近红外下光敏脂质体触发阿霉素的释放的研究与应用

发布时间：2018-01-20 05:52

本文关键词： 中空金纳米颗粒热敏脂质体光热效应触发释放免疫脂质体主动靶向治疗　出处：《浙江大学》2014年硕士论文　论文类型：学位论文

【摘要】：脂质体是药物传递研究领域最好的药物载体类型之一,然而,控制被包裹的药物在特定的空间和时间上从脂质体中释放出来依然是一个亟待解决的难题。光热消融(PTA)是一种采用近红外(NIR)激光产热来杀伤肿瘤细胞的技术；该技术在肿瘤治疗上展现了良好的临床应用前景。但是,仅仅通过PTA治疗很难彻底地根治肿瘤,因为热量分布的不均匀导致肿瘤的部分区域的热量低于杀伤热剂量。在本研究中,我们制备了一种新型的热敏脂质体,又称光敏脂质体。该载药脂质体含有中空金纳米颗粒(hollow gold nanospheres, HAuNS)和阿霉素(doxorubicin,DOX)。中空金纳米颗粒(hollow gold nanospheres, HAuNS),其粒径为35.6±1.7nm,多分散系数PI为0.003。近红外下具备良好的表面等离子共振(surface plasmon resonance)光学特性,可以吸收近红外光并产生热量。透射电子显微镜结果已经验证,HAuNS经疏水性修饰后,可以粘附在热敏脂质膜上。在NIR激光照射条件下,光敏脂质体展现了光热效应,还可以控制药物释放。我们的实验结果表明,NIR激光照射条件下,DOX从光敏脂质体(DOXHAuNS-TSL)中快速且持续地释放出来。在体外的释放研究中,NIR照射下,24h内,DOX从DOXHAuNS-TSL中的累积释放量提高了近40%；而无NIR照射下,24h内,DOX从DOXHAuNS-TSL中的累积释放量不超过6%。主要是由于疏水性的HAuNS粘附在脂质膜上,吸光产热,升高的温度达到脂质体的相转变温度进而提高了脂质膜的通透性。我们的数据也表明,较之单一的DOXHAuNS-TSL,单一的DOX-TSL,或者HAuNS-TSL结合NIR激光照射；采用DOXHAuNS-TSL结合NIR激光照射,呈现更为显著的细胞毒性。主要由以下三方面作用造成：1)光热消融(PTA)效应,2)DOX从DOXHAuNS-TSL中的触发导致细胞内的药物浓度增加,3)光热效应和DOX药物作用的联合作用。而且,体内抗肿瘤研究结果表明,由DOXHAuNS-TSL结合NIR激光照射介导的光热和化学治疗联合效应,较之由HAuNS-TSL结合NIR激光照射介导的光热消融(PTA)效应,展现更显著彻底的抗肿瘤效果。揭示在肿瘤的PTA临床应用治疗中,本研究的DOXHAuNS-TSL结合NIR激光照射介导的联合效应具备重要的参考价值和方向性意义。在光敏脂质体基础上,引入Her2抗体,通过化学修饰对其进行表面修饰与嫁接,制备Her2免疫光敏脂质体,可以特异性地被BT474及SKOV3所摄取。在BT474/A549或SKOV3/A549细胞共孵育体系中,DOXHAuNS-Her2-TSL能够特异性地主动靶向至BT474或者SKOV3细胞；并且导致SKOV3/A549体系中,SKOV3的相对存活率从47.4%下降至22.4%；BT474/A549体系中,BT474的相对存活率从从54.3%降至29.1%。在荷SKOV3/A549双肿模型动物体内分布研究中,DOXHAuNS-TSL更多地靶向至SKOV3实体瘤。在抗肿瘤药效学研究中,我们数据表明,照射NIR条件下,较之DOXHAuNS-TSL组,DOXHAuNS-Her2-TSL组展现更为优良的抗肿瘤效果。主要是它能够主动靶向至肿瘤部位,进一步扩大了光敏脂质体的光热和化学治疗联合抗肿瘤的效应。
[Abstract]:Liposome is one of the best drug carrier types in the field of drug delivery however, control wrapped drugs in specific space and time of release from liposomes is still a problem to be solved urgently. Photothermal ablation (PTA) is a kind of using near infrared (NIR) laser heat to kill tumor cells the technology; technology shows a good prospect of clinical application in tumor therapy. However, only by PTA treatment is difficult to completely cure the tumor, because due to the uneven part of the tumor killing agent the amount of heat than the heat distribution of the heat. In this study, we prepared a novel thermosensitive lipid body the preparation, also known as photosensitive liposomes. The drug loaded liposomes containing hollow gold nanoparticles (hollow gold nanospheres, HAuNS) and adriamycin (doxorubicin, DOX).
The hollow gold nanoparticles (hollow gold nanospheres, HAuNS), the particle size is 35.6 + 1.7nm, the polydispersity index PI 0.003. near infrared with surface plasmon resonance (surface plasmon resonance) good optical properties, can absorb near-infrared light and generate heat. Transmission electron microscopy results have been verified by hydrophobic modified HAuNS that can adhere to the lipid membrane. In the thermal NIR laser irradiation