Evaluation of hematopoietic progenitors in hematopoietic progenitor cell transplants. CD34+ dose effect in marrow recovery. Retrospective analysis in 38 patients

Our main goal was to evaluate the CD34+ dose in patients undergoing haemotopoietic stem celltransplantation and its results in terms of recovery of neutrophile and platelet counts, transfusion requirements, days of fever, antibiotic requirements and length of hospital stay. We studied 38 consecutive patients with haematological malignancies transplanted at our Department, from Feb. 96 through Sept. 98. The CD34+ cell quantification technique was standardized, using a modification of the ISAGHE 96 protocol. Patients were sorted into three groups according to the CD34+ count administered: a) between 3 and 5 × 10⁶ cells/kg; b) between 5 and 10 × 10⁶ cells/kg; c) > 10 × 10⁶ CD34+ cells/kg. As a secondary end point, results were assessed according to the number of aphereses required to arrive at the target count of CD34+, separating those patients that required only 1 or 2 aphereses versus those requiring 3 or more. Finally, an analysis was made of the results of transplantation comparing the different sources of stem cells (PBSC versus PBSC + B.M.). The best results were obtained in the group with cells between 3 and 5 × 10⁶ CD34+. No statistically significant advantages were found in the group with cells over 5. The supra-optimal dose of more 10 x 10⁶ would yield no additional beneficial results, while they can imply a greater infusion of residual tumor cells. The number of aphereses had no impact on engraftment. Results obtained with PBSC transplants were better than those with BM+PBSC in terms of neutrophile and platelet recovery. The number of CD34+ cells remains the main element in stem cell transplantation to evaluate the haematopoietic recorery after engraft-ment. Minimum and optimum yields remain unclear. Centers should establish their own optimal dose based on local methodologies and outcomes, maximizing costs and benefits.     

Prognostic Factors of Peripheral Blood Stem Cell Mobilization with Cyclophosphamide and Filgrastim (r-metHuG-CSF): The CD34+ Cell Dose Positively Affects the Time to Hematopoietic Recovery and Supportive Requirements after High-Dose Chemotherapy

To prospectively analyze factors that influence peripheral blood stem cell (PBSC) collection and hematopoietic recovery after high-dose chemotherapy (HDC), 39 patients received cyclophosphamide 4 g/m² and rHuG-CSF (Filgrastim) 5 μg/kg/day. Leukapheresis was started when CD34⁺ cells/mL were > 5 × 10³. A minimum of 2 × 10⁶ CD34⁺ cells/kg was collected. Median steady-state bone marrow CD34⁺ cell percentage was 0.8% (range, 0.1 to 6). Thirtytwo patients received HDC with autologous PBSC transplantation plus Filgrastim.

A median of 2 (range, 0 to 6) leukapheresis per patient were performed and a median of 6.3 × 10⁶ CD34⁺ cells/kg (range, 0 to 44.4) collected; four patients failed to mobilize CD34⁺ cells. The number of cycles of prior chemotherapy had an inverse correlation with the number CD34⁺ cells/kg collected (r =—0.38; p < 0.005). Patients with <7 cycles had a higher predictability for onset of leukapheresis than patients with ³7 (93% versus 50%; p < 0.005). The four patients who failed to mobilize had received ≥7 cycles. The number of CD34⁺ cells/kg infused after HDC had an inverse correlation with days to recovery to 0.5 × 10⁹ neutrophils/L and 20 X 10⁹ platelets/L (r =—0.68 and—0.56; p < 0.005). The effect of these factors on mobilization and hematopoietic recovery were confirmed by multivariate analysis. Requirements for supportive measures were significantly lower in patients given a higher dose of CD34⁺ cells/kg.

Therefore, PBSC collection should be planned early in the course of chemotherapy. Larger number of CD34⁺ cells/kg determined a more rapid hematopoietic recovery and a decrease of required supportive measures.     

Comparison of marrow and blood cell yields from the same donors in a double-blind, randomized study of allogeneic marrow vs blood stem cell transplantation

