Do IL-3/GM-CSF effect on the myofibroblastic differentiation of human adipose derived stromal cells?

BACKGROUND: Capsular contracture is an incurable complication after silicone-based implant surgery. Myofibroblast is the predominant cell in the contracted capsule. We hypothesized that human adipose derive stromal cells (hASCs) together with fibroblast may show a similar phenotypic characteristics of myofibroblast after the treatment of inflammatory cytokines in vitro.

MATERIALS AND METHODS: Interleukin 3 (IL-3) and granulocyte macrophage colony stimulating factor (GM-CSF) were treated in the culture of hASCs and HDFs. Lyn peptide inhibitor was applied as an inhibitor. The changes of cell surface markers (CD105, CD73, CD34, CD45, CD31, CD325 and CD146) were assessed. The expression of various cytokines related to wound contraction were tested such as TGF-β, α-SMA, HGF, FGF, ENT-1, and TSP-1. Myo-D, α-SMA, and glial fibrillary acidic protein (GFAP) were evaluated by blotting and immunocytochemical staining. The collagen-gel contraction assay was performed for the functional contraction of myofibroblastic phenotype.

RESULTS: The expression of α-SMA, Myo-D and GFAP after the treatment of IL-3/GM-CSF showed similar results in hASCs and HDFs. Enhanced expression of TGF- β was observed in HDFs and the increase of ENT-1 and TSP-1 was significant in hASCs. Collagen-gel with HDFs contracted significantly within 24h after the treatment of IL-3/GM-CSF, and the contraction was inhibited by Lyn peptide inhibitor. But in hASCs, the gel-contraction was not significant.

CONCLUSION: IL-3/ GM-CSF effected on the myofibroblastic differentiation of hASCs as well as it did on HDFs. But hASCs did not show the phenotypic gel-contraction within 24h.