Fig. 5

Results from drug substance batch quality control analyses. a Live cell count, vitality, viability and ABCB5⁺ cell content of the 66 produced drug substance batches as determined before cryopreservation, shown by the number of the passage at which the ABCB5⁺ cells were isolated from the mixed culture. b Anti-inflammatory and proangiogenic potency of ABCB5⁺ mesenchymal stromal cells (MSCs) as measured by secretion of interleukin-1 receptor antagonist (IL-1RA) after stimulation by M1-polarized macrophages (IL-1RA secretion assay; given as ratio to IL-1RA secretion observed with unstimulated ABCB5⁺ MSCs), secretion of vascular endothelial growth factor (VEGF) after 48-h culture under hypoxic conditions (VEGF secretion assay; *value above upper limit of assay range, i.e., > 1500 pg/ml), and capillary structure formation in extracellular matrix (tube formation assay; red bar segments indicate the batches that failed to clearly form capillary structures). Error bars indicate means ± SD