Kalodimou Vasiliki
Background: flow cytometry is a technique of quantitative single cell analysis. It can process measurements on thousands cells in a few seconds. Since different cell types can be distinguished by quantization structural features, flow cytometry can be used to count cells of different types in a mixture. Cord blood samples, has posed additional challenges over the years particularly due to the presence of varying number of nucleated red blood cells (RBC) and the extended age of the samples at the time of CD34+ cells enumeration. Method: the aim in our study was to prove that time has no effect in CD34+ cells storage, efficacy and viability using flow cytometry as a quantitative single cell analysis. To enhance further our study, post-freeze white blood cells (WBC) counts from an automated haematology analyzer were compared with WBC derived after cytometric analysis. Results: four-thousands cord blood samples were analyzed for absolute viable CD34+ cells, WBC and their viability. Viable CD34+ cells were enumerated using single platform flow cytometry and the molecular exclusion dye 7-amino actinomycin D (7- AAD). Conclusion: cryopreservation and processing of autologous stem cells collection, assessing CD34+ cell viability and absolute counts, found to remain the same during periods of time. Measuring CD34 +cell viability allows us the quality of control assessments of stem cells processing.
