Leukapheresis cell concentration adjustment required for a successful recovery of HSC after cryopreservation

Role of flow cytometry in evaluation of the cellular therapy products used in haematopoietic stem cell transplantation

“…According to the Joint Accreditation Committee of International Society of Cellular Therapy (JACIE) standards, enumeration of viable CD34+ cells must be performed in fresh PBSC products to access the graft quality 15 . Minimal CD34+ cell count for one transplantation is ≥2 × 10 6 CD34+ cells/kg of recipient's body weight, while the optimal is 5 × 10 6 CD34+ cells/kg of body weight, which is associated with faster recovery of neutrophil and platelet count after transplantation 16,17 …”

“…This is especially important when performing multiple analysis in one step (e.g., enumeration of lymphocytes subpopulation). In addition to individual Ab, there are commercial kits that contain predefined Abs labelled with fluorochromes and reagents for determining cells of interest, for example, for determining HSC or lymphocyte subpopulations 16,37,38 . The advantage of these kits is that they contain pre‐assembled Ab panels, which facilitates the creation and implementation of protocols in laboratories that have no experience with setting up in‐house methods.…”

“…15 Minimal CD34+ cell count for one transplantation is ≥2 Â 10 6 CD34+ cells/kg of recipient's body weight, while the optimal is 5 Â 10 6 CD34+ cells/kg of body weight, which is associated with faster recovery of neutrophil and platelet count after transplantation. 16,17 Although laboratories for quality control in transplant centres use different protocols for determining CD34+ cells, the protocol of International Society of Hemotherapy and Graft Engineering (ISHAGE) is the most commonly used (Figure 1). 18 This protocol has been continuously updated, by introducing counting beads and including viability dyes.…”

“…In addition to individual Ab, there are commercial kits that contain predefined Abs labelled with fluorochromes and reagents for determining cells of interest, for example, for determining HSC or lymphocyte subpopulations. 16,37,38 The advantage of these kits is that they contain pre-assembled Ab panels, which facilitates the creation and implementation of protocols in laboratories that have no experience with setting up in-house methods. Furthermore, some manufacturers offer software for acquisition and analysis which have an auto-gating algorithm for isolation of the cells of interest, which also contributes to more user-friendly cell analysis, for example, BD FACSCanto Clinical software (BD Bioscience, San Jose, CA).…”

Effects of extended transport on cryopreserved allogeneic hematopoietic progenitor cell (HPC) product quality and optimal methods to assess HPC stability

“…Previous studies have reported decreases in post‐thaw viabilities to as low as 24%–31% from viabilities of 70%–100% prior to cryopreservation 2,3 . A number of variables from the time of collection through the cryo‐thaw process may impact post‐thaw recoveries, including graft transport durations, transport and storage conditions, and cryopreservation techniques 4–6 . Nevertheless, the impact of low post‐thaw viability on HPC engraftment has been controversial 7 .…”