Table 2.

Main features of the culture systems and bioreactors employed for MSC manufacturing.

Features	Multilayered flasks	Stirred tank bioreactor	Rocking bioreactor	Fixed-bed bioreactor	Hollow fiber bioreactor
Homogeneity	No	Yes	Yes	No	Moderate (spatial concentration gradients)
Culture parameter control and monitoring	No	Yes	Yes	Yes	Yes
Scale-up	Limited	Moderate	Moderate (up to 500 L)	Moderate	Moderate
Contamination risk	High (open system)	Low (closed system)	Low (closed system)	Low (closed system)	Low (closed system)
Shear stress	No	High	Moderate	Low	Low
Oxygen transfer	Low	High	High	Moderate	High
Culture operation mode	Batch	Batch, fed-batch, perfusion	Batch, fed-batch, perfusion	Batch, fed-batch, perfusion	Perfusion
Cell harvesting	Easy	Difficult	Difficult	Difficult	Easy