Forty healthy adult donors underwent marrow (BM) as well as peripheral blood (PBSC) stem cell collections for their HLA-identical adult siblings with hematologic malignancies. BM was harvested on day 1 (target 3 x 108 nucleated cells/kg, 10 microg/kg lenograstim (glycosylated G-CSF) administered on days 2-6, and a single leukapheresis performed on day 6. The blood volume processed was the higher of 200% donor blood volume or 10 liters. The total nucleated cell (TNC) yields from PBSC were 1.1- to 4.3-fold higher than BM (median 7.0 vs 3.1 x 10(8)/kg, P < 0.0001). Although BM contained a higher proportion of CD34+cells (1.3% vs 0.7%, P < 0. 0001) and a comparable proportion of CD3+ cells (median 29% vs 26%, P = 0.4), the absolute numbers of CD34+ and CD3+ cells and their subsets were several times higher in PBSC. There was a poor correlation between BM and PBSC CD34 and TNC numbers, but a significant correlation between BM and PBSC CD3 numbers. Only five of 40 BM harvests contained >/=2 x 10(6) CD34+ cells/kg compared with 35 of 40 PBSC harvests (P < 0.0001). We conclude that the numbers of progenitor and immunocompetent cells in PBSC are several times higher than in BM. It is possible to collect adequate numbers of progenitor cells from blood after lenograstim stimulation more frequently than from marrow, and donors yielding low quantities of progenitor cells from BM usually deliver better quantities from PBSC. Bone Marrow Transplantation (2000) 25, 501-505.     

Positive selection of CD34+ peripheral blood progenitor cells in patients with low-grade lymphoid malignancies and bone marrow involment

Purpose. 16 patients with low-grade lymphoid malignancies and bone marrow involment were transplanted with selected CD34 positive Peripheral Blood Progenitor Cell (PBSC) prepared from autologous aphereses. Patient and methods. All but one patients were mobilized with a combination of chemotherapy (including high-dose cyclophosphamide and VP16 or adriamycin, aracytin with cysplatyl) and recombinant human Granulocyte Colony-Stimulating Factor (rhG-CSF).Results. A median of 3 (range, 1 to 9) aphereses yielded 15.35 × 10⁶ CD34+ cells/kg (range, 4.45 to 70.88). A median of 5.01 × 10⁶ adsorbed CD34+ cells/kg (range 2.01 to 24.13) was obtained after selection (median purity: 86%; range, 59-99%). The CD34 PBSC were infused one day after either one of two conditioning regimens: 11 patients received the association of cyclophosphamide (120 mg/kg) and TBI (8Gy), and 5 patients received the BEAM regimen. No recombinant hematopoietic growth factor was used after cell reinfusion. Median days to 0.5 × 10⁹/l neutrophils and 50 × 10⁹/l platelets were 13 (range, 9 to 18) and 16 (range, 11 to 35), respectively. The median number of red blood cell (RBC) unit transfusions was 4 (range, 0 to 10). The median number of platelet transfusions was 3.5 (range, 0 to 8). No individual received backup PBSC, nor required platelet transfusion beyond 3 months post-transplant. Conclusion. This study confirms the feasability of using blood CD34 cells to support hematopoietic recovery after myelo-suppressive or myelo-ablative regimens, in patients with low-grade NHL.This work was supported by the Institut Paoli-Calmettes and a special grant from Amgen.     

Autografting with blood progenitor cells: predictive value of preapheresis blood cell counts on progenitor cell harvest and correlation of the reinfused cell dose with hematopoietic reconstitution

One hundred and nine patients suffering from various malignancies underwent 285 apheresis procedures for PBPC collection. A median of two leukaphereses (range: 2–5) resulted in median numbers of 4.6×10 ⁸ MNC/kg, 14.1×10 ⁴ CFU-GM/kg, and 6.0×10 ⁶ CD34+ cells/kg. Preleukapheresis peripheral blood CD34+ cells correlated significantly with collected CD34+ cells/kg ( r=0.94; p<0.0001) and with CFU-GM/kg ( r=0.52; p<0.0001). A value >4×10 ⁴ CD34+ cells/ml was highly predictive for a collection yield >2.5×10 ⁶ CD34+ cells/kg harvested by a single leukapheresis. Sixty patients were evaluated for hematologic reconstitution and engrafted in a median time of 10 days for WBC >1.0×10 ⁹/l (range: 7–21 days), 10 days for ANC >0.5×10 ⁹/l (7–20) and 11 days for PLT >20×10 ⁹/l (7–62). Reinfused CD34+ cells/kg correlated significantly with hematologic engraftment ( r=0.44–0.52 and p<0.006–0.001) as well as CFU-GM/kg ( r=0.36–0.44 and p<0.007–0.001). A progenitor cell dose >2.5×10 ⁶ CD34+ cells/kg or >8.0×10 ⁴ CFUGM/kg led to a significantly faster recovery for WBC, ANC, and PLT when compared with patients receiving <2.5×10 ⁶ CD34+ cells/kg or <8.0×10 ⁴ CFU-GM/kg. We conclude that rapid hematopoietic engraftment after high-dose therapy and PBPC reinfusion correlates well with a progenitor cell dose >2.5×10 ⁶ CD34+ cells/kg or >8.0×10 ⁴ CFU-GM/kg, and that above a preleukapheresis threshold of 4×10 ⁴ CD34+ cells/ml a PBPC autograft containing >2.5×10 ⁶ CD34+ cells/kg can be collected by a single leukapheresis. We suggest that patients recovering from myelosuppression should be monitored for CD34+ cells in serial blood samples to determine the course of circulating hematopoietic progenitor cells. This issue will help to define the optimal time point to start apheresis and to predict a PBPC autograft harvested by a single leukapheresis, which will lead to rapid and stable hematopoietic reconstitution following transplantation.     

