一种新型可注射细胞治疗载体的初步研究

Preliminary study of a novel injectable cell therapy carrier

目的制备并评估双醛功能化聚乙二醇(difunctionalized polyethylene glycol,DF-PEG)交联乙二醇壳聚糖(glycol chitosan,GCS)复合丝素(silk fibroin,SF)作为一种新型可注射细胞治疗水凝胶载体的可行性。方法室温下将DF-PEG作为交联剂与SF/GCS配比为2∶3的水溶液进行混合,60 s内迅速形成SF/GCS/DF-PEG水凝胶。通过扫描电镜、傅里叶红外光谱(Fourier transform infrared spectroscopy,FT-IR)、X射线衍射(X-ray diffraction,XRD)以及自愈性实验和可注射性实验对SF/GCS/DF-PEG水凝胶的结构和理化特性进行表征。接种小鼠成骨前体细胞(mouse osteoblast progenitor cells,mOPC)并对水凝胶材料的细胞毒性、生物相容性及可注射性进行评价。结果SF/GCS/DF-PEG水凝胶孔隙大小一致、形态规则、孔隙间具有良好的连通性且孔壁厚度均匀、表面光滑。FT-IR及XRD结果表明,凝胶各组分化学基团间发生了相互作用,并伴有结晶状态的改变。包封于水凝胶中的mOPC存活和增殖状态良好,经配有21号注射针头的注射器注射后,0.5与24 h时细胞存活率仍>80%,可耐受水凝胶的包封、注射以及自愈过程。结论成功制备了可注射的自愈性SF/GCS/DF-PEG水凝胶,该水凝胶综合性能优异,有望成为新型可注射型细胞治疗载体。

Objective To prepare and evaluate the feasibility of difunctionalized polyethylene glycol(DF-PEG)-cross-linked silk fibroin/glycolchitosan hydrogelasan inject ablecarrier for cell therapy.Methods DF-PEG was used as a cross-linkingagent,mixed with SF and GCS at room temperature and SF/GCS/DF-PEG hydrogel was generated quickly within 60 s.The structure and physical-chemical properties of the SF/GCS/DF-PEG hydrogel were characterized by scanning electron microscopy,Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),self-healing test and injectability test.Mouse osteoblast progenitor cells(mOPCs)were imbedded into the hydrogel to evaluate the cytotoxicity,biocompati-bility and cell post-injection survival of the hydrogel.Results Electron microscopy showed that SF/GCS/DF-PEG hydro-gel had regular pore size,regular morphology,good connectivity between pores,uniform pore wall thickness,and smooth surface.FT-IR and XRD examination showed that the chemical groups of the gel components interacted with each other and accompanied by changes in the crystalline state.mOPCs survived and proliferated well in hydrogel before and 0.5 and24 h after injection through a 21-gauge needle,indicating that the cells could tolerate the encapsulation,injection and self-healing process of the hydrogel.Conclusion An injectable self-healing and cytocompatible SF/GCS/DF-PEG hydrogel is successfully prepared.The hydrogel has excellent comprehensive properties and is expected to play a role as a new inject-able carrier for cell therapy.