用氧化铁磁性纳米颗粒作为基因载体的研究

目的：评价氧化铁磁性纳米颗粒（nanoparticles)作为基因载体的可行性。方法：应用沉淀法制成外包葡聚糖的氧化铁磁性生物纳米颗粒9Dextran Coated Iron Oxide Nanoparticles,DCIONP)。用分光光度计及琼脂糖凝胶电泳分析氧化铁磁性生物纳米颗粒的DNA结合力及抵抗DNASE-Ⅰ消化的作用,以绿色荧光蛋白基因为报道基因,进行用氧化铁磁性纳米颗粒作为基因载体的体外细胞转染实验。结果：电镜检测证实DCIONP的直径在10纳米（nanometer,nm)左右。在酸性条件下,这种纳米颗粒表现出DNA结合力和抵抗DNASE-Ⅰ消化的作用,从而证明DCIONP与DNA的结合是静电引力的作用。在氧化铁磁性生物纳米颗粒表面修饰阳离子聚合物多聚赖氨酸（Dextran Coated Iron Oxide Nanoparticles modified with Poly-L-Lysine,PLL-DCIONP)在中性及碱性的条件下,亦可与带阴性电荷的DNA结合及抵抗DNASE-Ⅰ消化的作用,PLL-DCIONP可作为基因载体将报道基因转染入细胞,用荧光显微镜可观察到发绿色荧光的细胞。在PLL-DCIONP和质粒的质量成一定的比例时,PLL-DCIONP的转染效率高于脂质体。结论：PLL-DCIONP可作为DNA转移载体。     

磁性纳米颗粒在骨转移瘤治疗方面的研究进展

目前肿瘤仍然是困扰骨科界的一大难题,当前的困境主要体现在:①如何早期对恶性肿瘤进行诊断;②化疗药物的全身副作用;③对于癌症晚期和不能接受手术的患者的治疗方案.近年来磁性纳米材料有了长足的发展,其具有的诸多特性正可以解决当前骨科肿瘤医疗与科研中所面临的困境,本文将基于磁性纳米材料的特点系统的对其给予介绍.     

超顺磁性葡聚糖氧化铁纳米颗粒的制备及其作为基因载体的可行性研究

目的磁性纳米颗粒作为基因载体在肿瘤基因治疗中的应用得到了迅速发展。为了能获得驱动目的基因高效稳定表达、安全无害、靶向性高、简便的新型非病毒型基因导入和治疗系统,本研究探讨超顺磁性葡聚糖氧化铁纳米颗粒(superparamagnetic dextran i- ron oxide nanoparticles,SDION)的制备及其作为体外基因载体的可行性。方法采用化学共沉淀法制作SDION,通过丙烯葡聚糖凝胶S-300HR色谱和离心法分离sDl0N,用透射电镜、粒度分析仪和磁力计对SDION进行分析。以绿色荧光蛋白(GFP-C2)质粒为靶基因,通过氧化还原法构建SDION-GFP-C2复合物,用紫外分光光度计和琼脂糖凝胶电泳检测两者的结合率。以脂质体转染作为对照,荧光显微镜分别观察SDION和脂质体体外转染GFP-C2入膀胱癌细胞BIU-87的转染效率。结果SDION直径在3-8 nm之间,有效粒径为59.2 nm,比饱和磁化强度为0.23 emtb,g。分别经10 mmol/L的高碘酸钠氧化、0.5 moL/L的硼氢化钠还原作用后的SDION和GFP的结合比例最大,SDUIN对GFP DNA的转染效率为45%左右,明显高于脂质体的转染效率(30%左右)。结论SIION可通过氧化还原反应与GFP质粒相连,在体外可将GFP基因成功转染入人膀胱癌BIU-87细胞。     

超顺磁性葡聚糖氧化铁纳米颗粒的制备及其作为基因载体的可行性研究(英文)

