#12 · Systems biology

Mechanistic models tie exosome cargo, viscosity and ion pumping to cell-scale behaviour

The dominant thread is the use of minimal, mechanistic models to identify how a single physical or biochemical parameter governs a cell-scale outcome. A published model of leader-follower migration shows that exosome cargo size trades signal frequency against signal strength, producing an optimal size that maximises follower chemotaxis speed. A preprint on the mouse node proposes that secreted macromolecules raise near-surface viscosity, amplifying cilia drag so that flow direction is sensed reliably. A second preprint analyses a two-compartment pump-leak model, deriving analytic equilibria and testing stability and sensitivity to NKA placement. The items are heterogeneous, and only the exosome study addresses migration directly. What is new is the explicit emphasis on parameter placement and trade-offs, namely cargo size, viscosity amplification and pump location, as determinants of optimality and robustness.