Leukocyte transmigration and longitudinal forward-thrusting force in a microfluidic Transwell device

Area of Science:

• Immunology
• Cell Biology
• Biophysics

Background:

• Leukocyte transmigration is vital for immune response.
• Traditional Transwell assays limit in situ imaging, hindering analysis of migration dynamics.
• Understanding cell migration mechanics is crucial for immune cell function.

Purpose of the Study:

• To investigate T lymphocyte migration from 2D to 3D using microfluidic Transwells.
• To measure forces involved in cell transmigration and 3D migration.
• To analyze the roles of adhesion, contractility, and external pressure in cell migration.

Main Methods:

• Utilized microfluidic Transwells for imaging 2D to 3D cell transition.
• Measured longitudinal forward-thrusting force of T lymphocytes.
• Imposed pressure drops across microchannels to assess stalling conditions.

Main Results:

• T lymphocytes showed propensity to transmigrate without chemotaxis, with adhesion and contractility crucial for nucleus penetration.
• 3D migration in smooth channels relied on cell envelope propulsion, independent of topography.
• Cellular adhesion and pressure controlled stalling, with LFA-1 mediated adhesion increasing stall force.

Conclusions:

• Microfluidic Transwells offer a powerful tool to study cell migration, including 2D/3D movement, barotaxis, and chemotaxis.
• Cellular adhesion and pressure dynamics significantly influence 3D migration and stalling.
• Findings provide insights into the mechanical regulation of immune cell movement.