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Bone Marrow Transplantation (2004) 33, 1083–1087 & 2004 Nature Publishing Group All rights reserved 0268-3369/04 $25.00 www.nature.com/bmt Progenitor cell mobilization Good and poor CD34 þ cells mobilization in acute leukemia: analysis of factors affecting the yield of progenitor cells D Pastore, G Specchia, A Mestice, A Liso, A Pannunzio, P Carluccio, C Buquicchio, G Greco, L Ciuffreda, G Pietrantuono and V Liso Hematology Section, Department DIMIMP, University of Bari, Italy Summary: The factors possibly affecting the collection of peripheral blood stem cells (PBSC) were evaluated in 104 de novo acute leukemia patients (66 myeloid and 38 lymphoblastic leukemias) in first cytological complete remission (CR); all patients achieved CR after first-line induction chemotherapy. The acute myeloid leukemia patients (AML) were given consolidation–mobilization chemotherapy with cytarabine, and daunoblastin or mitoxantrone or idarubicin; the acute lymphoblastic leukemia patients (ALL) were given consolidation–mobilization chemotherapy with cytarabine and etoposide. In all patients, the collection of PBSC was performed during recovery after giving consolidation chemotherapy and granulocyte colony-stimulating factor (G-CSF). Two main groups were considered according to the CD34 þ cells 106/kg b.w. collected, that is, poor mobilizers (PM), with a collection of o2 106/kg and good mobilizers, with a collection of 42 106/kg. Of 104 patients, 27 (25.9%) were PM; 20/27 had AML and 7/27 had ALL. At multivariate analysis, a lower CD34 þ cells count premobilization chemotherapy (CD34 steady state), the presence of FUO (fever of unknown origin) or infection, and a lower number of CD34 þ cells on the first day of collection correlated with poor mobilization. These results may enable early recognition of patients who may have poor mobilization, and aid selection of patients for different mobilization regimens. Bone Marrow Transplantation (2004) 33, 1083–1087. doi:10.1038/sj.bmt.1704437 Published online 12 April 2004 Keywords: acute leukemia; peripheral blood stem cell mobilization Peripheral blood stem cells (PBSC) are now widely used to restore hematopoiesis following high-dose chemotherapy in acute leukemia patients without an HLA-matched related donor.1–4 Compared with autologous bone marrow, PBSC Correspondence: Dr G Specchia, Hematology Section, Department DIMIMP, University of Bari, Piazza Giulio Cesare 11, Bari 70124, Italy; E-mail: [email protected] Received 5 June 2003; accepted 13 November 2003 Published online 12 April 2004 transplants are associated with a shorter period of aplasia and lower transplant-related mortality.5,6 PBSC are usually collected by apheresis during the recovery phase following chemotherapy plus granulocyte-colony-stimulating factor (G-CSF). A significant correlation between sustained hematologic engraftment and the quantity of reinfused CD34 þ cells has been reported, indicating that collection of CD34 þ cells is likely to be crucial for safe engraftment.7–10 The quantity of PBSC to be infused to achieve a prompt recovery post transplant remains controversial, but at least 2 106/kg CD34 þ cells are usually required in autologous stem cell grafts to ensure hematopoietic recovery after myeloablative chemotherapy.9–11 The number and type of premobilization chemotherapy or radiotherapy sessions, patient age and marrow involvement have been reported to affect mobilization in lymphoma, myeloma and cancer patients.12–18 However, data regarding PBSC collection in acute leukemia patients are limited.19–21 The purpose of this study was to identify CD34 cell mobilization factors (diagnosis, age, sex, CD34 cell count preconsolidation chemotherapy, type of chemotherapy, infections or fever of unknown origin (FUO), CD34 þ cells in the peripheral blood, white blood cells (WBC), mononuclear cells (MNC) on the first day of collection) in a series of 152 procedures performed on 104 de novo acute leukemia patients who achieved cytological complete remission (CR) after one cycle of chemotherapy. Patients and methods Patient population From February 1990 to March 2002, 104 patients with de novo acute leukemia in first cytological CR were eligible for consolidation–mobilization