Medulloblastoma 3D scaffold-only (3D-SF) cultures. All data here are from MB-1.A. Representative immunofluorescence images of 3D scaffold-only (3D-SF) models. (a), A representative Live/Dead-stained image of a 3D model at 24 hr post cell-seeding, showing randomly distributed single live cells (green) throughout the scaffold that auto-fluoresced in red. (b-e), Representative 3D models triple-stained for TUJ1 (green), GFAP (red) and nuclei DAPI (blue), showing tumor spheroids (greenish) anchored within the pores of the scaffold grew in size over time, e.g, b-1wk, c-2wk, d-3wk, e-4wk. Note that the silk material autofluoresced in blue. Scale bar, 100 μm. B. Flow cytometry-measured cell percentages from MB 2D vs. 3D cultures of 3wks in NE media. Stem cell markers, Nestin and CD133 showed significantly higher cell proportions in 3D than 2D cultures, whereas differentiated cells such as TUJ1+ neuronal-like or GFAP+ glial-like cells showed no difference.