Factors influencing cord blood viability assessment before cryopreservation

Abstract

CB cell populations exhibit differential time- and temperature-dependent susceptibility to in vitro cell death; consequently, global viability measurements using TB, AO/PI, or 7-AAD (Tot-AAD) significantly underestimate (4-24 degrees C) or overestimate (24-37 degrees C) CD34+ viability and CFC recovery. Our results demonstrate the limitations of global viability assessment with TB, AO/PI, and total AAD; endorse the routine use of CD34+ cell viability measurements; emphasize the importance of temperature control during shipment; and have implications with regard to establishing acceptable "cutoff" values for viability measurements and CB collection through processing time.