chemotherapy plus G-CSF, and underwent peripheral blood stem cell harvest; of these patients (50 males and 54 females, aged 15–61 years, median 40 years), 66 had acute myelogenous leukemia (AML) and 38 had acute lymphoblastic leukemia (ALL). The patient characteristics are listed in Table 1. The patients had been treated with induction therapy according to the GIMEMA protocols; the AML patients were treated with cytarabine 100 mg/m2 by i.v. infusion over 24 h for 10 consecutive days, etoposide 100 mg/m2 once daily i.v. for 5 consecutive days and daunorubicin 50 mg/m2 (26 patients) or mitoxantrone 12 mg/m2 (20 patients) or idarubicin CD34 þ cells mobilization in acute leukemia D Pastore et al 1084 Table 1 Clinical data of 104 patients undergoing mobilization procedures AML ALL Number of patients Sex (male/female) Median age (years) 66 34/32 46 (16–59) 38 16/22 40 (14–58) Induction chemotherapy (no. of patients) DNR+E+ARA-C (26) MITOX+E+ARA-C (20) IDA+E+ARA-C (20) VCR+DNR+PRD (38) Consolidation-mobilization therapy (no. of patients) DNR+ARA-C (26) MITOX+ARA-C (20) IDA+ARA-C (20) E+ARA-C (38) Interval from diagnosis to PBSC collection (days) 70 (58–85) 64 (60–72) Interval from consolidation chemotherapy to PBSC collection (days) 18 (17–21) 14 (13–15) E ¼ etoposide. 10 mg/m2 once daily (20 patients) for 3 consecutive days. The ALL patients were treated with vincristine 1.4 mg/m2 i.v. weekly for 5 weeks, daunorubicin 30 mg/m2 once daily for 3 days for three cycles overall, L-asparaginase 6000 UI/ m2 once daily subcutaneously for 10 days and prednisone 60 mg/m2 for 30 days. Before PBSC collection, all patients had received one chemotherapy cycle as induction and one consolidation–mobilization chemotherapy cycle. The day before starting consolidation chemotherapy, the CD34 þ peripheral blood cells count (CD34 steady state) was determined. PBSC mobilization AML patients were mobilized with cytarabine 500 mg/m2 twice daily i.v. for 6 days and idarubicin 10 mg/m2 (20 patients) or mitoxantrone 12 mg/m2 (20 patients) or daunorubicin 50 mg/m2 once daily i.v. for 3 days (26 patients). ALL patients (38) were mobilized with cytarabine 2 g/m2 i.v. twice daily for 2 days and etoposide (E) 150 mg/ m2 once daily i.v. for 3 days. In all patients, G-CSF was administered subcutaneously at a dose of 5 mg/kg daily, starting 10 days after the start of chemotherapy and continuing until the day before the apheresis. PB CD34 þ cell measurements were performed during the recovery phase after chemotherapy when a white blood count of 42 109/l was reached. Immediately prior to PBSC collection procedures, the PB with blood cell (WBC), MNC and CD34 þ counts was determined and correlated with the CD34 þ harvested. PBCS were collected using blood cell separators CS3000 þ (Baxter-Fenwal, Deerfield, IL, USA) using a small-volume collection chamber; blood was collected via a central venous access device (60 patients) or from peripheral veins (44 patients), and a median of 8 l of blood was processed per apheresis. In all, 48 patients underwent one apheresis and 56 two apheresis procedures. CD34 enumeration was performed on viable cells with a dual-platform version of the ISHAGE protocol;22 briefly, the WBC were measured with an automated hematology analyzer and, if necessary, samples were diluted; 100 ml Bone Marrow Transplantation aliquots of the sample, containing between 5 106 and 10 106 cells, were incubated for 30 min at 41C with 10 ml of phycoerythrin (PE)-conjugated anti-CD34 (HPCA-2), 10 ml of fluorescein isothiocyanate (FITC)-conjugated anti-CD45 (2D1) (BD Biosciences) and 20 ml of 7-aminoactinomycin D (final concentration 1 mg/ml). After incubation, the red cells were lysed and cells were analyzed by fluorescenceactivated cell sorting (FACScan, Becton Dickinson) using the CellQuest Software. Statistical analysis The clinical characteristics of the two groups of patients, good mobilizers (GM) and poor mobilizers (PM), were compared using two-tailed Fisher’s exact test for categorical variables and Student’s t-test or the Mann–Whitney test for continuous variables. Pearson’s test was used to correlate the CD34 steady state and CD34 at the first day of apheresis with the number of CD34 þ cells collected. The binary logistic regression model was