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Hematopoietic Recovery (hematopoietic + recovery)
Selected AbstractsPositive selection for CD90 as a purging option in acute myeloid leukemia stem cell transplants,CYTOMETRY, Issue 1 2008Nicole Feller Abstract Background: Several studies showed the benefit of purging of acute myeloid leukemia (AML) stem cell transplants. We reported previously that purging by positive selection of CD34+ and CD133+ cells resulted in a 3,4 log tumor cell reduction (TCR) in CD34, and/or CD133, AML, but has been shown to be potentially applicable in only about 50% of cases. Similar to CD34 and CD133, CD90 marks the hematopoietic CD34 positive stem cells capable of full hematopoietic recovery after myeloablative chemotherapy, and therefore, in the present study, we explored whether a similar purging approach is possible using CD90. Methods: CD90 expression was established by flowcytometry in diagnosis AML on the clonogenic AML CD34+ blast population by flow cytometry. Positivity was defined as >3% CD90 (CD34+) expression on blasts. For the calculation of the efficacy of TCR by positive selection, AML blasts were recognized by either prelabeling diagnosis blasts with CD45-FITC in spiking model experiments or using expression of leukemia associated marker combinations both in spiking experiments and in real transplants. Results: In 119 patients with AML and myelodysplastic syndrome, we found coexpression of CD34 and CD90 (>3%) in 42 cases (35%). In AML patients 60 years or younger, representing the patients who are eligible for transplantation, only 23% (16/69) of the patients showed CD90 expression. Positive selection for CD90 in transplants containing CD90 negative AML resulted in a 2.8,4 log TCR in the models used. Conclusions: Purging by positive selection using CD90 can potentially be applied effectively in the majority of AML patients 60 years or younger. © 2007 Clinical Cytometry Society [source] Autologous peripheral blood stem cell collections in children weighing less than 10 Kg with solid tumors: Experience of a single centerJOURNAL OF CLINICAL APHERESIS, Issue 2 2005Hyun-Jung Cho Abstract There have only been a few reports and limited performance of peripheral blood stem cell (PBSC) collection in very small children weighing less than 10 kg. In this study, we intended to evaluate the safety and yield of PBSC collection, with the efficacy of PBSC transplantation (PBSCT) in the smallest children with solid tumors. From January 1998 to February 2004, 173 children underwent PBSC collection in Samsung Medical Center, Korea. Of these, 15 (8.7%) children weighed less than 10 kg and their clinical diagnoses were neuroblastoma (10 cases), rhabdoid tumor (2 cases), rhabdomyosarcoma (2 cases), and Wilms tumor (1 case). PBSCs were collected following chemotherapy plus G-CSF mobilization. The median age and weight at the time of apheresis were 15 months and 9 kg, respectively. The median number of PBSC collection procedures per case was 4 (range, 2,7). The median cell yield per apheresis product was 0.95 (range, 0.01,33.32) × 106/kg CD34+ cells and 1.96 (range, 0.12,23.39) × 108/kg mononuclear cells. No complications associated with citrate toxicity and other adverse effect were observed during the procedures. After high-dose chemotherapy, 14 patients were reinfused with PBSCs alone and all showed successful hematopoietic recovery. We concluded that PBSC collection would be a safe and practical procedure, even when done in the smallest children, provided that adequate intravascular fluid volume and circulating red cell mass were maintained. Also, the use of PBSCs to support high-dose chemotherapy was well tolerated and might enhance hematological recovery in the smallest children showing the excellent efficacy of PBSCT. J. Clin. Apheresis © 2005 Wiley-Liss, Inc. [source] Hematopoietic progenitor cells (HPC) and immature reticulocytes evaluations in mobilization process: new parameters measured by conventional blood cell counterJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2006J.F.A. Noronha Abstract Monitoring the timing of leukapheresis in peripheral blood stem cells (PBSC) mobilization is an important clinical decision that requires an accurate analytical tool. The present study assessed hematopoietic progenitor cells (HPC) and immature reticulocyte fraction (IRF) counts provided by a routine automated blood counter as potential parameters for predicting the appropriate time for harvesting. The HPC and IRF values were compared with white blood cell (WBC) and CD34+ cell counts obtained by flow cytometry in 30 adult patients