Department of Pharmaceutical Sciences, Massachusetts College of Pharmacy and Health Sciences, Boston, MA 02115, USA.
Osteoarthritis Cartilage. 2013 Feb;21(2):377-84. doi: 10.1016/j.joca.2012.11.011. Epub 2012 Nov 24.
To evaluate cartilage diffusion and isolated chondrocyte association of micelles and liposomes and to determine the effect of cell-penetrating peptide (CPP) surface functionalization and extracellular matrix depletion on chondrocyte association and cartilage diffusion, respectively.
Rhodamine-labeled micelles and liposomes were incubated with bovine chondrocytes and cell-associated fluorescence was quantified using flow cytometry. Rhodamine-labeled CPP-modified micelles and liposomes were incubated with chondrocytes and cell-associated fluorescence was compared to unmodified nanocarriers. Rhodamine-labeled micelles and liposomes were incubated with bovine cartilage explants for 1, 2 and 4 h and cartilage-associated fluorescence was compared across groups. Cartilage explants were treated with interleukin-1 alpha (IL-1α) or with 0.25% trypsin. Rhodamine-labeled micelles and liposomes were incubated with control, IL-1 and trypsin-treated explants and cartilage-associated fluorescence was compared across groups.
Chondrocyte-associated fluorescence following treatment with micelles was significantly higher (P < 0.001) than fluorescence in the cells treated with liposomes while there was no difference between cell-associated fluorescence in the liposomes-treated and untreated controls. CPP-modified nanocarriers exhibited a significant increase in chondrocyte association compared to unmodified nanocarriers (P < 0.001). Micelles exhibited a time and concentration-dependent diffusion in cartilage explants while liposomes showed no diffusion. Following IL-1 and trypsin treatments, micelle diffusion in articular cartilage was significantly higher (P < 0.001) than their diffusion in untreated explants.
Micelles exhibit superior association with isolated chondrocytes compared to liposomes. Surface modification with a CPP enhances chondrocyte association of both nanocarriers. 15 nm diameter micelles are better than 138 nm diameter liposomes in penetrating articular cartilage and extracellular matrix depletion enhances micelle penetration.
评估胶束和脂质体的软骨扩散和分离软骨细胞的关联，并确定细胞穿透肽（CPP）表面功能化和细胞外基质耗竭对软骨细胞关联和软骨扩散的影响。
用罗丹明标记的胶束和脂质体孵育牛软骨细胞，并使用流式细胞术定量细胞相关荧光。用 CPP 修饰的罗丹明标记的胶束和脂质体孵育软骨细胞，并将细胞相关荧光与未修饰的纳米载体进行比较。用罗丹明标记的胶束和脂质体孵育牛软骨外植体 1、2 和 4 h，并比较各组的软骨相关荧光。用白细胞介素 1 阿尔法（IL-1α）或 0.25%胰蛋白酶处理软骨外植体。用对照、IL-1 和胰蛋白酶处理的外植体孵育罗丹明标记的胶束和脂质体，并比较各组的软骨相关荧光。
用胶束处理后，软骨细胞的细胞相关荧光明显高于（P < 0.001）用脂质体处理的细胞中的荧光，而脂质体处理的细胞与未处理的对照细胞之间的细胞相关荧光没有差异。与未修饰的纳米载体相比，CPP 修饰的纳米载体与软骨细胞的关联显著增加（P < 0.001）。胶束在软骨外植体中表现出时间和浓度依赖性的扩散，而脂质体则没有扩散。在 IL-1 和胰蛋白酶处理后，胶束在关节软骨中的扩散明显高于（P < 0.001）未经处理的外植体中的扩散。
胶束与分离的软骨细胞的关联优于脂质体。CPP 的表面修饰增强了两种纳米载体的软骨细胞关联。15nm 直径的胶束比 138nm 直径的脂质体更能穿透关节软骨和细胞外基质耗竭增强胶束穿透。