used to analyse parameters found to be statistically significant at univariate analysis. Only P-values o0.05 were considered statistically significant. All the statistical analyses were carried out using the Statistical Package for Social Sciences (SPSS) package, version 11.0 for Windows. Results Correlations between the number of PBSC collected and patient diagnosis, sex, CD34 þ cells in the peripheral blood premobilization chemotherapy (CD34 þ steady state), chemotherapy, FUO or clinically or microbiologically documented infection during the neutropenic phase after consolidation chemotherapy, WBC, MNC and CD34 þ blood cells at the first day of collections were determined by multivariate analysis. According to the total collected CD34 þ cells 106/kg b.w., two main groups were considered that is, PM, with a collection of o2 106/kg (27/104 pts, 25.9%), and GM, with a collection of 42 106/kg (77/104 pts, 74.1%) (Table 2). There was no CD34 þ cells mobilization in acute leukemia D Pastore et al 1085 Characteristics of 104 patients and outcome of mobilization Patients AML ALL Median age (years) Sex M Sex F Median CD34+ steady-state 106/l (range) Median WBC on the first day of collection 109/l (range) Median MNC on the first day of collection 109/l (range) AML treated with DNR (26) AML treated with IDA (20) AML treated with MITOX (20) FUO or infection PB CD34+ cells at the first day of collection 106/l (range) Blood volume processed (l) Number of apheresis procedures per patient correlation between the diagnosis (AML vs ALL) and PM or GM: 20/66 (30.3%) PM in AML vs 7/38 (18.4%) in ALL (not significant). There was no statistically significant correlation between the two groups regarding sex (22.2% of females vs 20% of males were PM), age (median age 38 vs 46 years in GM and PM, respectively), WBC at the first day of collection (7.8 109 vs 5.6 109/l in GM and PM, respectively), MNC at the first day of collection (2.5 109 vs 1.8 109/l in GM and PM). In the GM group, 56 patients underwent one apheresis and 21 patients underwent two apheresis procedures; all 27 PM patients underwent two apheresis procedures. No large-volume leukapheresis was done. The median of peripheral blood processed was 10 and 15 l in GM and PM, respectively. No significant differences in terms of PM were observed in patients treated with DNR or MITOX or IDA (19.2% in the DNR group vs 30% in the MITOX group vs 25% in the IDA group were PM). The median percentage of CD34 premobilization chemotherapy was 0.08 (range 0.02– 0.19%) vs 0.02 (0.001–0.02%) in GM and PM, respectively; this translated into a median concentration of 6 106/l (range 4–10) vs 1 (range 0–5) in GM and PM, respectively (Po0.05). A correlation analysis showed that steady-state PB CD34 þ cells can reliably assess the CD34 þ cell yield in mobilized PB (Po0.05; r ¼ 0.77) (Figure 1). When grouped according to diagnosis, patients with ALL showed a higher baseline CD34 þ cell count than AML patients (7 vs 3 106/l in ALL and AML, respectively). In AML patients, no differences were found between the two groups (GM and PM), as regards the time from starting mobilization chemotherapy until apheresis (18 vs 19 days), the time from starting mobilization chemotherapy until recovery of neutrophils (17 vs 19 days) and the time between starting induction therapy and starting mobilization chemotherapy (48 vs 50 days); also, in ALL patients, no differences were found between the two groups (GM and PM), as regards the time from starting mobilization chemotherapy until apheresis (14 vs 15 days), the time from starting mobilization chemotherapy until recovery of neutrophils (13 vs 15 days), and the time between starting induction therapy and starting mobilization chemotherapy (48 vs 50 days). The median number of CD34 þ cells at the first day of apheresis Good mobilizers Poor mobilizers 77 (74.1%) 46 (69.7%) 31 (81.6%) 38 38 (76%) 39 (78%) 6 (4–10) 7.8 (1.2–50) 2.5 (0.4–7.8) 21 (80.8%) 15 (75%) 14 (70%) 5/77 (6.4%) 160 (40–1200) 10 (8–12) 1.2 27 (25.9%) 20 (30.3%) 7 (18.4%) 46 12 (24%) 15 (28%) 1 (0–5) 5.6 (1.8–43) 1.8 (0.3–7) 5 (19.2%) 5 (25%) 6 (30%) 25/27 (92.5%) 12 (5–28) 15 (10–18) 2 Po0.05 Po0.005 Po0.001 45 Leukapheresis product CD34+ cells × 106/Kg Table 2 40 35 30 25 20 15 10 5 0 0 2 4 6 8 10 Peripheral