conditions, photosensitive liposomes showed photothermal effect, can control drug release. Our experimental results show that the NIR laser irradiation, DOX from photosensitive liposomes (DOXHAuNS-TSL) in rapid and sustained release. In the study of in vitro release NIR, under the irradiation of 24h, the cumulative release amount of DOX from DOXHAuNS-TSL increased by nearly 40%; without NIR irradiation, 24h, cumulative release amount of DOX from DOXHAuNS-TSL is not more than 6%. is mainly due to sparse The water induced HAuNS adheres to the lipid membrane and absorbs heat to produce heat. The elevated temperature reaches the phase transition temperature of the liposome and thus improves the permeability of the lipid membrane.
Our data also showed that, compared with single DOXHAuNS-TSL, single DOX-TSL, HAuNS-TSL or NIR combined with laser irradiation; using DOXHAuNS-TSL combined with NIR laser irradiation, showing a more significant cytotoxicity. Mainly from the following three aspects: 1) caused by photothermal ablation (PTA) effect, 2) DOX DOXHAuNS-TSL in the lead from the trigger increase the intracellular drug concentration, 3) the combined effect of photothermal effect and DOX drug effects. Moreover, the anti-tumor in vivo study showed that the combined effects of treatment by DOXHAuNS-TSL combined with NIR laser irradiation mediated by thermal and chemical, than by HAuNS-TSL combined with NIR laser irradiation mediated photothermal ablation (PTA) effect, show more completely significant anti-tumor effect. PTA revealed in the clinical application of treatment of cancer, this study combined effect of DOXHAuNS-TSL combined with NIR laser irradiation mediated has important reference value and direction of Italy Righteousness.
In the photosensitive liposomes on the basis of the introduction of Her2 antibody by chemical modification of surface modification and grafting on the preparation of Her2 immune photosensitive liposomes can specifically by BT474 and SKOV3. The uptake in BT474/A549 or SKOV3/A549 cells were incubated in the system, DOXHAuNS-Her2-TSL can be specifically targeting to BT474 or SKOV3 cells; and lead to the SKOV3/A549 system, the relative survival rate decreased from 47.4% to 22.4% SKOV3; the BT474/A549 system, the relative survival rate from 54.3% fell to 29.1%. in SKOV3/A549 bearing double swollen distribution in vivo animal model research in BT474, DOXHAuNS-TSL is more targeted to SKOV3 solid tumor.
The anti tumor effect of our data show that NIR irradiation conditions, compared to DOXHAuNS-TSL group, DOXHAuNS-Her2-TSL group showed more excellent antitumor effect. It is mainly to active targeting to the tumor site, to further expand the effect of thermal and chemical treatment of photosensitive liposomes combined with anti tumor.

【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R943

【共引文献】