π-SACS: pH Induced Self-Assembled Cell Sheets Without the Need for Modified Surfaces.

Area of Science:

• Tissue Engineering and Regenerative Medicine
• Biomaterials Science
• Cell Biology

Background:

• High cell density and cell-cell/cell-extracellular matrix (ECM) interactions are crucial for functional tissue constructs.
• Existing bioprinting methods often fail to achieve the high cellular density needed for effective biophysical cues.
• Current cell sheet fabrication relies on specialized substrates and external stimuli, limiting accessibility and scalability.

Purpose of the Study:

• To develop a novel, simplified method for creating dense, self-assembled cell sheets.
• To enable the formation of tissue constructs using readily available tissue culture plates and a pH trigger.
• To assess the viability, maturation, and ECM preservation during the cell sheet formation process.

Main Methods:

• A new technique utilizing a simple pH trigger for cell delamination and self-assembly into cell sheets.
• Application of the method to C2C12 myoblast cells, which are capable of syncytialization and fusion.
• Evaluation of cell viability, maturation, and ECM preservation post-delamination and self-assembly.

Main Results:

• The pH trigger successfully induced rapid delamination of cells as a continuous layer, forming a dense cell sheet.
• The process minimally impacted cell viability and maturation, preserving essential ECM components for sheet adhesion.
• Stacked constructs (double- and quadruple-layer) were successfully formed, demonstrating potential for thicker grafts.

Conclusions:

• This pH-triggered self-assembly method offers a simple, efficient, and accessible approach to generating dense cell sheets.
• The technique preserves cell integrity and ECM, facilitating the creation of multi-layered constructs for tissue regeneration.
• The developed cell sheets serve as promising platforms for advanced in vitro models and therapeutic applications.