An antecedent diagnosis of refractory anemia with excess blasts has no influence on mobilization of peripheral blood stem cells and hematopoietic recovery after autologous stem cell transplantation in acute myeloid leukemia

Several studies have reported data on factors influencing mobilization of peripheral blood stem cells (PBSC) in non-myeloid malignancies. On the contrary, data from patients with acute myeloid leukemia (AML) are very limited, in particular, as the impact of an antecedent diagnosis of refractory anemia with excess blasts (RAEB) on mobilization of PBSCs as well as hematopoietic recovery after autologous stem cell transplantation (ASCT) is concerned. We retrospectively analyzed a cohort of 150 consecutive AML patients in first complete remission in order to make a comparison between patients with de novo AML and secondary AML (s-AML) in terms of CD34 positive (CD34+) cells mobilization and number of leukapheresis needed to collect at least one single stem cell graft. Data concerning hematopoietic recovery after ASCT were also compared. The successful mobilization rate (>2 x 10(6) CD34+ cells/kg) was comparable between de novo AML patients (87%) and those with s-AML (76%), P:0.21. No statistically significant difference was found in terms of either median number of CD34+ cells collected (P:0.44) or CD34+ cells peak in peripheral blood (P:0.28). Both groups of patients needed a median of two apheresis (P:0.45) and no difference was found on the median number of CD34+ cells collected per single apheresis (P:0.59). Finally, neutrophil and platelet recovery after ASCT were comparable between the two groups. An antecedent diagnosis of RAEB has no impact on mobilization and collection of PBSCs in AML as well as on hematopoietic recovery after ASCT.     

Circulating Stem Cell Collection in Lymphoma and Myeloma after Mobilization with Cyclophosphamide and Granulocyte Colony-Stimulating Factor for Autologous Transplantation

We report the results of 72 leukapheresis procedures performed for autologous peripheral blood stem cell collection in 18 patients with lymphoma and myeloma, after combined mobilization with cyclophosphamide and granulocyte colony-stimulating factor (G-CSF). The numbers of mononuclear cells (MNCs), CD34+ cells and granulocyte-macrophage colony-forming units (CFU-GM) either in the peripheral circulation (preleukapheresis sample) or in the product obtained from leukapheresis (leukapheresis sample) were evaluated. A highly superior proportion of CD34+ cells (14-fold) and CFU-GM (5-fold) resulted from the mobilization therapy. CFU-GM and CD34+ cells were highly enriched with respect to all MNCs (relative recoveries: 2.13, range 0.3–41, and 1.08, range 0.2–8.5, respectively) due to an additional mobilization effect by the leukapheresis procedure. Also, a relatively strong linear correlation between the three different parameters was found in the leukapheresis product (CD34+:CFU-GM, r = 0.81; MNCs:CD34, r = 0.69; MNCs:CFU-GM, r = 0.75; CFU-GM:CD34+, and MNCs, r = 0.85). Our data suggest that the number of MNCs and CD34+ cells obtained after combined mobilization with cyclophosphamide and G-CSF can be used as predictor of the number of granulomonocytic progenitors.     

Bone Marrow Transplantation: Prognostic Factors of Peripheral Blood Stem Cell Mobilization with Cyclophosphamide and Filgrastim (r-metHuG-CSF): The CD34+ Cell Dose Positively Affects the Time to Hematopoietic Recovery and Supportive Requirements after High-Dose Chemotherapy

