Liu Ching-Wen, Chang Li-Ching, Lin Kai-Jen, Yu Tsan-Jung, Tsai Ching-Chung, Wang Hao-Kuang, Tsai Tong-Rong
School of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
Department of Occupational Therapy, I-Shou University, Kaohsiung 824, Taiwan ; Department of Pharmacy, E-DA Hospital, I-Shou University, Kaohsiung 824, Taiwan.
Biomed Res Int. 2014;2014:473823. doi: 10.1155/2014/473823. Epub 2014 Dec 15.
This study aimed to develop optimal gelatin-based mucoadhesive nanocomposites as scaffolds for intravesical gene delivery to the urothelium. Hydrogels were prepared by chemically crosslinking gelatin A or B with glutaraldehyde. Physicochemical and delivery properties including hydration ratio, viscosity, size, yield, thermosensitivity, and enzymatic degradation were studied, and scanning electron microscopy (SEM) was carried out. The optimal hydrogels (H), composed of 15% gelatin A175, displayed an 81.5% yield rate, 87.1% hydration ratio, 42.9 Pa·s viscosity, and 125.8 nm particle size. The crosslinking density of the hydrogels was determined by performing pronase degradation and ninhydrin assays. In vitro lentivirus (LV) release studies involving p24 capsid protein analysis in 293T cells revealed that hydrogels containing lentivirus (H-LV) had a higher cumulative release than that observed for LV alone (3.7-, 2.3-, and 2.3-fold at days 1, 3, and 5, resp.). Lentivirus from lentivector constructed green fluorescent protein (GFP) was then entrapped in hydrogels (H-LV-GFP). H-LV-GFP showed enhanced gene delivery in AY-27 cells in vitro and to rat urothelium by intravesical instillation in vivo. Cystometrogram showed mucoadhesive H-LV reduced peak micturition and threshold pressure and increased bladder compliance. In this study, we successfully developed first optimal gelatin-based mucoadhesive nanocomposites as intravesical gene delivery scaffolds.
本研究旨在开发基于明胶的最佳黏膜黏附性纳米复合材料，作为向尿路上皮进行膀胱内基因递送的支架。通过将明胶A或B与戊二醛化学交联来制备水凝胶。研究了包括水合率、粘度、尺寸、产率、热敏感性和酶降解在内的物理化学和递送特性，并进行了扫描电子显微镜（SEM）观察。由15%明胶A175组成的最佳水凝胶（H）显示出81.5%的产率、87.1%的水合率、42.9 Pa·s的粘度和125.8 nm的粒径。通过进行链霉蛋白酶降解和茚三酮测定来确定水凝胶的交联密度。涉及对293T细胞中p24衣壳蛋白分析的体外慢病毒（LV）释放研究表明，含有慢病毒的水凝胶（H-LV）的累积释放量高于单独的LV（在第1、3和5天分别为3.7倍、2.3倍和2.3倍）。然后将来自构建绿色荧光蛋白（GFP）的慢病毒载体的慢病毒包裹在水凝胶中（H-LV-GFP）。H-LV-GFP在体外AY-27细胞中以及通过体内膀胱内滴注对大鼠尿路上皮均显示出增强的基因递送。膀胱压力容积测定显示，黏膜黏附性H-LV降低了排尿峰值和阈值压力，并增加了膀胱顺应性。在本研究中，我们成功开发了首个基于明胶的最佳黏膜黏附性纳米复合材料作为膀胱内基因递送支架。