目的磁性纳米颗粒作为基因载体在肿瘤基因治疗中的应用得到了迅速发展。为了能获得驱动目的基因高效稳定表达、安全无害、靶向性高、简便的新型非病毒型基因导入和治疗系统,本研究探讨超顺磁性葡聚糖氧化铁纳米颗粒(superparamagnetic dextran i-ron oxide nanoparticles,SDION)的制备及其作为体外基因载体的可行性。方法采用化学共沉淀法制作 SDION,通过丙烯葡聚糖凝胶 S-300HR 色谱和离心法分离 SDION,用透射电镜、粒度分析仪和磁力计对 SDION 进行分析。以绿色荧光蛋白(GFP-C2)质粒为靶基因,通过氧化还原法构建 SDION-GFP-C2复合物,用紫外分光光度计和琼脂糖凝胶电泳检测两者的结合率。以脂质体转染作为对照,荧光显微镜分别观察 SDION 和脂质体体外转染 GFP-C2入膀胱癌细胞 BIU-87的转染效率。结果 SDION 直径在3～8nm 之间,有效粒径为59.2nm,比饱和磁化强度为0.23 emu/g。分别经10 mmol/L 的高碘酸钠氧化、0.5mol/L 的硼氢化钠还原作用后的 SDION 和 GFP 的结合比例最大,SDION 对 GFP DNA 的转染效率为45%左右,明显高于脂质体的转染效率(30%左右)。结论 SDION 可通过氧化还原反应与 GFP 质粒相连,在体外可将 GFP 基因成功转染入人膀胱癌 BIU-87细胞。     

超顺磁性葡聚糖氧化铁纳米颗粒的制备及其作为基因载体的可行性研究

背景与目的：磁性纳米颗粒作为基因载体在肿瘤基因治疗中的应用得到了迅速发展。为了能获得驱动目的基因高效稳定表达、安全无害、靶向性高、简便的新型非病毒型基因导入和治疗系统,本研究探讨超顺磁性葡聚糖氧化铁纳米颗粒(superparamapnetic dextran iron oxide nanoparticles,SDION)的制备及其作为体外基因载体的可行性.方法：采用化学共沉淀法制作SDION,通过丙烯葡聚糖凝胶S-300HR色谱和离心法分离SDION,用透射电镜、粒度分析仪和磁力计对SDION进行分析。以绿色荧光蛋白(GFP-C2)质粒为靶基因,通过氧化还原法构建SDION-GFP-C2复合物,用紫外分光光度计和琼脂糖凝胶电泳检测两者的结合率。以脂质体转染作为对照,荧光显微镜分别观察SDION和脂质体体外转染GFP-C2入膀胱癌细胞BIU-87的转染效率。结果：SDION直径在3～8nm之间,有效粒径为59．2nm,比饱和磁化强度为0．23emu／g。分别经10mmol／L的高碘酸钠氧化、0．5mol／L的硼氢化钠还原作用后的sDION和GFP的结合比例最大,sDION对GFPDNA的转染效率为45％左右,明显高于脂质体的转染效率(30％左右)。结论：SDION可通过氧化还原反应与GFP质粒相连,在体外可将GFP基因成功转染入人膀胱癌BIU-87细胞。     

氧化石墨纳米颗粒吸附的5-氟尿嘧啶、抗体和细胞因子的体外生物活性研究

目的 研究氧化石墨纳米颗粒(Graphene Oxide)吸附的化疗药物、抗体和免疫因子体外是否有生物活性。方法 使用氧化石墨纳米颗粒分别吸附5-氟尿嘧啶、干扰素γ和抗白介素10受体抗体,并经光学显微镜、ELISA、Western blot等方法进行检测,在体外验证氧化石墨纳米颗粒吸附的5-氟尿嘧啶、干扰素γ和抗白介素10受体抗体生物学活性。结果 氧化石墨纳米颗粒吸附的5-氟尿嘧啶可以杀死肿瘤细胞并且杀伤效应与剂量呈正相关;氧化石墨纳米颗粒吸附的5-氟尿嘧啶比游离的5-氟尿嘧啶在体外更有效杀死肿瘤细胞;浓度达60 μg/ml氧化石墨纳米颗粒本身不杀死肿瘤细胞,不促进CD11c+树突状细胞表达CD86;氧化石墨纳米颗粒吸附的干扰素γ和抗白介素10受体抗体,可以使LPS刺激的CD11c+树突状细胞分泌更多的白介素12。结论 氧化石墨纳米颗粒吸附的化疗药物和免疫刺激因子体外有生物活性, 有可能成为治疗癌症的新药物。     

