两亲性含IKVAV的肽体内诱导血管生成的研究

Research on Angiogenesis Induced with IKVAV-containing Amphiphile Peptide in Vivo

目的设计合成含IKVAV的两亲性肽,探讨其体外自组装成三维多孔凝胶及体内诱导血管生成的可行性。方法同相法合成肽,自组装成凝胶,TEM观察凝胶结构。实验组:配制1 wt%的肽溶液,pH值为9.0;对照组:配制16.67%的明胶,pH值为7.4。各取1 mL,分别注射于大鼠脊柱两侧皮下,术后1周观察全身反应及局部皮肤。2周后取材,固定,常规HE染色及VEGF免疫组织化学染色。结果高效液相频谱仪及质谱仪示肽纯度及分子量分别为95.22%与1 438,TEM示凝胶为交织成网状的纳米纤维。术后1周动物存活良好,无全身不良反应.局部皮肤无红肿、无坏死。实验组:1 wt%的肽体内自组装成凝胶,血管长入凝胶内部.管腔内可发现红细胞;术后2周,VEGF阳性。对照组:明胶内未发现血管,VEGF阴性。结论本实验合成含IKVAV两亲性肽,在PBS溶液中可自组装成凝胶且体内可诱导新生血管生成。

Objective The amphiphile peptide containing IKVAV sequence was fabricated and subcutaneously implanted into rat backbone. The angiogenesis induced with peptide in vivo were explored. Methods The peptide was synthesized and self-assembled into hydrogel whose structure was confirmed with TEM. 1 millilitre of 1% peptide （EG） and 16.67% gelatin （CG） were injected subcutaneously beside rat backbone. The systemic response and local skin were observed one week after injection. The specimens were harvested two weeks later and immunohistochemically examined for VEGF. Results Peptide molecular weight was 1 438 and purity was 95.22%, as confirmed by MS and HPLC respectively. TEM showed that hydrogel was composed of interconnected nanofibers. The inflammatory reaction and necrosis of local skins were not found one week after injection. Light microscope showed that lots of capillary vessels with complete wall. Erythrocytes were noted inside the vessels in the experimental group （EG）; The capillary vessels or erythrocytes were not found in the gelatin in the control group （CG）. The immunohistochemical detection revealed VEGF-positive cells in EG, which were not found in CG. Conclusion The self-assembly hydrogel from IKVAV-containing peptide was able to induce the angiogenesis in vivo.