Quantitative Capsule Visualization

Capsule was induced based on the original protocol described by Granger D.L. et al. (75 (link), 76 (link)). Overnight cultures were washed twice with PBS, resuspended in the DMEM culture media (Corning, Corning, NY) with addition of 10% FBS (Neuromics, Edina, MN), and transferred to 6-well plates with 10⁶ cells in each well. Cells were incubated for 5 days at 37°C with 5% CO₂, stained with India ink, and then observed under the Leica DMi8 inverted fluorescence microscope with a 100× objective. The size of the capsule was quantified using ImageJ software by measuring the width of the halo created by the capsule, which is visualized by negative staining with India ink.