ABSTRACT
The purpose of this study is to investigate the effect of interferon-gamma (IFN-gamma) on myofibroblast generation using four myofibroblast cell lines that we established from Dupuytren's nodules. Cells were cultured in Earl's medium with 15% fetal bovine serum (FBS) and plated on a microplate at a density of 10(4) cells/well. These cells were treated with various concentrations of IFN-gamma (0-1000 U/mL) for 3 days. By cell-capture enzyme immunoassay (CC-EIA), immunofluorescence staining, and reverse transcriptase polymerase chain reaction (RT-PCR) analysis, we evaluated the effect of IFN-gamma on the expression of alpha smooth muscle actin (alphaSMA) in these cells. CC-EIA and RT-PCR analysis showed that IFN-gamma suppressed alphaSMA expression, and immunofluorescence microscopy demonstrated that IFN-gamma markedly decreased the number of alphaSMA-positive cells. These results showed that IFN-gamma strongly inhibits myofibroblast generation in established myofibroblast cell lines and suggest the possibility of using IFN-gamma therapy for contractile disease.
Subject(s)
Actins/metabolism , Fibroblasts/drug effects , Fibroblasts/metabolism , Interferon-gamma/pharmacology , Muscle, Smooth/metabolism , Actins/genetics , Cell Line , Dose-Response Relationship, Drug , Fibroblasts/cytology , Gene Expression Regulation/drug effects , Humans , Muscle, Smooth/drug effects , RNA, Messenger/genetics , RNA, Messenger/metabolismABSTRACT
Interferon gamma (IFNgamma) has been reported as a possible therapeutic agent for contractile diseases in clinical trials and in vitro studies. It is not yet clear, however, whether IFNgamma simply inhibits myofibroblast generation or downregulates alpha smooth muscle actin (alphaSMA) production in myofibroblasts. In this study, we attempted to clarify how IFNgamma acts in the generation of myofibroblasts, and the production of alphaSMA by myofibroblasts, using immunofluorescence staining, cell capture enzyme immunoassay (CC-EIA) and the reverse transcription polymerase chain reaction (RT-PCR) for alphaSMA. We examined whether IFNgamma could block the TGFbeta1-promoted changes in myofibroblasts or the generation of myofibroblasts by TGFbeta1. IFNgamma strongly blocked the generation of myofibroblasts and moderately inhibited the production of alphaSMA in TGFbeta1-promoted myofibrobasts. These findings indicate that IFNgamma may be effective in the early stage of contractile diseases to prevent the progression of contractile lesions.