blood steady-state CD34+ × 10 12 6/L Figure 1 Correlation of steady-state PB to mobilized CD34 þ cell counts (r ¼ 0.77, Po0.05). was also higher in GM vs PM (160 vs 12 106/l) (Po0.001); the number of CD34 þ cells in the peripheral blood on the first day of apheresis was strongly correlated with the yields of CD34 in the relative harvest (r ¼ 0.81, Po0.001) (Figure 2). A value below 20 106/l CD34 was associated with an 85% probability of PM and a value above 60 106/l CD34 was associated with a 90% probability of GM. As regards FUO or clinically or microbiologically documented infection during the neutropenic phase after consolidation chemotherapy, we found that FUO or infection adversely affected mobilization (of the patients with FUO or infection, 25/30 or 83.3% were PM) (Po0.005). In the PM group with fever (25 patients), there were 18 FUO and seven microbiologically documented infections; in the GM group with fever (five patients), there were four FUO and one microbiologically documented infection. Bone Marrow Transplantation CD34 þ cells mobilization in acute leukemia D Pastore et al 1086 CD34 cells collected (106/Kg) 60 50 40 30 20 10 0 0 200 400 600 800 1000 1200 1400 CD34 cell count (× 106/L) on the PB at the day of collection CD34 þ cells collected kg, according to the CD34 þ cell counts in the peripheral blood on the day of collection (r ¼ 0.81, Po0.001). Figure 2 Discussion There are few available data concerning mobilization of PBSC in acute leukemia (AL) patients. We analyzed 152 PBSC collections in 104 AL patients in order to identify the possible predictive factors of the CD34 þ cells collection; all patients had received only one cycle of induction chemotherapy and one cycle of consolidation–mobilization chemotherapy. We have shown that, in the majority of patients with AL (74.1%), a target quantity of 2 106/kg could be collected from the peripheral blood following GCSF-supported consolidation chemotherapy; the threshold number of 2 106 CD34 þ cells/kg was chosen on the basis of previous studies demonstrating rapid and sustained engraftment following reinfusion of this amount.7–11 When consolidation–mobilization chemotherapy was started, the patients were in first cytological CR following one cycle of induction chemotherapy. The effect of patient age as a predictor of the PBSC collection content is not clear. Lower age was a significant factor in obtaining a larger number of CD34 þ cells in the collection of patients in one study,7 but age was not related to collection efficiency in other studies;17,23 we did not find any correlation between sex or age of the patients and the yields achieved. In terms of diagnosis, 20/66 (30.3%) AML patients and 7/38 (18.4%) ALL patients were poor mobilizers; the role of previous stem cell damage from cytotoxic drugs is the likely explanation,18,19,21,23 as these ALL patients had been less heavily pretreated during induction chemotherapy than AML patients. In our experience, patients with ALL showed a higher baseline CD34 þ cell count preconsolidation chemotherapy than AML patients; this difference in the yield of CD34 þ cells may be related to significant differences in the hemopoietic reserve and individual sensitivity of the hemopoietic progenitor cells to chemotherapy-related toxicity.17 Fruehauf et al 24 found that PBSC counts in Hodgkin and non-Hodgkin lymphoma, multiple myeloma and solid tumors during steady-state hemopoiesis enable estimation of the yield of mobilized Bone Marrow Transplantation PBSC after G-CSF-supported cytotoxic chemotherapy. In our experience in this group of 104 AL patients, a clear correlation was observed between the steady-state PB CD34 þ cell count and the outcome of mobilization; the median number of CD34 premobilization chemotherapy was higher in good than poor mobilizers (Po0.05). Highbaseline PB CD34 þ cells in AL patients predict a high stem cell yield after mobilization with chemotherapy and G-CSF, irrespective of diagnosis, age and type of chemotherapy. Other studies regarding lymphoma and solid tumor patients25–27 reported a strong correlation between the absolute cell number of circulating CD34 þ on the day of apheresis and the number of CD34 þ cells collected; we also found this correlation in our 104 AL patients (Po0.001). In