Objectives

Heat treatment as a physical method could increase the cellular uptake of nucleic acids. In this study, the effects of heat shock were evaluated to enhance the transfection efficiency of three plasmid DNAs into HeLa and TC-1 cancerous, and HEK-293 T and Vero non-cancerous cell lines using lipofectamine 2000 reagent.

Methods

Two methods of cell- and DNA-based heat treatment were used. Heating DNA solution was performed at 94 °C for 5, 10 and 15 min, and also 72 °C for 30, 60 and 120 min, individually. Moreover, heating the cells was done by incubation at 42 °C for 2 h in different times such as before, during and after DNA transfection.

Results

Our data showed that the conformation of plasmid DNAs was changed at different temperatures with increasing time. The heat-treated plasmid DNAs (94 °C for 10 min or 72 °C for 30 min) indicated higher transfection efficiency than untreated plasmid DNAs (p < 0.05). Furthermore, heat treatment of cells before and during the transfection was higher than untreated cells (p < 0.01). Our results demonstrated that DNA transfection efficiency in cancerous cells was less than non-cancerous cells (p < 0.01).

Conclusion

Generally, these findings showed that transfection mediated by thermal stimulation could enhance gene transfection in mammalian cell lines.

中文翻译：

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哪一种热方法（加热 DNA 或细胞）可增强哺乳动物细胞中的基因表达？

目标

热处理作为一种物理方法可以增加细胞对核酸的吸收。在本研究中，使用 lipofectamine 2000 试剂评估了热激对提高三种质粒 DNA 转染 HeLa 和 TC-1 癌细胞系以及 HEK-293 T 和 Vero 非癌细胞系的效率的效果。

方法

使用了两种基于细胞和基于 DNA 的热处理方法。分别在 94 °C 下加热 DNA 溶液 5、10 和 15 分钟，以及在 72 °C 下分别加热 30、60 和 120 分钟。此外，通过在 DNA 转染之前、期间和之后的不同时间在 42°C 下孵育 2 小时来加热细胞。

结果

我们的数据表明，随着时间的增加，质粒DNA的构象在不同温度下发生变化。热处理的质粒 DNA（94 °C 10 分钟或 72 °C 30 分钟）表明转染效率高于未处理的质粒 DNA（p  < 0.05）。此外，转染前和转染过程中细胞的热处理高于未处理的细胞（p  < 0.01）。我们的结果表明，癌细胞中的 DNA 转染效率低于非癌细胞 ( p  < 0.01)。

结论

一般来说，这些发现表明热刺激介导的转染可以增强哺乳动物细胞系中的基因转染。