A microfluidic-based system for analysis of single cells based on Ca2+ flux

Area of Science:

• Biotechnology
• Cell Biology
• Microfluidics

Background:

• Calcium flux is a critical cellular signaling pathway.
• Monitoring cellular responses to agonists is vital for drug discovery.
• Existing methods for calcium flux monitoring can be time-consuming and complex.

Purpose of the Study:

• To develop a microfluidic system for in situ monitoring of calcium flux in Chinese hamster ovary (CHO) cells.
• To enable real-time assessment of cellular responses to various agonists.
• To provide a high-throughput and sensitive platform for pharmacological screening.

Main Methods:

• A microfluidic chip was fabricated with a functionalized glass channel surface using 3-aminopropyltriethoxysilane (APTS) for cell immobilization.
• Chinese hamster ovary (CHO) cells were cultured and loaded with the calcium-sensitive indicator Fluo-4 AM.
• Agonists were introduced into the microfluidic channel in a sequential plug-flow manner to elicit calcium flux.
• Fluorescent intensity, indicative of intracellular calcium levels, was measured in real-time using a fluorescence microscope.

Main Results:

• The microfluidic system successfully monitored calcium flux in CHO cells in response to different agonists.
• Dose-dependent responses were observed for various agonists, demonstrating the system's quantitative capabilities.
• The functionalized channel surface effectively immobilized CHO cells, ensuring stable measurements.
• Continuous flow and plug-based reagent delivery facilitated rapid and sequential stimulation.

Conclusions:

• The developed microfluidic system offers a robust and efficient platform for in situ monitoring of calcium flux.
• This technology has significant potential for high-throughput screening of drug candidates and toxicological assessments.
• The system provides a valuable tool for studying cellular signaling pathways in a controlled microenvironment.