Expansion of human mesenchymal stem cells on microcarriers

Culture of human mesenchymal stem cells on microcarriers in a 5 l stirred-tank bioreactor

“…The microcarrier seeding density chosen, 6000 cells.cm -2 , equates to ~ 5 cells/bead. This was chosen based on preliminary work (Hewitt et al 2011) and for comparability with standard T-flask culture where the seeding density used is typically 5000 cells.cm -2 . In all cases reproducible results were obtained ( Figure 1 and Figure 2).…”

A Multicompartment Holder for Spinner Flasks Improves Expansion and Osteogenic Differentiation of Mesenchymal Stem Cells in Three-Dimensional Scaffolds

“…12,15,35 Of notice is the importance of maintaining an initial static period of 24 h to promote robust cell seeding onto the scaffolds, before starting stirring. This time was essential to prevent cell detachment and death (data not shown), and has been also referred by other authors like Hewitt et al 36 To prevent initial cell loss, other authors have opted to use initial low agitation speed, which was afterward increased. 7 MSCs 3D cultures in the multicompartment holder in spinner flasks were analyzed in what concerns cell viability, metabolic activity, proliferation, and spatial distribution.…”

Mixing theory for culture and harvest in bioreactors of human mesenchymal stem cells on microcarriers

“…Nevertheless, with cells growing at (λ K ) JS = ~ 30% of the microcarrier size, it may be that, as with animal cells in free suspension [9], hMSCs are more robust than has generally been perceived. 1) Estimated from reference [5]; 2) From reference [9]; 3) From reference [4]; From reference [7] since agitators in the DASGIP and Sartorius bioreactors are similar 3 blade, pitched turbines; 5) From reference [7] Table 1…”

“…Though there are some issues over the use of Kolmogorov's theory of isotropic turbulence because the Reynolds numbers, Re, are in the transitional regime (~ 10 3 < Re < ~ 10 4 ), it is the standard approach for considering the impact of fluid dynamic stress on organisms [4]. It suggests that provided the size of the biological entity, d E , which is suspended in the flow, is less than the Kolmogorov scale, λ K , the entity should not be damaged where…”

“…For cells on microcarriers, d E is considered to be the size of the microcarrier, d micro , typically ~ 200 µm, and earlier work showed that cell growth is not compromised provided λ K ≥ ~ 0.6d micro [4,6].…”