B-NHL spheroids obtained by using the cellular capsule technology. (A) Representative images of cell growth in alginate capsule shells over time for the various cell lines. Scale bar, 100 µm. (B) Percentage of SUDHL4 and HLY1 cell death measured after shell dissolution and spheroid dissociation at 6, 8, and 12 days after encapsulation. To evaluate cell death, propidium iodide (PI) (10 µg/mL) was added to the cell suspension and PI fluorescence was analyzed by flow cytometry (n = 3). (C) Immunostaining showing the repartition of proliferating and apoptotic cells in SUDHL4 and HLY1-derived spheroids at 8 or 12 days post-encapsulation. Five micrometers thick sections were stained with anti-Ki67 (Ki67, in green) and anti-cleaved caspase 3 (CC3, in red) to identify proliferating and dead cells, respectively. Nuclei are depicted in blue (Dapi staining). Scale bar, 100 µm.