Seven-year study of viability and absolute counts in cord blood units by flow cytometry in Greece

Assessing CD34+ cell viability and absolute counts, at different stages of processing allows for accurate quality control. Alterations in the cryopreservation or collection technique can be spotted in their effect on CD34+ cell viability and absolute counts. Products that are cryopreserved for lengthy periods, such as cord blood samples, can be assessed for quality using the single platform flow cytometry methodology1, 2. Flow cytometric analysis was performed on post freeze cord blood samples. Samples were analyzed, using the double-colour single platform variant of the ISHAGE guidelines with the addition of the viability dye 7-AAD. Prior to sample preparation, we ensured that the white blood cells (WBC) concentration was not greater than 30x109 WBC cells/L.