Physics of cell adhesion: some lessons from cell-mimetic systems

Cell adhesion involves complex interactions between physical forces and cellular signaling. Established research has explored how cells respond to mechanical cues, but the precise mechanisms linking adhesion to intracellular structures remain unclear. This gap motivated a deeper investigation into the physical principles underlying cell adhesion. Prior studies have shown that adhesion is influenced by attractive and repulsive forces, but the role of cytoskeletal networks is less understood. No prior work had resolved how adhesion domains coordinate with actin and microtubules to generate forces. This uncertainty drove a focus on cell-mimetic systems to clarify these interactions. The need to understand how cells adapt adhesion strength in response to external forces remains a key challenge. This paper addresses these unresolved questions by analyzing physical rules governing cell adhesion.

The aim of this study is to review the physical principles governing cell adhesion through the lens of cell-mimetic systems. The specific problem is understanding how cells balance attractive and repulsive forces to maintain adhesion. This work seeks to clarify how adhesion domains interact with intracellular structures like actin and microtubules. The motivation stems from the need to explain how cells generate strong forces with minimal adhesion molecules. The study also aims to explore how adhesion strength adapts to external forces. The focus is on the role of exocytosis and endocytosis in modulating adhesion. The goal is to demonstrate how these physical rules apply to real cellular systems. This approach allows for a synthesis of biophysical and biochemical mechanisms.

The study uses a review approach to synthesize findings from cell-mimetic systems. It analyzes the competition between short-range attractive and medium-range repellant forces. The methods include examining how elastic stresses influence cell envelope deformation. The review considers how adhesion domains couple to actin and microtubule networks. It evaluates the role of exocytosis and endocytosis in adjusting CAM density. The study also investigates protease-mediated changes in CAM-cytoskeleton links. The focus is on how adhesion domains function as biochemical reaction centers. The review approach integrates data from multiple experimental systems.

Key findings show that adhesion domains couple to actin and microtubule networks to generate strong forces. These domains allow cells to manipulate other cells via filopodia over micrometer distances. Adhesion strength adapts to external forces within seconds through CAM density changes. Exocytosis and endocytosis modulate CAM levels to adjust adhesion. Protease activity can dismantle CAM-cytoskeleton links. Adhesion domains act as local and global biochemical reaction centers. Actin-microtubule crosstalk stabilizes polarized cell shapes. Axon growth is guided by antagonistic signaling pathways.

The synthesis of findings suggests that adhesion domains are crucial for coupling to intracellular structures. These domains enable cells to generate forces with minimal CAMs. The study highlights how adhesion strength can be rapidly adjusted. The role of exocytosis and endocytosis in modulating CAM density is emphasized. Adhesion domains serve as biochemical reaction centers, controlling enzyme activity. Actin-microtubule interactions at adhesion foci stabilize cell shapes. Axon guidance is influenced by antagonistic signaling pathways. These findings provide a framework for understanding adhesion in cellular systems.