Soft yet Sharp Interfaces in a Vertex Model of Confluent Tissue.

Area of Science:

• Cell biology
• Biophysics
• Tissue engineering

Background:

• Dense biological tissues often contain distinct cell populations.
• Maintaining sharp boundaries between these populations is crucial for tissue function.
• The biophysical mechanisms underlying boundary formation are not fully understood.

Purpose of the Study:

• To investigate how dense biological tissues maintain sharp boundaries between coexisting cell populations.
• To explore the role of cell topology and tissue surface tension in boundary formation.
• To understand the relationship between mechanical properties and interface sharpness.

Main Methods:

• Utilized a simple vertex model for cells.
• Focused on topological properties and tissue surface tension.
• Analyzed neighbor-based interaction rules and cell regulation of adhesivity and tension.

Main Results:

• Cells can support unusual interfaces by independently regulating adhesivity and tension.
• Mechanical and fluctuation-based measurements of effective surface tension yield different results.
• This leads to interfaces that are mechanically soft but exhibit extreme sharpness.

Conclusions:

• Cellular regulation of adhesion and tension, combined with interaction rules, enables sharp tissue boundaries.
• The distinct results from different surface tension measurements highlight the complex nature of cellular interfaces.
• These findings offer insights into tissue morphogenesis and stability.