RESUMEN
BACKGROUND: Autologous hematopoietic progenitor cell (HPC) transplantation is currently the standard of care for a fraction of patients with newly diagnosed myelomas and relapsed or refractory lymphomas. After high-dose chemotherapy, cryopreserved HPC are either infused directly after bedside thawing or washed and concentrated before infusion. We previously reported on the comparability of washing/concentrating HPC post-thaw vs. infusion without manipulation in terms of hematopoietic engraftment, yet settled for the prior favoring cell debris and DMSO removal. For almost two decades, automation of this critical step of washing/concentrating cells has been feasible. As part of continuous process verification, we aim to evaluate reproducibility of this procedure by assessing intra-batch and inter-batch variability upon concentration of thawed HPC products using the Sepax 2 S-100 cell separation system. METHODS: Autologous HPC collected from the same patient were thawed and washed either in two batches processed within a 3-4 h interval and immediately infused on the same day (intra-batch, n = 45), or in two batches on different days (inter-batch, n = 49) for those patients requiring 2 or more high-dose chemotherapy cycles. Quality attributes assessed were CD34+ cell recovery, viability and CD45+ viability; CFU assay was only performed for allogeneic grafts. RESULTS: Intra-batch and inter-batch median CD34+ cell recovery was comparable (75% vs. 73% and 77% vs. 77%, respectively). Similarly, intra-batch and inter-batch median CD45+ cell viability was comparable (79% vs. 80% and 79% vs. 78%, respectively). Bland-Altman analysis describing agreement between batches per patient revealed a bias close to 0%. Additionally, lower HPC recoveries noted in batch 1 were noted as well in batch 2, regardless of the CD34+ cell dose before cryopreservation, both intra- and inter-batch, suggesting that the quality of the collected product plays an important role in downstream recovery. Intrinsic (high mature and immature granulocyte content) and extrinsic (delay between apheresis and cryopreservation) variables of the collected product resulted in a significantly lower CD45+ viability and CD34+ cell recovery upon thawing/washing. CONCLUSIONS: Automated post-thaw HPC concentration provides reproducible cell recoveries and viabilities between different batches. Implications of this work go beyond HPC to concentrate cell suspension/products during manufacturing of cell and gene therapy products.
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Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas , Humanos , Antígenos CD34 , Reproducibilidad de los Resultados , Criopreservación/métodos , Trasplante Autólogo , Supervivencia CelularRESUMEN
Accurate characterization of hematopoietic stem cells (HSC) products is needed to better anticipate the hematopoietic reconstitution and the outcome in patients. Although CD34+ viable cells enumeration is a key predictor of time to correction of aplasia, it does not fully inform about functionality of cells contained in the graft. CFU assay is the gold standard in vitro potency assay to assess clonogenicity of HSC and consists on the count and identification of colonies several days after culture in a semi solid media. Manual count of colonies with optic microscope is the most commonly used method but its important variability and subjectivity hinders the universal implementation of this potency assay. The aim of this study is to validate a standardized method using the STEMvision™ system, the first semi-automated instrument for imaging and scoring hematopoietic colonies, according to French and European recommendations. Results obtained highlight better performance criteria with STEMvision™ system than the manual method. This semi-automatic device tends to reduce the coefficients of variation of repeatability, inter-operator variability and intermediate precision. This newly available platform could represent an interesting option, significantly improving performances of CFU assays used for the characterization of hematopoietic progenitors.
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Ensayo de Unidades Formadoras de Colonias/instrumentación , Células Madre Hematopoyéticas/citología , Antígenos CD34/metabolismo , Automatización , Ensayo de Unidades Formadoras de Colonias/métodos , Células Madre Hematopoyéticas/metabolismo , HumanosRESUMEN
Scientific studies in oncology, cancer diagnosis, and monitoring tumor response to therapeutics currently rely on a growing number of clinico-pathological information. These often include molecular analyses. The quality of these analyses depends on both pre-analytical and analytical information and often includes the extraction of DNA and/or RNA from human tissues and cells. The quality and quantity of obtained nucleic acids are of utmost importance. The use of automated techniques presents several advantages over manual techniques, such as reducing technical time and thus cost, and facilitating standardization. The purpose of this study was to validate an automated technique for RNA extraction from cells of patients treated for various malignant blood diseases. A well-established manual technique was compared to an automated technique, in order to extract RNA from blood samples drawn for the molecular diagnosis of a variety of leukemic diseases or monitoring of minimal residual disease. The quality of the RNA was evaluated by real-time quantitative RT-PCR (RQ-PCR) analyses of the Abelson gene transcript. The results show that both techniques produce RNA with comparable quality and quantity, thus suggesting that an automated technique can be substituted for the reference and manual technique used in the daily routine of a molecular pathology laboratory involved in minimal residual disease monitoring. Increased costs of reagents and disposables used for automated techniques can be compensated by a decrease in human resource.
RESUMEN
BACKGROUND: Washing out of thawed autologous grafts, before reinfusion in poor-prognosis cancer patients who undergo high-dose chemotherapy, is desirable. The procedure allows for the reduction of infused dimethyl sulfoxide (DMSO) quantities and the performance of biologic controls on the infused cell product. STUDY DESIGN AND METHODS: Three-hundred four patients were treated with intensified chemotherapy and autologous transplantation at a single institution. Fifty-four of them received washed cell products, because three or more bags were to be reinfused. The recently available, closed, automated, and current good manufacturing practice-compliant device (CytoMate, Baxter Oncology) was used for this purpose. RESULTS: The performances of the device were similar to previously reported results, with greater than 75 percent CD34+ cell recovery. Neutrophil and platelet (PLT) recoveries were similar in the group of patients receiving washed cells and in the group of patients for whom cell products were extemporaneously thawed at the bedside. Adverse events that are typically reported after DMSO infusion were significantly less frequent and less severe in patients who received washed cells. Finally, the nurse staff on the transplant ward reported a decreased workload and more satisfactory procedure when infusing washed cell products. CONCLUSION: The CytoMate device allows for a significant reduction in DMSO infusion, with a diminished frequency and severity of immediate side effects and does not compromise neutrophil or PLT engraftment.