Fig. 2

Viability and density of multipotent progenitor cells (MPCs) seeded on aligned NF scaffold. Edge-to-edge mosaic images of NF-seeded MPCs stained with Live/Dead (green/red) assay were obtained at 24 h post-seeding at (a,e,i) 0.5, (b,f,j) 1, (c,g,k) 5, and (d,h,l) 10 × 10³ (k) cells/cm²; scale bar = 100 μm. Evidence of NF-mediated cell alignment could be seen in the common orientation of the MPCs. e–h MPC density (presented as an exponential scale) as a function of culture time. MPC density scaled with initial seeding density at early time points (days 1 and 3), but eventually converged towards 1 k cells/cm² by day 9, except for the 10 k cultures. Cell aggregation on the scaffolds resulted in extreme local variations in cell density. MPC viability (i–l) varied widely at early time points. By day 9, 65% or more cells remained viable, and viability increased with initial seeding density