ＰＳＭＡ-ＣＡＲ慢病毒颗粒包装浓缩及感染 ＣＩＫ细胞的研究

目的：探讨前列腺特异性膜抗原（ｐｒｏｓｔａｔｅｓｐｅｃｉｆｉｃｍｅｍｂｒａｎｅａｎｔｉｇｅｎ,ＰＳＭＡ） 嵌合抗原受体（ｃｈｉｍｅｒｉｃａｎｔｉｇｅｎ ｒｅｃｅｐｔｏｒ,ＣＡＲ）慢病毒颗粒的浓缩方法及提升感染 ＣＩＫ细胞效率的方法。方法：本研究通过超速离心法、超滤管浓缩 法、ＰＥＧ ８０００浓缩法三种方法浓缩 ＰＳＭＡ ＣＡＲ慢病毒颗粒,通过比较三种方法获得的 ＰＳＭＡ ＣＡＲ慢病毒颗粒感染 ＣＩＫ细胞的效率,确定其最佳浓缩方法;其次,通过比较 ＣＩＫ细胞的感染效率,确定联合室温 ＋长时间 ＋低速离心的 方法是否可以提高 ＰＳＭＡ ＣＡＲ慢病毒颗粒感染 ＣＩＫ细胞的效率。结果：测定 ＰＳＭＡ ＣＡＲ慢病毒颗粒感染 ＣＩＫ细胞 的效率,超滤管浓缩法为 ６．９８％ ±０．７７％,超速离心法为 ３２．０４％ ±１．６６％,ＰＥＧ ８０００浓缩法为 ５３．４７％ ±４．７２％ （Ｆ＝１８９７０,Ｐ＜０．０１）,３种方法的感染效率差异有统计学意义;室温（２６℃）＋长时间（４ｈ）＋低速离心（１５０ｇ）的 方法可使 ＣＩＫ细胞的感染效率提高至 ３２．０４％ ±１．６６％,而常规方法感染 ＣＩＫ细胞的感染效率仅为 ２．７３％ ± ０．７５％。结论：ＰＥＧ ８０００浓缩法为制备 ＰＳＭＡ ＣＡＲ慢病毒颗粒的最佳浓缩方法,室温 ＋长时间 ＋低速离心的方法可 提高其对 ＣＩＫ细胞的感染效率。     

羟基磷灰石纳米颗粒载体介导hGM-CSF基因转染HepG 2细胞及对其生长的影响

目的研究羟基磷灰石(hydroxyapatite,HA)纳米颗粒载体携带人粒-巨噬细胞集落刺激因子(human granulocyte macrophage colony stimulating factor, hGM-CSF)基因转染HepG 2细胞,以及其对细胞生长的影响,为基因修饰的肝癌肿瘤疫苗的临床研究奠定基础.方法采用MTT法检测HA纳米颗粒载体对HepG 2细胞生长的影响;采用HA纳米颗粒载体转染技术,将携带有hGM-CSF基因的表达质粒导入HepG 2细胞中,G 418筛选抗性细胞,限制性稀释法挑选单克隆;RT-PCR法鉴定hGM-CSF的整合和表达,ELISA法测定细胞培养液中的hGM-CSF分泌量和持续的时间;FCM法分析hGM-CSF基因对HepG 2细胞生长的影响.结果MTT结果提示HA纳米颗粒混悬液浓度在80 μg/mL以下对HepG 2细胞生长的影响与对照组比较差异无统计学意义.RT-PCR结果显示hGM-CSF基因在HepG 2细胞中已整合并稳定表达.ELISA检测结果显示转入hGM-CSF基因的HepG 2细胞能稳定分泌hGM-CSF,其分泌量为(216.22± 45.78) ng/106 cells每24 h.FCM检测结果则显示hGM-CSF基因不促进细胞凋亡,且对细胞的生长周期无明显影响.结论HA纳米颗粒载体可以安全地将目的基因hGM-CSF导入HepG 2细胞中且稳定表达,其对细胞的生长无明显影响,为基因修饰的肝癌疫苗的后继研究提供了实验基础.     

介孔二氧化硅纳米载药的特性及其抗骨肉瘤的研究

骨肉瘤(osteosarcoma,OS)是最常见的恶性骨肿瘤,主要好发于青少年。尽管新辅助化疗在一定程度上提高了5年生存率,但静脉注射的化疗药由于疗效不佳、不良反应大使其临床应用受到一定限制。目前介孔二氧化硅纳米粒（mesoporous silica nanoparticles,MSNs）被证明有良好的生物相容性、良好的比表面积及载药空间,可作为抗肿瘤药物载体,靶向治疗骨肉瘤,提高疗效、减轻不良反应,具有很好的应用前景。本文主要分析不同刺激响应的介孔二氧化硅载药系统及其抗骨肉瘤的应用做一综述。     

Composition of PLGA and PEI/DNA nanoparticles improves ultrasound-mediated gene delivery in solid tumors in vivo

