FIGURE 4. Endovascular cell therapy increases TIMP expression. RT-PCR comparative to the domestic gene 18s for TIMP-1, -2, and -3 in VSMCs in culture, before seeding, and in vivo (intima, and media plus adventitia) one week after the endovascular treatment (A). The expression of TIMP-1 and -3 increased in the intima of dilated aortas after treatment (VSMC+), demonstrating that the seeded VSMCs produce high amounts of MMP inhibitors. Reverse zymography (B) shows TIMP activity as dark bands. TIMP-3 was detected in the media and adventitia. □, Dilated aortas infused with culture medium as a control (VSMC−); ▪, dilated aortas seeded with VSMCs (VSMC+). Lanes 1 and 3: intima or thrombus; lanes 2 and 4: media plus adventitia. Reverse zymography was performed with extracts from 3 grafts, pooled by group. RT-PCR data were generated from pools of 3 grafts in each group for each layer.