To prospectively analyze factors that influence peripheral blood stem cell (PBSC) collection and hematopoietic recovery after high-dose chemotherapy (HDC), 39 patients received cyclophosphamide 4 g/m(2) and rHuG-CSF (Filgrastim) 5 &mgr;g/kg/day. Leukapheresis was started when CD34(+) cells/mL were > 5 x 10(3). A minimum of 2 x 10(6) CD34(+) cells/kg was collected. Median steady-state bone marrow CD34(+) cell percentage was 0.8% (range, 0.1 to 6). Thirty-two patients received HDC with autologous PBSC transplantation plus Filgrastim. A median of 2 (range, 0 to 6) leukapheresis per patient were performed and a median of 6.3 x 10(6) CD34(+) cells/kg (range, 0 to 44.4) collected; four patients failed to mobilize CD34(+) cells. The number of cycles of prior chemotherapy had an inverse correlation with the number CD34(+) cells/kg collected (r = -0.38; p < 0.005). Patients with <7 cycles had a higher predictability for onset of leukapheresis than patients with (3) 7 (93% versus 50%; p < 0.005). The four patients who failed to mobilize had received >/=7 cycles. The number of CD34(+) cells/kg infused after HDC had an inverse correlation with days to recovery to 0.5 x 10(9) neutrophils/L and 20 x 10(9) platelets/L (r = -0.68 and -0.56; p < 0.005). The effect of these factors on mobilization and hematopoietic recovery were confirmed by multivariate analysis. Requirements for supportive measures were significantly lower in patients given a higher dose of CD34(+) cells/kg. Therefore, PBSC collection should be planned early in the course of chemotherapy. Larger number of CD34(+) cells/kg determined a more rapid hematopoietic recovery and a decrease of required supportive measures.     

Effect of CD34 cell dose on hematopoietic reconstitution and outcome in 508 patients with multiple myeloma undergoing autologous peripheral blood stem cell transplantation

BACKGROUND: We analyzed the hematopoietic reconstitution and outcome of 508 patients with multiple myeloma (MM) with respect to the number of CD34+ cells reinfused at our center. PATIENTS AND METHODS: Each cohort of 390 patients (unselected CD34+ cell transplant) and 118 patients (CD34+ selected transplant) was divided into four subgroups. Among the 390 transplantations, 86 patients received a high dose (HD-) of > or =6.50 x 10(6) unselected CD34+ cells/kg, 116 patients a low dose (LD-) of <3.00 x 10(6) CD34+ cells/kg. Among the patients treated with CD34+ selected PBSC, 34 received > or =6.50 x 10(6) CD34+ cells/kg (HD+) and 16 <3.00 x 10(6) CD34+ cells/kg (LD+). RESULTS: HD- patients experienced a reduced median time to leukocyte (13 d vs. 14 d) (P < 0.001) and platelet reconstitution >20 x 10(9)/L (10 d vs. 12 d) (P < 0.001). Similarly, HD+ showed a reduced median time to leukocyte (12 d vs. 15 d) (P < 0.001) and platelet recovery >20 x 10(9)/L (10 d vs. 11 d) (P = 0.058). CD34+ cell-dose was significant for long-term platelet recovery at day 360 (unselected transplant P = 0.015, selected transplant P = 0.023). Number of transplanted CD34+ cells had no significant impact on transplant related mortality, overall survival or CR/PR rates within 100 d. In terms of supportive care the differences of high-/low-dose grafts were minimal. CONCLUSIONS: These results confirm that high doses of CD34+ PBSC shorten hematopoietic reconstitution and reduce hospitalization. Nevertheless secure engraftment results from transplantation of 2.00-3.00 x 10(6) CD34+ cells/kg. As 60% of our pretreated patients are able to collect > or =5.00 x 10(6) CD34+ cells/kg within a single leukapheresis, division into two or more freezing bags allows safe tandem transplantation in the majority of MM patients.     

Collection efficiencies of CD34+ progenitor cells and mononuclear cells in leukapheresis products quantified by flow cytometry and calculated on the basis of a new formula

BACKGROUND AND OBJECTIVES: Optimal mobilization and harvest of hematopoietic progenitors are essential for peripheral blood stem cell transplantation after myeloablative high-dose chemotherapy. Conflicting data have been published concerning the most useful, cost-effective collection strategy which is also convenient for patients. MATERIALS AND METHODS: A total of 66 leukaphereses in 20 patients were retrospectively evaluated. We assessed the predictive value of the number of white blood cells, mononuclear cells (MNCs) and CD34+ cells in peripheral blood for the yield of CD34+ cells in leukapheresis products. The concentrations of MNCs and CD34+ cells were quantified simultaneously by a flow cytometric procedure using fluorescent microparticles. Their collection efficiencies were calculated based on a newly developed formula. RESULTS: The collected hematopoietic progenitor concentration could be predicted only by the number of peripheral blood CD34+ cells prior to apheresis (r = 0.902; p<0.01). Furthermore, the mobilization of at least 30 CD34+ cells/microl peripheral blood was a good predictor that a single leukapheresis would yield a minimum of 2.0x10(6) CD34+ cells/kg body weight. The collection efficiencies calculated by the new formula were 55.2+/-10.7% and 57.7+/-11.2% for MNCs and CD34+ cells, respectively. CONCLUSION: The precise quantification of MNCs and CD34+ cells by a direct flow cytometric assay, as well as the new formula to determine the collection efficiencies, has an impact on optimizing high-quality stem cell products.     

