Orthogonal alignment of multilayered MC3T3-E1 cells induced by cyclic stretch

Area of Science:

• Cell biology
• Biomechanics
• Tissue engineering

Background:

• Cellular response to mechanical stimuli is crucial in tissue development and disease.
• Monolayer cell alignment under cyclic stretch is well-documented.
• The behavior of multilayer cells under mechanical stress is less understood.

Purpose of the Study:

• Investigate the alignment behavior of multilayer MC3T3-E1 osteoblast-like cells under cyclic stretch.
• Determine the role of transmitted strain and intracellular tension in multilayer cell alignment.

Main Methods:

• Culturing MC3T3-E1 cells to form multilayer structures.
• Applying 10% cyclic stretch at 1 Hz to the cell cultures.
• Measuring transmitted strain to different cell layers.
• Modulating intracellular tension using Y-27632 and calyculin A.

Main Results:

• Lower cell layers aligned with stretch direction after 12 hours.
• Upper cell layers aligned perpendicular to stretch direction after 24 hours.
• Transmitted strain to upper layers increased over time, correlating with alignment changes.
• Pharmacological inhibition of intracellular tension promoted alignment in the stretch direction for both layers.
• Increased intracellular tension abolished significant cell alignment.

Conclusions:

• Multilayer cell alignment under cyclic stretch is layer-dependent and influenced by mechanical signal transmission.
• Intracellular tension plays a critical role in regulating cell alignment direction.
• Lower layer cell alignment may result from reduced intracellular tension during cyclic stretching.