摘要
目的探讨多价阳离子脂质体介导的pCKM-mPTH质粒治疗甲状旁腺功能低下症(HPT)的最佳方案。方法用DNaseⅠ敏感性试验测定脂质体对质粒的保护作用,用不同比例的脂质复合物及裸质粒进行体内外转染,收集细胞培养液和血清,采用放射免疫法测定其甲状旁腺激素(PTH)含量。结果脂质复合物比例为2∶1时,即对DNA有明显的保护作用;在体外转染实验中,复合物比例在3∶1时PTH表达量最高,为每24小时(16.4±4.8)pg/10 000细胞,而在此比例下pCKM-mPTH质粒达20μg/100μl时,模型体内PTH的血清浓度最高,为35.9 pg/m l±2.2 pg/m l。结论与裸质粒相比,多价阳离子脂质体更适宜于作为HPT基因治疗的非病毒载体,而其介导重组质粒pCKM-mPTH直接转染肌肉的良好效能取决于脂质复合物的构成比例和剂量。
Objective To investigate the optimal ratio of polycationic liposome mediated pCKM- mPTH recombinant gene transfer to skeleton cells in the genetherapy of hypoparathyroidism（HPT）. Methods The protective roles of polycationic liposome to DNA were observed by the DNase Ⅰ sensitive test. Liposomeplasmid complex （lipoplexes） with various liposome to plasmid ratio and the naked plasmid were transferred both in vivo and in vitro. The supematants and serums were collected for measuring parathyroid hormone （PTH） with radioimmunoassay. Results When the ratio of lipoplexes reached 2： 1, there were obviously protective roles to DNA. While it was 3： 1, mPTH transgene expressing reached peak which the PTH amount was（ 16. 4 ±4. 8） pg/10 000 cells/24 h. Furthermore, the amount serum PTH of the HPT model SD rats reached the highest （35. 9 pg/ml ± 2. 2 pg/ml ） till the concentration of pCKM-mPTH is 20 μg/100 μl with 3：1 ratio of lipoplexes. Condusion Polycationic liposomes are more effective than naked plasmids for pCKM-mPTH recombinant gene transfer to skeleton cells. The results also indicated that the effect of pCKM-mPTH transferring into muscles might be depended on the optimal ratio and dosage of lipoplexes.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2006年第12期837-840,共4页
National Medical Journal of China
基金
国家自然科学基金资助项目(39970726)