with hematological malignancies undergoing PBSC mobilization. It was observed that there was a significant correlation between HPC counts and CD34+ cells in peripheral blood counts (r=0.61, P=0.0003) and between the number of HPC and CD34+cells collected by leukapheresis (r=0.5733, P=0.0009). Comparing HPC, IRF, WBC, and CD34+ cells parameters as a sign of hematological recovery showed that the raise in immature reticulocytes counts preceded the increase of WBC (P=0.0002), HPC (P=0.0001), and CD34+ (P=0.0001) cells in peripheral blood counts. According to our results, HPC and IRF parameters may be integrated into clinical protocols to evaluate the timing of leukapheresis. IRF, as previously demonstrated in bone marrow transplantation, is the earliest sign of hematopoietic recovery in mobilization process. J. Clin. Lab. Anal. 20:149,153, 2006. © 2006 Wiley-Liss, Inc. [source] Retrospective comparison of mobilization methods for autologous stem cell transplantation in multiple myeloma,AMERICAN JOURNAL OF HEMATOLOGY, Issue 12 2009Hideki Nakasone The combination of cyclophosphamide and granulocyte-colony stimulating factor (G-CSF) has widely been used to mobilize hematopoietic stem cells (HSCs) for autologous stem cell transplantation (ASCT) for multiple myeloma (MM). Recently, however, alternative approaches such as G-CSF alone or etoposide followed by G-CSF have been investigated. We, therefore, retrospectively analyzed the effects of these mobilization methods on collection yield and disease outcome in ASCT for MM. We reviewed 146 MM patients from whom we intended to collect stem cells. For mobilization, 67, 58, and 21 patients received cyclophosphamide and G-CSF, etoposide and G-CSF, and G-CSF alone (including nonmyelosuppressive chemotherapy followed by G-CSF), respectively. Among them, 136 achieved the target number of HSCs (at least 2 × 106/kg). Lower creatinine and higher albumin levels at diagnosis were significantly associated with successful yield. A lower number of infused HSCs, use of the etoposide for mobilization and high ISS were associated with delayed hematopoietic recovery. The mobilization methods did not significantly affect either the successful collection of more than 2 × 106 CD34-positive cells/kg or PFS after ASCT. G-CSF alone was sufficient for stem cell mobilization for a single ASCT. The optimal approach to collect HSCs in MM remains to be elucidated. Am. J. Hematol., 2010. © 2009 Wiley-Liss, Inc. [source] The impact of CD34+ cell dose on platelet engraftment in pediatric patients following unmanipulated haploidentical blood and marrow transplantation,PEDIATRIC BLOOD & CANCER, Issue 6 2009Ying-Jun Chang PhD Abstract Objective Unmanipulated haploidentical blood and marrow transplantation has been developed as an alternative transplant strategy for pediatric patients with hematological diseases. The aim of this study was to investigate the effects of donor and recipient characteristics on hematopoietic recovery in pediatric patients following unmanipulated haploidentical transplantation. Methods Factors correlating with hematopoietic recovery in 133 pediatric patients after unmanipulated haploidentical transplantation were analyzed retrospectively. Results All patients reached an absolute neutrophil count of 500/µl in a median of 12 days (range, 9,49 days). One hundred thirty-three patients reached an untransfused platelet count of more than 20,000/µl in a median of 15 days (range, 7,180 days). Univariate analysis showed five factors associated with platelet engraftment. These were time to transplantation after diagnosis (P,=,0.072), infused nuclear cells/kg of recipient weight (P,=,0.028), CD3+ cells/kg of recipient weight (P,=,0.082), CD4+ cells/kg of recipient weight (P,=,0.083), and CD34+ cells/kg of recipient weight (P,=,0.012). Multivariate analysis showed that infused CD34+ cells/kg of recipient weight (CD34+ cells more than 2.42,×,106/kg vs. less than or equal to 2.42,×,106/kg, HR,=,1.733; 95% CI 1.222,2.549; P,=,0.002) were significantly associated with an increased risk of platelet engraftment. Patients receiving a CD34+ cell dose more than 2.42,×,106/kg had a short time [12 days (range, 7,176 days)] to achieve an untransfused platelet engraftment, compared to 18 days (range, 7,180 days) in patients receiving a lower dose (P,<,0.001). Conclusions Our results suggest that low number of CD34+ cells in allografts is a critical factor associated with delayed platelet engraftment after unmanipulated haploidentical transplantation in pediatric patients. Pediatr Blood Cancer 2009;53:1100,1106. © 2009 Wiley-Liss, Inc. [source] | ||||||||||