Fig. 3. Overview of the SPHEROIDS experiments. A) The SPHEROIDS study consisted of a space experiment that was conducted for two weeks on the ISS, a ground control, and an additional RPM experiment. B) Set of analyses that were done after the experiments. C-F) Morphology of space-grown EA.hy926 cells harvested from the flight hardware: Adherent cells (AD) after 14 d (C), multicellular spheroids (MCS) (D) and tube-like structures (TS) after 7d (E,F). G) Morphology of EA.hy926 cells cultured for 12 d on the RPM and (H) under 1g conditions. I) Adherently growing EA.hy926 cells after 5 d in space. J) A multicellular tube harvested from the 7-day space samples. ECs were stained with Sirius Red (showing collagen in red). K) Laminin staining of a tubular structure, grown for 5 d in space. Scale bars: 35 µm. Parts of the Fig. were drawn by using pictures from Servier Medical Art. Servier Medical Art by Servier is licensed under a Creative Commons Attribution 3.0 Unported License (https://creativecommons.org/licenses/by/3.0/).