Estimation of the Progenitor Cell Yield in a Leukapheresis Product by Previous Measurement of CD34+ Cells in the Peripheral Blood

To assess whether measurement of CD34+ cells in the peripheral blood allows one to estimate the progenitor cell yields of subsequent leukapheresis procedures, 733 corresponding blood and leukapheresis samples were analyzed. Peripheral blood progenitor cells of cancer patients were mobilized with hematopoietic growth factors alone or postchemotherapy, and harvested processing 10 liters of blood for each leukapheresis product. The CD34+ cell count (CD34+ cells/μl blood) correlated most closely with the progenitor cell yield in the corresponding leukapheresis product (CD34+ cells/kg bodyweight, r = 0.80), while the proportion of circulating CD34+ cells to the white blood and mononuclear cells predicted the yield less reliably (r = 0.74 and r = 0.60). The CD34+ cell yield was independent of the white blood count (r = 0.04), whereas a weak correlation was found between the mononuclear cell count and the number of CD34+ cells/kg collected (r = 0.42). It was unlikely to obtain the threshold quantity of 2.5 × 10⁶ CD34+ cells/kg required for rapid engraftment when counts below 10 CD34+ cells/μl blood were detected. At levels between 10 and 30 CD34+ cells/μl sufficient autografts could be harvested, whereas 30–100 CD34+ cells/μl were required to achieve this by a single leukapheresis. A surplus of CD34+ cells was likely above 100 CD34+ cells/μl which could be useful for progenitor cell enrichment techniques. The correlation between the CD34+ cell count and progenitor cell yield was independent of the mobilizing regimen and whether leukaphereses had been performed previously. In conclusion, the number of CD34+ cells/μl blood allows a reliable prediction of the CD34+ progenitor cell yield in subsequent leukapheresis procedures. However, rare cases of unexpectedly sufficient progenitor cell yields may be observed even at CD34+ cell levels below detection limit.     

Stem cell mobilization in resistant or relapsed lymphoma: superior yield of progenitor cells following a salvage regimen comprising ifosphamide, etoposide and epirubicin compared to intermediate-dose cyclophosphamide

We analysed the factors influencing the efficacy of peripheral blood stem cell (PBSC) collection in patients with lymphoma. Sixty-six patients underwent initial PBSC collection following mobilization with chemotherapy plus recombinant granulocyte colony-stimulating factor (300 μg/d). Patients were mobilized with one of two chemotherapy regimens, either cyclophophamide (3 g/m² or 4 g/m²) (n=50) or ifosphamide, etoposide and epirubicin (IVE; n=16). The target of collecting >2.0×10⁶ CD34⁺ cells/kg was achieved in 43/66 (65%) patients with a median of two apheresis procedures. The IVE plus G-CSF mobilization regimen gave a significantly higher median yield of CD34⁺ cells (8.62 × 10⁶/kg) compared with cyclophosphamide plus G-CSF (3.59 × 10⁶/kg) (P=0.045). The median yield of CD34⁺ cells per leukapheresis was almost twice as high in patients receiving IVE (1.94 × 10⁶/kg) compared to cyclophosphamide (1.03 ×10⁶/kg) (P= 0.035). In a univariate analysis of the factors affecting mobilization, the subtype of lymphoma (high-grade NHL) and the mobilization regimen were the only factors associated with high CD34⁺ cell yield. However, in a multivariate analysis of factors affecting mobilization including age, lymphoma subtype, previous chemotherapy and radiotherapy, only the use of the IVE protocol was predictive of a high yield of CD34⁺ cells. In 13 patients undergoing a second mobilization procedure the use of IVE was associated with a significantly higher yield of CD34⁺ cells compared to cyclophosphamide; three patients who failed cyclophosphamide plus G-CSF mobilization were able to proceed to transplantation following success-ful mobilization with IVE + G-CSF. These results demon-strate that IVE is a highly effective mobilization regimen which is superior to cyclophophamide and has the benefit of being effective salvage therapy for lymphoma patients.     

