Gray J L, Kang S S, Zenni G C, Kim D U, Kim P I, Burgess W H, Drohan W, Winkles J A, Haudenschild C C, Greisler H P
Department of Surgery, Loyola University Medical Center, Maywood, IL 60153.
J Surg Res. 1994 Nov;57(5):596-612. doi: 10.1006/jsre.1994.1189.
The affixation of FGF-1 to porous vascular grafts has been reported to stimulate capillary ingrowth and surface endothelialization. The current study further characterizes responses to fibroblast growth factor (FGF)-1 affixation to 30-cm-long grafts followed 140 days. ePTFE grafts (30 cm x 8 mm i.d.), 60 microns internodal distance, were impregnated with fibrin glue (FG) suspensions containing FGF-1 and heparin. Two negative control groups were treated either with FG with heparin alone or left untreated. Grafts were explanted from the canine thoracoabdominal aortic position after 10, 30, or 140 days (n = 3/time/group) 10 hr after im injection of tritiated thymidine (0.5 muCi/kg). Specimens were studied by light and electron microscopy, immunohistochemistry, morphometric analyses, and cross-sectional autoradiography. RNA preparations from inner capsule tissues were used for reverse transcription-polymerase chain reaction (RT-PCR) analyses of FGF-1, FGF-2, transforming growth factor-beta 1, (TGF-beta 1) and FGF receptor mRNA species. Inner capsule collagen was quantitated by hydroxyproline colorimetry. Histologic analyses of perianastomotic regions were performed for comparison purposes. All explants were patent and without intimal hyperplasia. Progressive capillarization of the internodal spaces occurred over time and was significantly more extensive in the FGF-1-treated group. Endothelialization of the luminal surface increased with time, at 140 days covering 86.7 +/- 11.6% of the FGF-1 explants vs 46.1 +/- 7.5% and 48.1 +/- 13.3% in the other groups, P < 0.007 and P < 0.04, respectively. Inner capsule thickness at 140 days differed significantly (P < 0.05) between the FGF-1 group (138.8 microns) vs either control group (93 and 67 microns, respectively), which did not significantly differ from each other. Cross-sectional autoradiography demonstrated an FGF-1-induced mitotic index increase at 30 days, 9.6 +/- 4.4% compared to 2.5 +/- 1.0 and 0 +/- 0%, respectively, with both myofibroblasts and endothelial cells incorporating the [3H]thymidine label. The mitotic index returned to quiescent levels at 140 days (< 1% in all groups). Collagen content increased with time in all groups, significantly greater in both FG groups vs untreated controls at 30 and 140 days. RT-PCR analyses revealed FGF-1, FGF-2, FGFR-1 (flg), and TGF-beta 1 mRNA in all samples without evidence of modulation by FGF-1 affixation. These data demonstrate FGF-1-induced graft capillarization and surface endothelialization without functionally significant intimal hyperplasia in this model.
据报道，将成纤维细胞生长因子-1（FGF-1）附着于多孔血管移植物可刺激毛细血管向内生长和表面内皮化。本研究进一步描述了在140天内，对30厘米长的移植物附着FGF-1后的反应特征。内径8毫米、节距60微米的膨体聚四氟乙烯（ePTFE）移植物用含有FGF-1和肝素的纤维蛋白胶（FG）悬浮液浸渍。两个阴性对照组分别单独用含肝素的FG处理或不做处理。在注射氚标记胸腺嘧啶核苷（0.5μCi/kg）10小时后，于10天、30天或140天（每组每次n = 3）从犬胸腹主动脉位置取出移植物。通过光镜和电镜、免疫组织化学、形态计量分析和横断面放射自显影对标本进行研究。来自内囊组织的RNA制剂用于FGF-1、FGF-2、转化生长因子-β1（TGF-β1）和FGF受体mRNA种类的逆转录-聚合酶链反应（RT-PCR）分析。通过羟脯氨酸比色法对内囊胶原蛋白进行定量。为了进行比较，对吻合口周围区域进行组织学分析。所有取出的移植物均通畅且无内膜增生。随着时间推移，节间空间逐渐出现毛细血管化，且在FGF-1处理组中更为广泛。管腔表面的内皮化随时间增加，在140天时，FGF-1处理的移植物内皮化覆盖面积为86.7±11.6%，而其他组分别为46.1±7.5%和48.1±13.3%，P分别<0.007和<0.04。140天时，FGF-1组的内囊厚度（138.8微米）与两个对照组（分别为93微米和67微米）相比有显著差异（P<0.05），而两个对照组之间无显著差异。横断面放射自显影显示，在30天时FGF-1诱导有丝分裂指数增加，分别为9.6±4.4%，而其他两组分别为2.5±1.0%和0±0%，肌成纤维细胞和内皮细胞均掺入了[3H]胸腺嘧啶核苷标记。在140天时，有丝分裂指数恢复到静止水平（所有组均<1%）。所有组的胶原蛋白含量均随时间增加，在30天和140天时，两个FG组的胶原蛋白含量均显著高于未处理的对照组。RT-PCR分析显示，所有样本中均有FGF-1、FGF-2、FGFR-1（flg）和TGF-β1 mRNA，且未发现FGF-1附着有调节作用的证据。这些数据表明，在该模型中，FGF-1可诱导移植物毛细血管化和表面内皮化，且无功能上显著的内膜增生。
