Intracellular uptake and intracavitary targeting of folate-conjugated liposomes in a mouse lymphoma model with up-regulated folate receptors
Intracellular uptake and intracavitary targeting of folate-conjugated liposomes in a mouse lymphoma model with up-regulated folate receptors
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DOI：
10.1158/1535-7163.mct-05-0543
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发表时间：
2006-04-01
影响因子：
5.7
通讯作者：
Gabizon, A
中科院分区：
文献类型：
--
作者：
Shmeeda, H;Mak, L;Gabizon, A
叶酸受体在广泛的恶性肿瘤中过表达，是选择性递送抗癌剂至表达叶酸受体的肿瘤的有吸引力的靶点。本研究探讨叶酸-脂质缀合物作为一种手段，提高肿瘤的选择性脂质体封装的药物在小鼠淋巴瘤模型。将叶酸衍生的聚乙二醇（PEG（3350））二硬脂酰-磷脂酰乙醇胺以各种浓度后加载到以下制剂中：放射性标记的聚乙二醇化脂质体、在水性室中用葡聚糖荧光素标记的聚乙二醇化脂质体和聚乙二醇化脂质体多柔比星（PLD，Doxil）。我们将叶酸靶向的放射性标记或荧光脂质体与叶酸受体上调的小鼠J6456淋巴瘤细胞（J6456-FR）一起孵育，以确定脂质体细胞缔合所需的脂质双层中的最佳配体浓度，并检查叶酸靶向脂质体是否被悬浮液中的J6456-FR细胞内化。基于放射性和荧光激活细胞分选分析定量脂质体与细胞的结合，并通过共聚焦荧光显微镜评估内化。我们发现使用我们的配体的最佳配体摩尔浓度为0.5%。与非靶向脂质体相比，在叶酸靶向脂质体中发现细胞相关荧光的大量脂质剂量依赖性增加。共聚焦深度扫描显示大量的叶酸靶向脂质体被J6456-FR细胞内化。在携带腹水J6456-FR肿瘤的小鼠中腹膜内注射叶酸靶向PLD后，也在体内观察到J6456-FR细胞对叶酸靶向PLD的结合和摄取。在腹腔注射模型中，当叶酸靶向PLD与非靶向PLD相比时，腹水肿瘤细胞中的药物水平增加了17倍，而血浆中的药物水平降低了14倍。叶酸靶向脂质体代表了一种有吸引力的方法，用于将药物细胞内递送至表达叶酸受体的淋巴瘤细胞，并且似乎是体内腔内药物靶向的有前途的工具。
The folate receptor is overexpressed in a broad spectrum of malignant tumors and represents an attractive target for selective delivery of anticancer agents to folate receptor-expressing tumors. This study examines folate-lipid conjugates as a means of enhancing the tumor selectivity of liposome-encapsulated drugs in a mouse lymphoma model. Folate-derivatized polyethylene glycol (PEG(3350))distearoyl-phosphatidylethanolamine was post-loaded at various concentrations into the following preparations: radiolabeled PEGylated liposomes, PEGylated liposomes labeled in the aqueous compartment with dextran fluorescein, and PEGylated liposomal doxorubicin (PLD, Doxil). We incubated folate-targeted radiolabeled or fluorescent liposomes with mouse J6456 lymphoma cells up-regulated for their folate receptors (J6456-FR) to determine the optimal ligand concentration required in the lipid bilayer for liposomal cell association, and to examine whether folate-targeted liposomes are internalized by J6456-FR cells in suspension. Liposomal association with cells was quantified based on radioactivity and fluorescence-activated cell sorting analysis, and internalization was assessed by confocal fluorescence microscopy. We found an optimal ligand molar concentration of similar to 0.5% using our ligand. A substantial lipid dose-dependent increase in cell-associated fluorescence was found in folate-targeted liposomes compared with nontargeted liposomes. Confocal depth scanning showed that a substantial amount of the folate-targeted liposomes are internalized by J6456-FR cells. Binding and uptake of folate-targeted PLD by J6456-FR cells were also observed in vivo after i.p. injection of folate-targeted PLD in mice bearing ascitic J6456-FR tumors. The drug levels in ascitic tumor cells were increased by 17-fold, whereas those in plasma were decreased by 14-fold when folate-targeted PLD were compared with nontargeted PLD in the i.p. model. Folate-targeted liposomes represent an attractive approach for the intracellular delivery of drugs to folate receptor-expressing lymphoma cells and seem to be a promising tool for in vivo intracavitary drug targeting.