our report, the presence of clinically or microbiologically documented fever or infection was associated with poor mobilization (Po0.005); inflammatory cytokines with their negative effect on the proliferation of stem cells may have a role in this poor mobilization.28–30 The number of prior cytotoxic chemotherapy cycles has been reported to adversely affect the yield of PBSC in lymphoma, myeloma and solid tumor patients,12–16 but Jowitt et al 21 showed that the number of induction courses received, and thus exposure to cytotoxic agents received, made no significant difference to the subsequent CFU-GM content in the peripheral blood in AL patients. In our series, all patients had received only one line induction-chemotherapy and one consolidation–mobilization chemotherapy before the PBSC collection. The timing of PBSC collection is therefore crucial and should be envisaged following efficient in vivo depletion of leukemic cells, but still before the hemopoietic reserve is impaired. We conclude that the CD34 cell count in the steady state, the absence of fever or infection and the CD34 þ cells in the peripheral blood on the day of apheresis are reliable predictors of the success of PBCS collection. High-baseline PB CD34 þ cells in AL patients achieving CR after one chemotherapy cycle may predict a high stem cell yield after the first consolidation therapy and G-CSF. The routine determination of baseline PB CD34 þ cell counts may identify patient groups at risk of a poor stem cell yield, who would thus qualify for enrolment in clinical trials on different mobilization regimens. Acknowledgements This work was supported by Ministero dell’Istruzione dell’Università e della Ricerca (MIUR); we thank Ms MVC Pragnell, BA, for language assistance in the preparation of the manuscript. References 1 Gratwohl A, Passweg J, Baldomero H et al. Blood marrow transplantation activity in Europe 1997: European Group for Blood Marrow Transplantation (EBMT). Bone Marrow Transplant 1999; 24: 231–245. 2 Korbling M, Fliedner TM, Holle R et al. Autologous blood stem cell (ABSCT) versus purged bone marrow transplantation CD34 þ cells mobilization in acute leukemia D Pastore et al 1087 3 4 5 6 7 8 9 10 11 12 13 14 15 (pABMT) in standard risk AML: influence of source and cell composition of the autograft on hematopoietic reconstitution and disease free survival. Bone Marrow Transplant 1991; 7: 343–349. Sanz MA, De la Rubia J, Sanz GF et al. Busulfan plus cyclophosphamide followed by autologous blood stem cell transplantation for patients with acute myeloblastic leukaemia in first complete remission: a report from a single institution. J Clin Oncol 1993; 11: 1661–1667. De la Rubia J, Sanz JF, Martin G et al. Autologous blood stem cell transplantation for acute myeloblastic leukaemia in first complete remission: intensification therapy before transplantation does not prolong disease-free survival. Haematologica 1999; 84: 125–132. To LB, Roberts MM, Haylock DN et al. Comparison of haematological recovery times and supportive care requirements of autologous recovery phase peripheral blood stem cell transplant, autologous bone marrow transplant and allogeneic bone marrow transplants. Bone Marrow Transplant 1992; 9: 277–284. Beyer J, Schwella N, Zingsem J et al. Hematopoietic rescue after high-dose chemotherapy using autologous peripheralblood stem cells or bone marrow: a randomised comparison. J Clin Oncol 1995; 13: 1328–1335. Besinger WI, Longin K, Appelbaum F et al. Peripheral blood stem cells (PBSCs) collected after recombinant granulocyte colony-stimulating factor (rhG-CSF): an analysis of factors correlating with the time of engraftment after transplantation. Br J Haematol 1994; 87: 825–831. Weaver CH, Hazelton B, Birch R et al. An analysis of engraftment kinetics as a function of the CD34 content of peripheral blood stem cell collections in 692 patients after the administration of myeloablative chemotherapy. Blood 1995; 86: 3961–3969. Kiss JE, Rybka WB, Winkelstein A et al. Relationship of CD34+ cell dose to early and late hematopoiesis following autologous peripheral blood stem cell transplantation. Bone Marrow Transplant 1997; 19: 303–310. Haas R, Witt B, Mohle R et al. Sustained long-term hematopoiesis after myeloablative therapy with