Genetic lesions disrupting calreticulin 3′-untranslated region in JAK2 mutation-negative polycythemia vera

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Overview of T-cell depletion in haploidentical stem cell transplantation

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Transplantation in the onco-hematology field: Focus on the manipulation of αβ and γδ T cells

γ/δ T cells represent a subset of T cells expressing a T cell receptor (TCR) variant composed of gamma and delta chains. The γ/δ TCR is expressed by 2-10% of all T cells in human peripheral blood, whereas the majority of T cells express α/β TCRs. γ/δ T cells display a range of innate effector functions including rapid secretion of chemokines and cytokines, as well as target cell lysis. Recent interest has focused on the function of γ/δ T lymphocytes in allogeneic transplantation in the onco-hematology field. Several studies, in vitro and in vivo, suggest that γ/δ T lymphocytes are potential beneficial effector cells in the context of hematopoietic stem cell transplantation (HSCT). In addition, in this review, we discuss the depletion of α/β T lymphocytes in the graft for allogeneic transplantation. In fact, an efficient TCR α/β cell depletion potentially reduces the risk of GvHD. Furthermore, TCR α/β T cell depletion, especially with immunomagnetic negative selection, retains other potential beneficial effector cells in the graft, such as γ/δ T cells, NK cells, and stem cells. These "facilitating" cells might facilitate engraftment, exert GvL effects, and reduce the risk for infections

Automated washing of human progenitor cells: Evaluation of apoptosis and cell necrosis

BACKGROUND: High-dose chemotherapy followed by reinfusion of autologous stem cells harvested from peripheral blood has been increasingly applied for a variety of disorders. The critical importance of cell dose in the clinical outcome, after transplant, has motivated the need to develop techniques aimed at reducing cell losses and increasing reproducibility. OBJECTIVES: The aim of this study is to evaluate the efficacy of the Sepax S-100 device to process thawed HPC-A products in comparison with manual procedure. METHODS/MATERIALS: We have analysed viability, total nucleated cells (TNC), haematopoietic progenitors and CD34+ cells recovery. RESULTS: The TNC and CD34+ cells recovery in the automatic procedure was of 91.9% (73-100; SD ± 12.60) and 86.7% (69-100; SD ± 10.21), respectively. Instead the recovery of TNC and CD34+ cells using the manual method was of 84.7% (47-100; SD ± 22.9) and 80.29% (23-100; SD ± 25.96). The results, obtained from the assessment of viability of CD34+ both 7-AAD)+ and AnnV+ showed a high percentage of necrosis and apoptosis in this cell subset by using the manual procedure in respect to the Sepax automated system. CONCLUSION: Overall, our data suggest that the automated washing procedure is safe and suitable for processing of thawed HPC-A products and can be daily used in clinical routine

A new system for quality control in hematopoietic progenitor cell units before reinfusion in autologous transplant.

BACKGROUND: In our Center, the cell viability, the integrity of the bag, and the clonogenic assay were evaluated before the reinfusion of hematopoietic progenitor cells-apheresis (HPC-A). This quality control (QC) should be made 14 days before the reinfusion to the patient to have the result of the functional test on the proliferative capacity of hematopoietic progenitors. STUDY DESIGN AND METHODS: This study was designed to assess the potential of an automatic cell counting system (NucleoCounter NC-3000, ChemoMetec) in our clinical routine as a support of the clonogenic assay and the cytofluorimetric analysis for the QC of the cryopreserved HPC-A. The cell viability was evaluated by flow cytometry using the modified International Society of Hematotherapy and Graft Engineering protocol. The proliferative potential was assessed by specific clonogenic tests using a commercial medium. Furthermore, we evaluated the cellular functionality with NucleoCounter NC-3000, by using two protocols: "vitality assay" and "mitochondrial potential assay." RESULTS: The evaluation of the total nucleated cells in preapoptosis measured by 5,5,6,6-tetrachloro-1,1,3,3-tetraethylbenzimidazol-carbocyanine iodide (JC-1) assay showed a negative correlation (r=-0.43) with the total number of colonies (colony-forming unit [CFU]-granulocyte-macrophage progenitors plus burst-forming unit-erythroid progenitors plus CFU-granulocyte, erythroid, macrophage, megakaryocyte progenitors) obtained after seeding of 50 × 10(6) /L viable total nucleated cells. We observed a significant difference (p<0.0001) comparing the median number of colonies (166.70; SD, ± 136.36) obtained with a value of JC-1 less than 30% to the number of colonies (61.75; SD, ± 59.76) obtained with a value of JC-1 more than 30%. CONCLUSION: The evaluation of cell functionality by the use of the NucleoCounter NC-3000 is in agreement with results from clonogenic assay and can be considered an effective alternative in the routine laboratory