文献：NanoparticleLoaded PolarizedMacrophages for Enhanced Tumor Targeting and CellChemotherapy

文献链接：https://read.cnki.net/web/Journal/Article/NANO202101006.html

作者：Teng Hou, Tianqi Wang, Weiwei Mu, Rui Yang, Shuang Liang, Zipeng Zhang, Shunli Fu, Tong Gao, Yongjun Liu, Na Zhang

相关产品：DSPE-rhodamine B 磷脂-罗丹明B

原文摘要：Cell therapy is a promising strategy for cancer therapy. However, its therapeutic efciency remains limited due to the complex and immunosuppressive nature of tumor microenvironments. In this study, the “cell-chemotherapy” strategy was presented to enhance antitumor efcacy. M1-type macrophages, which are therapeutic immune cells with both of immunotherapeutic ability and targeting ability, carried sorafenib (SF)-loaded lipid nanoparticles (M1/SLNPs) were developed. M1-type macrophages were used both as therapeutic tool to provide immunotherapy and as delivery vessel to target deliver SF to tumor tissues for chemotherapy simultaneously. M1-type macrophages were obtained by polarizing macrophages using lipopolysaccharide, and M1/ SLNPs were obtained by incubating M1-type macrophages with SLNP. Tumor accumulation of M1/SLNP was increased compared with SLNP (p <0.01), which proved M1/SLNP could enhance tumor targeting of SF. An increased ratio of M1-type macrophages to M2-type macrophages, and the CD3+CD4+ T cells and CD3+CD8+ T cell quantities in tumor tissues after treatment with M1/SLNP indicated M1/SLNP could relieve the immunosuppressive tumor microenvironments. The tumor volumes in the M1/SLNP group were signifcantly smaller than those in the SLNP group (p<0.01), indicating M1/SLNP exhibited enhanced antitumor efcacy. Consequently, M1/SLNP showed great potential as a novel cell chemotherapeutic strategy combining both cell therapy and targeting chemotherapy.

DSPE-rhodamine B是由DSPE、rhodamine B组成，通常为红色粉末。DSPE具有疏水性脂尾和亲水性头基，rhodamine B是一种红色荧光染料，二者偶联后，既保留了DSPE的脂质特性，又具备了荧光标记能力.rhodamine B可发出红色荧光，其激发波长一般在540-560nm，发射波长在570-600nm左右，荧光量子产率高、光稳定性好.在生物成像中，可标记细胞、组织或生物分子，用于观察其在体内的分布和动态变化；在化合物递送方面，可作为化合物载体的组成部分，追踪化合物在体内的分布和释放；还可用于细胞追踪与可视化、蛋白质分析等研究。该文献研究中提出了m1型巨噬细胞是一种具有靶向能力的免疫细胞，携带索拉非尼（SF）负载的脂质纳米颗粒（M1/SLNPs）。

图：M1/SLNP的制备。

SLNP的准备

采用纳米共沉淀法制备了SLNPs。SF溶于甲醇中。大豆卵磷脂溶解在Tween-80水溶液中。使用微注射泵不断机械搅拌，将有机相添加到Tween-80水溶液中。经甲醇蒸发后得到SLNPs。通过单因素研究确定了最佳配方。研究了SF/大豆卵磷脂质量比和大豆卵磷脂浓度。在制备C6-LNP和Cy5.5-LNP时，将SF替换为C6和Cy5.5−1。其他程序与SLNP相似。

采用CLSM和TEM评价SLNP在M/SLNP或M1/SLNP中的稳定性

简单地说，将DSPE-罗丹明B和大豆卵磷脂溶解在Tween-80水溶液中中，其他方法与C6-LNP相似。因此，我们获得了C6-LNP，其中用罗丹明b快速标记LNP，巨噬细胞在12孔板中培养过夜。将巨噬细胞与LPS孵育，获得m1型巨噬细胞。加入C6-LNPs，与巨噬细胞或m1型巨噬细胞孵育。PBS洗涤后，细胞与添加胎牛血清的新鲜DMEM培养基中孵育不同的时间（0、4、8、12和24 h）。在预定的时间点，用PBS洗涤细胞，并在CLSM下观察。并在24 h后获得细胞，并在透射电镜下观察。

图：M1/SLNP用于增强HCC的示意图

结论：用脂多糖极化巨噬细胞获得M1型巨噬细胞，用M1型巨噬细胞与DSPE-RB标记的SLNP孵育获得M1/ SLNPs。与SLNP相比，M1/SLNP的tumor积累增加（p <0.01），证明M1/SLNP可以增强SF的tumor靶向性。M1/SLNP后，tumor组织中M1型巨噬细胞与M2型巨噬细胞的比例增加，CD3+CD4+ T细胞和CD3+CD8+ T细胞的数量增加，表明M1/SLNP可以缓解免疫抑制tumor微环境。