Sustained release of polyethylene glycol-modified hydrogel-packaged growth factors and endothelial progenitor cells

Han Yan-jiu; Liu Guo-hui; Ouyang Liu

doi:10.3969/j.issn.2095-4344.2014.30.015

Abstract：BACKGROUND:Many studies have demonstrated that in order to achieve the endothelialization of the polymer materials, surface loading of bioactive factors is an important means and the introduction of human endothelial cells on the surface of the polymer materials wil contribute to increase the biocompatibility of materials. OBJECTIVE:To synthesize the polyethylene glycol hydrogel packaging vascular endothelial growth factor, basic fibroblast growth factor and endothelial progenitor cells, and to observe the sustained release of growth factors and culture status of endothelial progenitor cells. METHODS:The polyethylene glycol-modified hydrogel containing arginine-glycine-aspartic acid peptide was synthesized, and then, rat endothelial progenitor cells, basic fibroblast growth factor, vascular endothelial growth factor, matrix metal oproteinases were successively added. The hydrogel were immersed in PBS, and ELISA was used to test the levels of growth factors in supernatants every 12 hours. Matrix metal oproteinases-2 (100, 1 000 ng) and matrix metal oproteinases-9 (100, 1 000 ng) at different mass were added into the PBS containing hydrogel after 72 hours. ELISA was also used to test the levels of growth factors in supernatants every 12 hours. The hydrogel encapsulating endothelial progenitor cells was cultured in a culture medium for 5 days, and the number of survival cells was counted by a flow cytometer after digestion. RESULTS AND CONCLUSION:Within 12-72 hours, the release percentage of basic fibroblast growth factor and vascular endothelial growth factor remained at about 41%. After 72 hours, the release percentage of both growth factors was found to grow steadily when matrix metal oproteinases-2 (100, 1000 ng) and matrix metal oproteinases-9 (100, 1 000 ng) at different mass were added, which reached 95%. The release percentage was increased with the increasing mass of matrix metal oproteinases. After 5 days of culture, 88.17%cells stil survived in the hydrogel. These findings indicate that sel-assembly polyethylene glycol-modified hydrogel can realize the control ed release of basic fibroblast growth factor and vascular endothelial growth factor, and it can also support the proliferative growth of endothelial progenitor cells.