detect its effect on the proliferation and extracellular matrix expression.Results:Macrophages were dominated by CD163 + (M2) in keloid tissues. Moreover, M0 cells expressed more TNF-α when co-cultured with keloid fibroblasts, compared with those with normal skin fibroblasts, in which, the positive staining rates of TNF-α were 19.32% and 29.52% respectively by flow cytometry. Furthermore, the proliferation was promoted and the expression of extracellular matrix proteins (COL3A1 and FN1)and Vimentin were upregulated in keloid fibroblasts under TNF-α stimulation. However, there was no significant difference in the expression of polarization surface markers CD86 and CD163 in macrophages, when co-cultured with keloid fibroblasts or normal skin fibroblasts. Conclusions:Keloid fibroblasts promote the expression of TNF-α in macrophages, which in turn promotes the proliferation and extracellular matrix secretion of keloid fibroblasts.