Scaffold-Free Tissue Self-Assembly in Microgravity (2D Cross-Section)

Small cell spheroids float inside a 2D cross-section of a virtual bioreactor and behave like viscous liquid droplets: differential adhesion between their surfaces pulls them together and fuses touching spheroids into a single larger, rounder construct, exactly as tissue-engineering labs use rotating-wall-vessel and orbital bioreactors to grow scaffold-free tissue on the ISS. Switch gravity from orbital microgravity to a 1 g Earth bench and watch the same culture sediment to the chamber floor and flatten under its own weight instead of self-assembling into a round construct — the real reason spaceflight biomedical research exists for regenerative medicine. A live timeline tracks fusion events and average sphericity as the culture evolves.