Automated collection of peripheral blood stem cells with the COBE spectra for autotransplantation

BACKGROUND: A convenient, effective and safe peripheral blood stem cell (PBSC) apheresis procedure is desirable to cope with the increasing requirements for PBSC collections. We performed PBSC harvesting with the novel COBE Spectra AutoPBSC(TM) system using the default software configuration recommended by the manufacturer. We analyzed collection parameters and clinical efficiency of harvested autografts following high-dose chemotherapy (HDCT). PATIENTS AND METHODS: Eighty-one patients underwent 102 harvests after standard chemotherapy plus filgrastim (5-10 microg/kg/day) to obtain a target of >/=2.5 x 10(6) CD34+ cells/kg for autologous blood stem cell transplantation. Conventional-volume leukaphereses (median: 11 liters) were performed using the manufacturer's standard software default regarding inlet flow, harvest/chase volume (3/7 ml) and number of collection cycles. The ratio of ACD-A to whole blood was initially set at 1:12 (56 collections), later at 1:10 (46 aphereses). RESULTS: With respect to preapheresis counts of 93 (9-876) CD34+ cells/microl, 69 patients (85.2%) achieved >/=2.5 x 10(6) CD34+ cells/kg by the first apheresis. PBSC products contained medians of 5.0 x 10(6) (0.7-77.3) CD34+ cells/kg and 13.8 x 10(4) (2.3-105.0) CFU-GM/kg. A preapheresis count of >/=40 CD34+ cells/microl predicted a single-apheresis yield of >/=2.5 x 10(6) CD34+ cells/kg. Apheresis products showed a high mononuclear cell (MNC) purity of >/=89%. The median overall collection efficiency of CD34+ cells (CD34-CE) was 42.6% (12.2-87.4). The CD34-CE decreased significantly with increasing numbers of circulating CD34+ cells: 52.5% at CD34+ cells <40/microl versus 41.0% at CD34+ cells >/=40/microl (p 0.5 x 10(3)/microl, 10 (8-13) days for WBC >1.0 x 10(3)/microl and 11 (8-17) days for platelets >20 x 10(3)/microl. CONCLUSIONS: As a result of efficient PBSC mobilization, a single conventional-volume leukapheresis with the COBE Spectra AutoPBSC system resulted in hematopoietic autografts with >/=2.5 x 10(6) CD34+ cells/kg in 85% of patients. Following the standard PBSC apheresis recommendations of the manufacturer, the AutoPBSC system assures PBSC products with a high MNC purity and a moderate CD34-CE that declines significantly at increasing levels of circulating CD34+ cells. Leukaphereses performed at an ACD-A to whole blood ratio of 1:10 should run without coagulation problems.     

Addendum

A recent randomized multicentric French study has shown that intensification with stem cell rescue improves the response rate and progression-free survival in multiple myeloma. Transplantation with primed peripheral blood stem cells (PBSC) displays a faster hematological recovery, especially for platelets, as compared with a bone marrow stem cell graft. In multiple myeloma, the optimal mobilization method for PBSC is unknown. The present study compares mobilization with cyclophosphamide 4 g/m² + G-CSF 5 μg/kg versus G-CSF 5 μg/kg alone versus G-CSF 10 μg/kg alone in two cases of multiple myeloma, using an intrapatient controlled evaluation of the amount of CD34-positive cells obtained during each leukapheresis. In both cases, the highest CD34-positive cells yield was obtained with G-CSF at 10 μg/kg. Despite the low number of cases, this method, devoid of life-threatening toxicity, might be of greatest interest in multiple myeloma. © 1994 Wiley-Liss, Inc.     

Blood stem cell collection using chemotherapy with or without systematic G-CSF: experience in 52 patients with multiple myeloma.

Harvesting of peripheral blood stem cells (PBSCs) following chemotherapy and G-CSF administration is currently performed for hematological therapies. However, a procedure based on the use of a large quantity of G-CSF is relatively costly. Therefore, we retrospectively compared the effects of two PBSC mobilization procedures in a population with recently diagnosed multiple myeloma. The first procedure consisted of chemotherapy and systematic G-CSF administration (group 1: 24 patients). The second consisted of chemotherapy alone, G-CSF having been administered only in the case of failure of PBSC mobilization or delayed white blood cell (WBC) recovery (group 2: 28 patients). Leukapheresis was performed when WBC recovery reached 1 x 10(9)/l if the peripheral blood CD34+ cell count was over 10/microl. Leukapheresis was maintained until a total of 2.5 x 10(6) CD34+ cells/kg was harvested. A significant difference was observed between the two groups only in regard to the median period of WBC recovery (delayed for group 2) and the number of CD34+ cells/kg collected on the first leukapheresis (higher for group 1) but not to the proportion of patients with failure of PBSC collection. Ten group 2 patients, who had insufficient CD34+ cells after WBC recovery or delayed WBC recovery, received G-CSF which resulted in sufficient PBSC harvesting in nine. To obtain a sufficient CD34+ cell level, the patients without systematic G-CSF administration had more leukaphereses (2.1 vs 1.5) but the mean consumption of G-CSF per patient was eight times less than in the other group. Nonsystematic use of G-CSF before WBC recovery or preferentially its introduction just after, could be an interesting economical alternative in PBSC mobilization but should be assessed by a prospective controlled study of cost/efficacy.     