The goal of this study was to enhance gene delivery and tumor cell transfection in vivo by using a combination of ultrasonication with complex nanoparticles consisting of two types of nanoparticles: PEI/DNA β-gal plasmid with highly positive zeta-potential and air-filled poly (lactic-co-glycolic acid) (PLGA) particles (with negative zeta-potential) manufactured in our laboratory. The PLGA/PEI/DNA nanoparticles were a colloid with positive zeta-potential and injected i.v. in nude mice with DU145 human prostate tumors. We found that the combination of PLGA/PEI/DNA nanoparticles with ultrasonication substantially enhanced tumor cell transfection in vivo. The overexpression of β-gal gene was evaluated histochemically and by Western blot analysis. At least an 8-fold increase of the cell transfection efficacy was obtained in irradiated tumors compared to non-irradiated controls, while little to no cell death was produced by ultrasonication.     

pH-responsive mesoporous silica nanoparticles employed in controlled drug delivery systems for cancer treatment

In the fight against cancer, controlled drug delivery systems have emerged to enhance the therapeutic efficacy and safety of anti-cancer drugs. Among these systems, mesoporous silica nanoparticles （MSNs） with a functional surface possess obvious advantages and were thus rapidly developed for cancer treatment. Many stimuli-responsive materials, such as nanopartides, polymers, and inorganic materials, have been applied as caps and gatekeepers to control drug release from MSNs. This review presents an overview of the recent progress in the production of pH-responsive MSNs based on the pH gradient between normal tissues and the tumor microenvironment. Four main categories of gatekeepers can respond to acidic conditions. These categories will be described in detail.     

Sustained delivery and efficacy of polymeric nanoparticles containing osteopontin and bone sialoprotein antisenses in rats with breast cancer bone metastasis

Poor prognosis in mammary carcinoma is associated with a certain expression profile of a defined set of genes including osteopontin and bone sialoprotein. Efficient and specific delivery of antisenses (AS) and a protection of the sequences from degradation are the crucial conditions for AS therapeutic efficiency. We hypothesized that effective and safe AS delivery direceted against these genes could be achieved by polymeric nanoparticles (NP) fabricated from a biocompatible polymer. Due to their nano‐size range and small negative charge, AS‐NP can overcome the absorption barrier offering increased resistance to nuclease degradation, sustained duration of AS administration, and consequently, prolonged antisense action. The ASs designed against OPN and BSP‐II were successfully encapsulated in NP composed of the biodegradable and biocompatible polylactide‐co‐glycolide polymer (PLGA), exhibiting sustained release and stability of the ASs. The therapeutic efficacy of the AS‐NP delivery system was examined in vitro, and in a breast cancer bone metastasis animal model of MDA‐MB‐231 human breast cancer cells in nude rats. Treatment with OPN‐AS or BSP‐AS loaded NP in comparison with osmotic mini‐pumps (locoregional injection and SC implants, respectively) resulted in a significant decrease in both, tumor bone metastasis incidence and in the size of the lesions in rats with metastases. Despite its smaller dose, AS‐NP exhibited a better therapeutic efficacy than osmotic mini‐pumps in terms of lesion ratio at later time periods (8–12 weeks). It may be concluded that AS delivery by NP is a promising therapeutic modality providing stability of the encapsulated AS and a sustained release.     

载吲哚菁绿二氧化硅纳米颗粒的构建及其对宫颈癌HeLa细胞的杀伤作用

[摘要] 目的：构建载吲哚菁绿二氧化硅纳米颗粒（ICG@MSNs）并探讨其对宫颈癌HeLa细胞的杀伤作用。方法：通过模板法合成了介孔二氧化硅纳米颗粒（MSNs）,并物理包载光热剂吲哚菁绿（ICG）,制备具有光热效应的ICG@MSNs,并将其应用到HeLa细胞的体外研究中。结果：ICG@MSNs的粒径约200 nm,粒径均一,为形态规则的球形。ICG@MSNs与单纯的ICG具有类似的光热效应。细胞内吞实验显示,ICG包载于二氧化硅纳米颗粒后更易被肿瘤细胞内吞,进而发挥光热作用杀死宫颈癌HeLa细胞;细胞毒性实验表明,在808 nm激光照射下ICG@MSNs对细胞毒性作用明显增加,可以显著杀死宫颈癌HeLa细胞。结论：ICG@MSNs稳定性和生物相容性良好,同时具有良好的产热性能,肿瘤光热治疗效果明显,应用于宫颈癌治疗的前景良好     

Generation 4 polyamidoamine dendrimers is a novel candidate of nano-carrier for gene delivery agents in breast cancer treatment

