叶酸受体在血液肿瘤细胞株的表达及叶酸-聚乙烯亚胺共聚物的制备

目的:研究叶酸受体(folate receptor,FR)在血液肿瘤细胞表达的特点,合成叶酸-聚乙烯亚胺(FA-PEI)聚合物,探讨其作为靶向性基因输送载体的可行性.方法:用实时荧光定量PCR(real time PCR)法检测α、β、γ3种FR在血液肿瘤细胞K562、K562/A02、U266细胞株上的表达;利用叶酸(FA)活性酯在微碱性条件下与聚乙烯亚胺(polyethylenimine,PEI)的支链氨基反应,合成FA-PEI共聚物;用葡聚糖凝胶柱G-25分离、纯化;用紫外分光光度计波长扫描法及氢核磁共振谱(~1H NMR)法验证交联是否成功.结果:α、β、γ3种FR在K562、K562/A02、U266 3种细胞株上均表达,其中,α-FR的表达占优势,较β-FR和γ-FR表达量高;紫外分光光度计扫描图谱在365 nm处出现叶酸的特征性吸收峰;核磁共振(~1H NMR)示:在2.5～3.2处出现PEI亚甲基质子的特征性化学位移,在6.5～9.0处出现叶酸芳香质子的特征性氢信号.结论:FR在K562、K562/A02、U266 3种细胞株上均有较高表达;FA-PEI偶联成功,为其作为血液肿瘤治疗中1种潜在的靶向性基因输送载体提供了依据.

Expressions of folate receptor in hematology malignant cell lines and synthesis of folate-polyethylenimine

Aim: Examining the expression patterns folate receptor in hematology malignant cell lines and synthesis a new potential targeted gene carrier vector folate-polyethylenimine. Methods: ①Real-time fluorescence quantitative PCR was used to detect the expression patterns of folate receptor in three kinds of hematology tumor cell lines. ② The activated folate (N-hydroxysuccinimide ester of folic acid) was conjuated to the surface of PEI via the branched amino groups. Then the FA-PEI copolymer was purified with Sephadex G-25 column and completely separated from unreacted folate. Folate-polyethylenimine was determined by ultraviolet (UV) spectrophotometric analysis and hydrogen nuclear magnetic resonance spectroscopy (~1H NMR). Results: ①Three patterns of folate receptor α、β、γ were expressed in hematology tumor cell lines K562, K562/A02, U266 and the expression levels of α-FR was significantly higher than those ofβ-FR and γ-FR. Thus the expression of α-FR was dominant. ② Ultraviolet (UV) spectro-photometric analysis found that the isolated sample displays the characteristic absorption peak of folate in 365 nm. ③~1HNMR test showed that the characteristic chemical shifts of methylene proton was in 2.5～3.2 and the characteristic aromatic hydrogen proton signal of folic acid was in 6.5～9.0. Conclusions:① the expression levels ofα-FR was higher than those ofβ-FR andγ-FR in the three hematology tumor cell lines.②The successful coupling of FA-PEI can be used as a potential targeted gene dehvery vector and providing evidence in the treatment of hematology tumor.