A microfluidic system for long-term time-lapse microscopy studies of mycobacteria

Area of Science:

• Microbiology
• Cell Biology
• Biotechnology

Background:

• Bacterial phenotypic heterogeneity drives crucial phenomena like persistence, a key factor in diseases such as tuberculosis.
• Studying non-genetic phenotypic variations in individual bacterial cells is challenging due to their transient nature and the need for real-time observation.
• Mycobacterial growth in three dimensions poses specific challenges for microfluidic system development.

Purpose of the Study:

• To develop and validate a novel microfluidic device for observing single mycobacterial cell behavior.
• To enable real-time monitoring of mycobacterial growth and antibiotic-induced cell death.
• To facilitate the study of bacterial persistence and cell genealogy in mycobacteria.

Main Methods:

• Construction of a microfluidic device designed for mycobacterial single-cell analysis.
• Utilizing a hydrogel matrix within the device to promote planar growth of Mycobacterium smegmatis.
• Employing confocal laser scanning microscopy and propidium iodide staining for real-time monitoring of cell growth and death.

Main Results:

• Demonstrated successful real-time analysis and long-term culture of individual Mycobacterium smegmatis cells.
• Observed cell growth and death dynamics under antibiotic treatment within the microfluidic device.
• Validated the device's capability to study cell genealogy and identify rare persistent states.

Conclusions:

• The novel microfluidic device enables unprecedented real-time observation of single mycobacterial cells.
• This technology is crucial for investigating the mechanisms of bacterial persistence and antibiotic survival.
• The device offers a powerful platform for understanding mycobacterial population heterogeneity and developing new therapeutic strategies.