Fig 3. Viability (left) and viable cell number (right) of samples being warmed at 1°C a minute from -196°C, to the temperatures indicated, before being warmed rapidly to thaw in a water bath (in 2ml cryovials).

Data 24 h post-thaw. The rightmost sample (4°C), was warmed slowly until thaw. No significant difference was seen in viabilities. All samples warmed rapidly through the phase transition had significantly increased viable cell number over the samples warmed slowly (4°C sample), viable cell number was 16.3 ± 1.7 million cells/ml immediately prior to cryopreservation. N = 5 ± SD, significance defined as * = P<0.001, unpaired Student’s t-test.