A randomized trial of assessment of efficacy of leukapheresis volumes, 8 liters vs 12 liters

It is logical to expect that large-volume leukapheresis may be able to collect adequate numbers of PBSC with fewer procedures. To date, there is no agreement on the optimal volume of leukapheresis. Therefore, in this study we compared 8 l volume with 12 l and assessed whether a 50% increase in the blood volume processed would decrease the number of leukaphereses each patient needed to collect > or =2.5 x 10(6) CD34(+) cells/kg in normal mobilizers. PBSC mobilization was done with cyclophosphamide etoposide followed by rhG-CSF in all patients. Forty patients were randomized to undergo 8 l leukaphereses (n = 20 patients) or 12 l leukaphereses (n = 20). The median numbers of leukaphereses required in order to collect > or =2.5 x 10(6) CD34(+) cells/kg in patients processed with 8 l and 12 l were 1 (range 1-5) and 1 (1-4), respectively (P = 0.50). The median number of total nucleated cells (TNC) collected per patient was greater for the 12 l group (7.47 x 10(8)/kg vs 3.90 x 10(8)/kg, P < 0.001), as was the median number of total mononuclear cells (TMNC) (4.26 x 10(8)/kg vs 2.16 x 10(8)/kg, P < 0.001), whereas there was no difference between the two groups for the median number of CD34(+)cells collected per patient (8.94 x 10(6)/kg vs 8.60 x 10(6)/kg, P = 0.85). The TNCs and TMNCs collected per leukapheresis were again greater for the 12 l group (3.64 x 10(8)/kg vs 1.91 x 10(8)/kg, P = 0.001 and 2.17 x 10(8)/kg vs 0.88 x 10(8)/kg, P < 0.001), whereas there was no difference between the two groups for the median number of CD34(+) cells collected per leukapheresis (3.98 x 10(6)/kg vs 3.26 x 10(6)/kg, P = 0.90). This study showed that there is no difference between 8 l and 12 l volumes in regard to collected CD34(+) cells/kg and also the use of a 12 l leukapheresis volume did not decrease the number of leukaphereses performed compared with a 8 l leukapheresis volume. In fact, the use of the larger leukapheresis volume had the disadvantage of adding 60 min to the time the patient was on the machine.     

Successful peripheral blood stem cell mobilization using pegfilgrastim in allogeneic stem cell transplantation

Pegfilgrastim is produced by binding a 20,000-dalton polyethylene glycol molecule to granulocyte colony-stimulating factor (G-CSF), increasing the mass of the compound, and resulting in a longer-lasting form of G-CSF. This makes it more convenient to use pegfilgrastim as a single-day injection. This study was a prospective phase II single-center trial. Fifteen normal related donors received pegfilgrastim 12 mg subcutaneously to mobilize peripheral blood stem cells (PBSC) for allogeneic stem cell transplantation. Leukapheresis was planned to start 3 days after injection. All harvests were successful. Median number of leukapheresis was 2 days (range 1–3 days). There were 7/15 donors who only required single leukapheresis. The maximum concentration of white blood cells (WBC) and circulating CD34 cells occurred 3 days after pegfilgrastim injection (WBC: median 62,200/μl; CD34: median 69.76/μl). The median yield of CD34 cells was 6.78 × 10⁶/kg recipient weight. The median CD3 cells was 1.89 × 10⁸/kg recipient weight. The main adverse events were bone pain and headache. Median neutrophil and platelet engraftments in the recipients occurred on day 12 and day 13, respectively, after transplantation. PBSC mobilization with single-day injection of pegfilgrastim in normal donor is feasible. Further comparisons of this protocol to standard G-CSF for allogeneic stem cell mobilization should be conducted in future.     

Successful hematologic reconstitution using CD34+ cells positively selected from cryopreserved autologous peripheral blood stem cells in a patient with malignant lymphoma

Clinical use of CD34+ cells positively selected from cryopreserved peripheral blood stem cells (PBSC) has been limited, and there have been only a few reports of this procedure, mainly because clump formation decreases the proportion of CD34+ cells that can be recovered. A 49-year-old Japanese woman with non-Hodgkin's lymphoma (NHL) (follicular mixed, B cell, stage IVA) was treated with seven cycles of conventional chemotherapy and achieved partial remission. During hematopoietic recovery after the seventh course of chemotherapy, PBSC were harvested by continuous leukapheresis and cryopreserved. However, clonal rearrangement of the immunoglobulin heavy chain gene was detected in the PBSC by Southern blot analysis. After high-dose chemotherapy, CD34+ cells were positively immunoselected from the cryopreserved PBSC and infused into the patient at 1.97 x 10(6)/kg. The overall purity and recovery rate of the CD34+ cells were 72.2% and 65.0%, respectively. There were no severe adverse effects after PBSC transplantation, and the time required for recovery of neutrophils to over 0. 5 x 10(9)/l and platelets to over 50 x 10(9)/l was 11 and 21 days, respectively. Transplantation of CD34+ cells positively selected from cryopreserved PBSC provides engraftment ability similar to that of unmanipulated PBSC.     