peripheral blood progenitor cell support. Blood 1995; 85: 3754–3761. Ketterer N, Salles G, Raba M et al. High CD34(+) cell counts decrease hematologic toxicity of autologous peripheral blood progenitor cell transplantation. Blood 1998; 91: 3148–3155. Alegre A, Tomas JF, Martinez-Chamorro C et al. Comparison of peripheral blood progenitor cell mobilization in patients with multiple myeloma: high dose cyclophosphamide plus GM-CSF versus G-CSF alone. Bone Marrow Transplant 1997; 20: 211–217. Besinger W, Appelbaum F, Rowley S et al. Factors that influence collection and engraftment of autologous peripheral blood stem cells. J Clin Oncol 1995; 13: 2547–2555. Watts MJ, Sullivan AM, Jamieson E et al. Progenitor cell mobilization after low-dose cyclophosphamide and granulocyte colony-stimulating factor: an analysis of progenitor cell quantity and quality and factors predictive for these parameters in 101 pre-treated patients with malignant lymphoma. J Clin Oncol 1997; 15: 535–546. Moskowitz CH, Glasmann GR, Wuest D et al. Factors affecting mobilization of peripheral blood progenitor cells 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 in patients with lymphoma. Clin Cancer Res 1998; 4: 311–316. Sautois B, Fraipont V, Baudoux E et al. Peripheral blood progenitor cell collections in cancer patients: analysis of factors affecting the yields. Haematologica 1999; 84: 342–349. Dreger P, Kloss M, Petersen B et al. Autologous progenitor cell transplantation: prior exposure to stem cell-toxic drug determines yield and engraftment of peripheral blood progenitor cell but not of bone marrow grafts. Blood 1995; 86: 3970–3978. Kotasek D, Shepherd KM, Sage RE et al. Factors affecting blood stem collections following high-dose cyclophosphamide mobilization in lymphoma, myeloma and solid tumors. Bone Marrow Transplant 1992; 9: 11–17. Carral A, De La Rubia J, Martin G et al. Factors influencing the collection of peripheral blood stem cells in patients with acute myeloblastic leukemia and non-myeloid malignancies. Leukaemia Res 2003; 27: 5–12. Schelenk R, Dohner H, Pforsich M et al. Successful collection of peripheral blood progenitor cells in patients with acute myeloid leukaemia following early consolidation therapy with granulocyte colony-stimulating factor-supported highdose cytarabine and mitoxantrone. Br J Haematol 1997; 99: 386–393. Jowitt SN, Chang J, Morgenstern GR et al. Factors which affect the CFU-GM content of the peripheral blood haemopoietic progenitor cell harvests in patients with acute myeloid leukaemia. Br J Haematol 1998; 100: 668–694. Moretti S, Dabusti M, Castagnari B et al. Comparison of single and dual platform methodologies for the estimation of CD34+ hematopoietic progenitor cells: correlation with colony assay. Int J Biol Markers 2002; 17: 259–267. Drake M, Ranaghan L, Morris M et al. Analysis of the effect of prior therapy on progenitor cell yield: use of a chemotherapy scoring system. Br J Haematol 1997; 98: 745–749. Fruehauf S, Schmitt K, Veldwijk R et al. Peripheral blood progenitor cell (PBPC) counts during steady-state haemopoiesis enable the estimation of the yield of mobilized PBPC after granulocyte colony-stimulating factor supported cytotoxic chemotherapy: an update on 100 patients. Br J Haematol 1999; 105: 786–794. Diaz M, Sanchez-Garcia F, Lillo R et al. Large-volume leukapheresis in pediatric patients: pre-apheresis peripheral blood CD34+ cell count predicts progenitor cell yield. Haematologica 1999; 84: 32–35. Benjamin RJ, Linsley L, Fountain B et al. Preapheresis peripheral blood CD34+ mononuclear cell counts as a predictor of progenitor cell yield. Transfusion 1997; 37: 79–85. Elliot C, Samsom DM, Armitage S et al. When to harvest peripheral-blood stem cells after mobilization therapy: prediction of CD34-positive cell yield by preceding day CD34positive concentration in peripheral blood. J Clin Oncol 1996; 14: 970–973. Xiao W, Koizumi K, Nishio M et al. Tumor necrosis factoralpha inhibits generation of glycophorine A+ cells by CD34+ cells. Exp Hematol 2002; 30: 1238–1247. Carlo-Stella C, Tabilio A. Stem cell and stem cell transplantation. Haematologica 1996; 81: 573–587. Ogawa M. Differentiation and proliferation of hemopoietic stem cells. Blood 1993; 81: 2844–2853. Bone Marrow Transplantation