Monitoring induced gene expression of single cells in a multilayer microchip

Area of Science:

• Biotechnology
• Cell Biology
• Microfluidics

Background:

• Single cell analysis is crucial for understanding cellular heterogeneity.
• Conventional methods struggle with precise, long-term stimulation and individual cell tracking.
• Developing advanced microfluidic platforms is essential for detailed cellular studies.

Purpose of the Study:

• To present a novel two-layer microfluidic system for long-term single cell measurements.
• To enable precise control over the concentration and timing of external stimuli delivery.
• To investigate heterogeneous single cell responses to inducible gene expression.

Main Methods:

• Utilized a two-layer microfluidic device with separate layers for cell culture and chemical delivery.
• Employed a porous polyester membrane for controlled compound transport and diffusion.
• Demonstrated the system using human embryonic kidney cells (HEK293) with an inducible gene expression system (ZsGreen1-DR).

Main Results:

• Successfully monitored single cell responses to varying tetracycline concentrations and exposure times.
• Observed heterogeneous expression patterns of the fluorescent protein ZsGreen1-DR among individual cells.
• Analyzed both individual cell responses and average responses of multiple cells in parallel.

Conclusions:

• The microfluidic platform facilitates systematic, long-term studies of single cell behavior under defined conditions.
• Provides insights into cellular mechanisms and kinetics not achievable with traditional methods.
• Represents a valuable tool for advancing single cell research and understanding cellular responses.