Single-cell real-time imaging of transgene expression upon lipofection

Area of Science:

• Cell Biology
• Molecular Biology
• Biotechnology

Background:

• Lipofection is a key method for introducing nucleic acids into cells.
• Understanding transfection reagent efficiency and mechanisms is crucial for gene delivery applications.

Purpose of the Study:

• To quantitatively compare the performance of Lipofectamine and DC-Chol/DOPE transfection reagents.
• To investigate the real-time, single-cell dynamics of reporter gene expression following lipofection.
• To elucidate the mechanism underlying protein expression symmetry in daughter cells post-transfection.

Main Methods:

• Real-time confocal imaging of live cells expressing a genetically-encoded fluorescent reporter.
• Quantification of single-cell fluorescence intensity.
• Measurement of fluorescence over time in daughter cell pairs.
• Development of a mathematical model to explain expression symmetry.

Main Results:

• Detectable fluorescent reporter protein expression was observed only in dividing cells for both transfection methods.
• Lipofectamine demonstrated significantly higher symmetry in protein expression between daughter cells compared to DC-Chol/DOPE.
• A model correlating expression symmetry with bioavailable DNA copies before nuclear breakdown was proposed.

Conclusions:

• Cell division is essential for detectable reporter protein expression after lipofection.
• Lipofectamine offers superior control over protein expression symmetry between daughter cells.
• This study establishes a quantitative platform for evaluating and understanding lipofection reagents.