Exosome Signaling — 2D Ligand Field & Receptor-Occupancy Model

This companion view represents the same ESCRT-mediated exosome pathway as a set of 2D fields instead of 3D particles: budding necks on a donor-cell cross-section still constrict and undergo scission exactly as in the 3D model, but every released exosome now injects ligand mass into a 1D advection-diffusion-decay concentration field that crosses the extracellular space toward a recipient-cell cross-section. Receptor occupancy on the recipient is integrated directly from the mass-action ODE (a deterministic mean-field solve, not a per-particle Monte-Carlo simulation), and the same ultrasensitive Hill function converts occupancy into a downstream signal. Tune ESCRT constriction rate, ligand density, transport speed and receptor off-rate and watch the field profile, occupancy and signal respond live.