Polyamidoamine dendrimer (PAMAM-D) is a new gene vector developed in recent years. In this study, we successfully prepared G4PAMAM and detected its unique structure by NMR, FITR and TEM. We revealed that G4PAMAM could bind to human erythrocytes and BSA through electrostatic interaction respectively, and caused haemolysis and reduced bioavailability. However, G4PAMAM-VEGF-ASODN (antisense oligodeoxynucleotides) complex could prevent G4PAMAM from binding to the erythrocytes and BSA and remained stable as a conjugate, therefore the toxicity of the complex was reduced. Meanwhile, we showed that G4PAMAM could be used as a gene vector to deliver AODNs into breast cancer MDA-MB-231 cells without significant cell toxicity, and it enhanced cellular uptake of ODNs. In vivo experiment of human breast tumor xenograft mice model, G4PAMAM also showed more efficiency of accumulating VEGF-ASODN to inhibit the tumor vascularization of breast tumor tissue than naked AODN. Furthermore, G4PAMAM could protect DNA in cytoplasm from digestion of restriction enzymes, which was important to become an effective tool in gene research and therapy.     

Magnetic silica nanocomposites for magnetic hyperthermia applications

This article summarises nearly all magnetic silica nanocomposites that have been synthesised for biomedical applications and evaluated under alternating magnetic field (AMF) from the point of view of heat generation. The use of these nanocomposites as a drug delivery system for remote control of drug release via applying AMF is described. Different parameters that affect the magnetic properties and, therefore, affect the amount of generated heat and the fact that sometimes these parameters are in conflict with each other are discussed. This review article presents insight into the synthesis of nanocomposites with optimal characteristics and use of them in optimal conditions to achieve the optimal magnetic properties for magnetic hyperthermia.     

纳米二氧化硅与肺癌的关系

研究肺癌发生机制并用于指导临床治疗成为迫切的需要。近年研究显示,纳米二氧化硅（纳米SiO2）可能参与细胞损伤、炎症反应、氧化反应、肺的纤维化等机制,与肿瘤的生物学行为密切相关,因此深入研究纳米SiO2与肺癌的关系对肺癌发病机制的研究具有重要意义。     

Convection-enhanced delivery of maghemite nanoparticles: Increased efficacy and MRI monitoring

Convection-enhanced drug delivery (CED) is a novel approach to delivering drugs into brain tissue. Drugs are delivered continuously via a catheter, enabling large volume distributions of high drug concentrations with minimum systemic toxicity. Previously we demonstrated that CED formation/extent of small molecules may be significantly improved by increasing infusate viscosities. In this study we show that the same methodology can be applied to monodispersed maghemite nanoparticles (MNPs). For this purpose we used a normal rat brain model and performed CED of MNPs over short infusion times. By adding 3% sucrose or 3%-6% polyethylene glycol (PEG; molecular weight 400) to saline containing pristine MNPs, we increased infusate viscosity and obtained increased CED efficacy. Further, we show that CED of dextran-coated MNPs (dextran-MNPs) resulted in increased efficacy over pristine MNPs (p < 0.007). To establish the use of MRI for reliable depiction of MNP distribution, CED of fluorescent dextran-MNPs was performed, demonstrating a significant correlation between the distributions as depicted by MRI and spectroscopic images (r(2) = 0.74, p < 0.0002). MRI follow-up showed that approximately 80%-90% of the dextran-MNPs were cleared from the rat brain within 40 days of CED; the rest remained in the brain for more than 4 months. MNPs have been tested for applications such as targeted drug delivery and controlled drug release and are clinically used as a contrast agent for MRI. Thus, combining the CED method with the advantages of MNPs may provide a powerful tool to treat and monitor brain tumors.     

基于二氧化硅纳米粒子的抗肿瘤药物递送系统研究进展CSCD

近年来癌症治疗受到广泛关注,二氧化硅纳米颗粒因其独特的理化性质在肿瘤诊疗领域展现巨大潜力。基于二氧化硅纳米粒子的药物输送系统可被动或主动靶向肿瘤组织,并通过刺激响应的方式实现药物在肿瘤部位的可控释放,有效提高抗肿瘤药物在肿瘤部位的浓度,提高治疗效率。同时,二氧化硅纳米粒子通过负载造影剂可实现生物成像功能,用于肿瘤组织定位及药物追踪,实现更高效的抗肿瘤治疗。本文介绍了二氧化硅纳米粒子的制备方式,并对二氧化硅纳米粒子在药物靶向递送系统及生物成像领域中的研究进展进行综述。