Fig. 8: Analysis of hFOB spheroid pressurization experiment on the ISS.

a Representative fluorescence images of hFOB spheroids encapsulated in collagen gels. On the ISS, the spheroids were pre-treated with 100 ng ml⁻¹ of BMP2 stimulation for 3 h (right) and subjected to 1 h of 0, 2, and 4 psi. The samples were fixed and stored at -20 °C on the ISS and immunostained for DAPI, F-actin, pSMAD1/5/9, and YAP on the ground. Scale bar is 100 µm. b Plots of relative fluorescence intensity of F-actin (left), pSMAD1/5/9 (middle), and YAP (right) for hFOB spheroids subjected to different levels of compressive stress and with (red) or without (gray) BMP2 stimulation. c Plots of relative fluorescence intensity for BMP2-stimulated hFOB spheroids subjected to 1 h of 0, 2, and 4 psi on the ground (gray) and on the ISS (red). n = 6–16 spheroids per condition. *p < 0.05, **p < 0.01, ***p < 0.001.