Herceptin介导的肿瘤靶向治疗用免疫磁性纳米微粒的制备

Preparation of immunomagnetic nanoparticles for tumor targeting therapy with herceptin

目的制备人源性单抗Herceptin介导的靶向HER-2/neu癌基因的免疫磁性纳米微粒。方法采用部分还原沉淀法制备四氧化三铁磁微粒子,并用硅烷偶联剂进行表面修饰,利用戊二醛作为交联剂,将单抗Herceptin与磁性纳米微粒进行交联构建免疫磁性纳米微粒。用扫描电镜(SEM)、X-射线粉晶衍射(XRD)、磁强计(VSM)、X射线能谱仪(EDS)等分析仪器对磁性纳米微粒的特性进行表征,并对免疫磁性纳米微粒的免疫活性进行测定。结果磁性纳米微粒经表面硅烷修饰后平均粒径在20nm左右,磁饱和强度为65emu/g。磁性纳米微粒表面经氨基官能团化后,表面氨基密度为0.5μmol/mg,固载有组氨酸的磁性纳米微粒与人源性单抗Herceptin偶联后平均粒径在60nm左右,且保持较好的Herceptin的免疫结合活性。结论通过化学偶联方法将针对HER-2/neu癌基因的人源化单抗Heceptin固定在磁性纳米微粒的表面,可满足进一步的肿瘤靶向治疗的要求。

Objective To prepare immunomagnetic nanoparticles（IMNs） for HER2/neu-targeted radioimmunotherapy with herceptin,a humanized anti-p185-HER-2/neu monoclonal antibody targeting the extracellular domain of HER-2/neu receptor.Methods The magnetic nanoparticles were synthesized by partial reductive precipitation method and the surface of the particles was chemically modified using silane coupling agent.Herceptin and histidine were covalently linked to the amine group upon the silica-coated magnetic nanoparticles modified by N-[3-（trimethyoxysilyl） propyl]-ethylenediamine using glutaraldehyde method to prepare the IMNs.The nanoparticles were evaluated by diffraction（XRD）,scanning electron microscope（SEM） and X-ray energy spectrometry（EDS）,and the immunoreactivity of IMN was determined.Results The average diameter of the decanioc acid-coated Fe3O4 nanoparticle was about 20 nm with a magnetic saturation of 65 emu/g.The surface amino group was 0.5 μmol/mg after modification with the amid functional group,and the mean size of Herceptin-loaded IMNs was about 60 nm.The IMN retained good immunoreactivity of Herceptin.Conclusion The IMNs exhibit good properties for potential application in tumor targeting therapy using Herceptin against HER-2/nue proto-oncogene.