G-CSF-mobilized peripheral blood progenitor cells for allogeneic transplantation: safety,kinetics of mobilization,and composition of the graft

Allogeneic transplantation of peripheral blood progenitor cells (PBPC) markes the general anaesthesia of the donor unnecessary and may result in more rapid engraftment and faster recovery of the immune system. We have studied G-CSF-mediated PBPC mobilization in healthy donors and analysed the cellular composition of the resulting PBPC grafts. PBPC grafts were obtained from nine healthy donors (18-67 years old) for allogeneic or syngeneic transplantation. Six donors received 10 μg/kg G-CSF per day, the others 5-6 μg/kg. Mobilization and harvesting were well tolerated except for moderate bone pain which occurred in all donors primed with 10 μg/kg. With 10 μg/kg, a 31-fold (9-62) enrichment of circulating CD34⁺ cells was observed with peak values constantly occurring on day 5 after the start of G-CSF administration. Starting harvest on day 5, one to three collections on consecutive days yielded 5.5 x 10⁶/kg (0.9-10.7) CD34⁺ cells, 219 x 10⁶/kg (106–314) T cells, and 34 x 10⁶/kg (23–67) NK cells per 10 litres leukapheresis volume. Altogether, PBPC grafts contained 3 times more CD34⁺ cells, 7 times more T cells, and 20 times more NK cells than five allogeneic marrow grafts that were analysed for comparison. The yield of CD34⁺ cells per 10 litres apheresis volume as well as the height of the CD34⁺ peak in peripheral blood were inversely correlated to the age of the donor. In the donors primed with 5–6μg/kg G-CSF the increase of circulating CD34⁺ cells (4–7-fold enrichment) and the CD34⁺ cell yield per 10 litres leukapheresis volume (1 x 10⁶/kg [0.8-2-2]) was much smaller compared with the 10μg/kg group. In conclusion, sufficient amounts of PBPC capable of restoring haemopoiesis in allogeneic recipients can be mobilized safely by administration of G-CSF (10 μg/kg s.c. for 5 d) in healthy donors, and harvested with one or two leukapheresis procedures. Whether the large numbers of T-cells and NK cells that are contained in the collection products may influence graft-versus-host and graft-versus-leukaemia reactivities of PBPC grafts remains to be determined.     

Single Dose Preemptive Plerixafor for Stem Cell Mobilization for ASCT After Lenalidomide Based Therapy in Multiple Myeloma: Impact in Resource Limited Setting

Peripheral blood stem cell mobilization with cytokines for autologous stem cell transplant in multiple myeloma is adversely affected by initial induction therapy consisting of either Lenalidomide or cytotoxic drugs, with failure rates of up to 45%. The use of Plerixafor with G-CSF for PBSC mobilisation significantly improves the chances of a successful mobilization. Plerixafor is a costly therapy and increases the overall costs of ASCT which can affect the number of patients being taken up for ASCT in resource limited settings. We prospectively studied the impact of single dose preemptive Plerixafor for PBSC mobilization in patients with prior Lenalidomide exposure. 26 patients who had received Lenalidomide based induction protocol underwent PBSC mobilisation during the study period with G-CSF 10 μg/kg/day SC for 4 days and single dose preemptive Plerixafor 240 μg/kg SC stat 11 h before the scheduled PB stem cell harvest on D5, based on a D4 PB CD34+ counts of <20/μL. A median of 07 cycles of Lenalidomide based combination therapy was used for induction therapy prior to ASCT. 84% patients underwent successful mobilization with one sitting of stem cell harvest post a single dose of Inj Plerixafor. 7.6% patients failed to mobilise the predefined minimum cell dose of CD34 and could not be taken up for ASCT. The median CD34% of the harvest bag sample was 0.33% (0.1–0.97%). Injection site erythema (34%), paresthesia’s (34%) and nausea (30%) were the commonest adverse events reported post Inj Plerixafor. We did a real-world cost analysis for a resource limited setting for PBSC mobilization and found significant cost savings for the preemptive Plerixafor group.