Objective To investigate the role of interferon γon smooth muscle cells proliferation and migration after balloon injury.
Methods Animal model of rabbit iliac artery balloon injury was set up, smooth muscle cells derived from injured artery were cultured. Smooth muscle cells were divided into four groups ( control, TGF β 1, IFN γ, TGF β 1 and IFN γ).Cells from each group were treated with medium or TGF β 1 (10 ng/ml) and/or IFN γ(500 u/ml) for 72 h separately.
smooth muscle cell proliferation was determined by cell count and MTT, migration of smooth muscle cells was also detected.
Matrix metalloproteinase 2 was also detected by zymography. Results Our results showed that, compared with group control(2.875±0.323×10 5 cells/ml,279.9±8.129 μm), TGF β 1 increased cell count (4.188±0.239×10 5 cells/ml, P <0.01) and migration distance(365.8±9.686 μm , P <0.01), and cell proliferation inhibiting rate of MTT was -19.4% ; whereas IFN γ decreased cell count(1.938±0.249×10 5 cells/ml, P <0.01)and migration distance (234.4±9.722 μm, P <0.01), and cell proliferation inhibiting rate of MTT was 15.8%; TGF β 1 combined with IFN γincreased cell count (3.125±0.254×10 5 cells/ ml, P <0.01) and migration distance(323.1± 8.481μm , P <0.01), but the value was lower than that in cells treated by TGF β 1, proliferation inhibiting rate was -9.1%. Zymography showed that MMP 2 could be detected in all groups, and pro MMP 2 could also be detected in cells treated by TGF β 1. Compared with group control, the relative activity of MMP 2 in cells treated with TGF β 1, IFN γand TGF β 1 together with IFN γ were 143%, 95%, and 109% repectively. Conclusions IFN γ can inhibit smooth muscle cells proliferation and migration and reduce the stimulation of TGF β 1 on smooth muscle cells proliferation and migration. IFN γcan also inhibit MMP 2 activity and lesson the stimulation of TGF β 1 on MMP 2 activity.