Integrin-Targeted Cyclic Forces Accelerate Neural Tube-Like Rosette Formation from Human Embryonic Stem Cells

Area of Science:

• Mechanobiology
• Stem Cell Differentiation
• Developmental Neuroscience

Background:

• Mechanical forces are crucial regulators of human embryonic stem cell (hESC) differentiation.
• Understanding how dynamic forces influence neural induction is essential for regenerative medicine and developmental studies.

Purpose of the Study:

• To investigate the impact of dynamic mechanical forces on the neural induction of hESCs.
• To explore the synergistic effects of mechanical stimulation and chemical cues in neural differentiation.

Main Methods:

• Utilized acoustic tweezing cytometry (ATC) to apply cyclic mechanical forces/strains to hESCs via ultrasound-actuated microbubbles.
• Cultured hESCs with and without ATC treatment in neural induction medium (NIM).
• Assessed neural induction by monitoring neuroectoderm markers (Pax6, Sox1) and neural rosette formation.
• Investigated the role of signaling pathways (FAK, myosin, RhoA/ROCK) in mediating ATC effects.

Main Results:

• Combined ATC and NIM treatment accelerated neural induction, upregulating Pax6 and Sox1 markers within 6 hours and inducing neural tube-like rosettes by 48 hours.
• ATC alone decreased Oct4 expression but did not promote neural differentiation markers or rosette formation without NIM.
• ATC-induced effects were dependent on integrin signaling, FAK, myosin activity, and RhoA/ROCK pathway activation.

Conclusions:

• Acoustic tweezing cytometry (ATC) synergizes with neural induction medium (NIM) to accelerate hESC neural induction.
• This study reveals an integrated mechanobiology mechanism requiring both physical forces and chemical signals for efficient neural differentiation.
• The findings highlight the potential of combining mechanical stimulation with biochemical cues for controlled stem cell fate determination.