Hepatocyte cryopreservation: Is it time to change the strategy?

Table 1 Summary of freeze-rate comparison studies

Species	Cryoprotectant	Freeze rate	Storage temperature	Ref.
Human	DMSO	-1°C/min	-80°C	[55]
Rat	DMSO	-1°C/min to -38°C (with cooling shock) then liquid nitrogen	Liquid nitrogen	[61]
Dog, monkey, human	DMSO	-1.9°C/min from 4°C to -30°C, then -30°C from -30°C to -150°C	Liquid nitrogen	[57]
Rat	DMSO	-38°C/min	Liquid nitrogen	[59]
		-2°C/min
		Slow variable
		Optimized variable rate
Human	DMSO	-1.9°C/min from 4°C to -30°C, then -30°C from -30°C to -150°C	Liquid nitrogen	[51]
Rat	DMSO	Cooling in 10 min down to 0°C, 8 min at 0°C, in 4 min down to -8°C, in 0.1 min down to -28°C, in 2 min down to -33°C, in 2 min up to -28°C, in 16 min down to -60°C, in 4 min down to -100°C (variable rate)	Liquid nitrogen	[60]
Human	DMSO	Variable rate	Liquid nitrogen	[6]
Dog, monkey, human	DMSO	-1.9°C/min from 4°C to -30°C, then -30°C from -30°C to -150°C	Liquid nitrogen	[58]
Rat	DMSO	Variable rate	Liquid nitrogen	[39]
Pig	DMSO	Optimized[59]	Liquid nitrogen	[22]
		Modified variable

DMSO: Dimethylsulfoxide.