Autologous transplantation of granulocyte colony-stimulating factor-primed bone marrow is effective in supporting myeloablative chemotherapy in patients with hematologic malignancies and poor peripheral blood stem cell mobilization

Factors that predict delayed platelet recovery after autologous stem cell transplantation for lymphoma or myeloma

The amount of infused CD34⁺ cells has been reported to be the strongest predictor of platelet recovery after autologous stem cell transplantation (ASCT). However, the timing of platelet recovery varies widely among patients even after the infusion of similar amounts of CD34⁺ cells. Therefore, we retrospectively assessed 99 patients who underwent their first ASCT for lymphoma or myeloma at our center. Thirteen patients (13%) did not achieve platelet engraftment, defined as a platelet count of at least 2.0 × 10⁴/μL without transfusion, at day 28 after transplantation, whereas 58 of 60 patients (97%) who received at least 2.0 × 10⁶/kg CD34⁺ cells achieved platelet engraftment within 28 days. Multivariate analysis identified the following significant risk factors for delayed platelet recovery: hemoglobin level and platelet count before stem cell harvest, body temperature of > 39 °C within 5 days after ASCT, and infusion of a small amount (< 2.0 × 10⁶/kg) of CD34⁺ cells. In a subgroup analysis of 39 patients infused with < 2.0 × 10⁶/kg CD34⁺ cells, a need for repeated apheresis for stem cell harvest and a body temperature of > 39 °C within 5 days after ASCT were identified as independent factors for delayed platelet recovery. In summary, platelet recovery following ASCT was affected by insufficient hematopoietic recovery at stem cell harvest, a need for repeated apheresis, and high fever early after ASCT, particularly when the amount of infused stem cells was insufficient.

The effects of lower CD34 yields after lowe dose G-CSF induction on long-term autologous stem cell transplantation outcome: A single center study

Peripheral blood stem cell transplantation (PBSCT) is an effective treatment for hematological malignancies. Mobilization of peripheral blood stem cells performs in different ways among transplantation centers. Since the Effects of lower CD34+ cells dose after low dose G-CSF induction on autologous stem cell transplantation outcomes are not studied much, so this study was performed for this purpose. 735 autologous stem cell transplanted patients with diagnoses of multiple myeloma (n = 330), Hodgkin lymphoma (n = 200), non-Hodgkin lymphoma (n = 129), acute myeloid leukemia (n = 54) and solid tumors (n = 22) were retrospectively evaluated. G-CSF was administered at the dose of 5 μg/kg/day during mobilization and all patients except acute myeloid leukemia received 10 μg/kg/day on the last day. Peripheral blood stem cells were harvested in one session for all patients. The amount of injected CD34+ cells/kg for patients were divided and studied in four groups: <0.5 × 10⁶ (n = 36), 0.5-1.0 × 10⁶, (n = 132), 1.0-2.0 × 10⁶ (n = 226) and >2.0 × 10⁶ (n = 305). The median time of follow up was 26.9 months. The amount of CD34+ cells dose were a significant predictor of platelet engraftment, but overall survival, relapse-free survival and also relapse rate was not associated with cells yield. More platelet transfusion (P = 0.003) and antibiotics prescription (P = 0.001) in transplanted patients with lower CD34 cells dose should be balanced with risks of higher G-CSF doses administration and also its side effects. Our results declare that lower CD34 yields after lowe dose G-CSF induction are probably not a troublesome issue affecting transplantation outcomes.

Stem Cell Transplantation for Multiple Myeloma

BACKGROUND

Multiple myeloma (MM) is the second most common hematologic malignancy, affecting approximately 14,000 new patients in the United State per year. The median overall survival is 5 years, and cure is a realistic goal for only a small minority of patients.

METHODS

A review of the literature was conducted that focused on treatment strategies for MM involving administration of high doses of chemotherapy followed by autologous or allogeneic hematopoietic stem cell transplant.

RESULTS

For over three decades, the standard treatment for MM has been a regimen of melphalan and prednisone (MP). Complete responses (CRs) have been rare, and 50% of patients have had disease that was resistant to treatment with MP. Attempts have been made to improve the outcome of MM by administering other combinations of standard doses of chemotherapy, but these treatments are equivalent in terms of overall survival. For patients who are candidates, high-dose therapy followed by autologous stem cell transplantation results in higher CR rates and improved long-term survival compared to treatment with standard doses of chemotherapy alone. While this strategy represents an advance in the treatment of MM, evidence-based reviews indicate that there are a number of issues to consider regarding the induction therapy, the collection of stem cells, and the timing, type, and number of high-dose therapies to use in this type of treatment strategy.

CONCLUSIONS

Advances have been made in autologous transplantation, allogeneic transplantation, anti-MM agents, and immunotherapy for MM. Combining these different strategies to achieve synergistic responses is an exciting possibility.

Study of stem cell homing & self-renewal marker gene profile of ex vivo expanded human CD34+ cells manipulated with a mixture of cytokines & stromal cell-derived factor 1

BACKGROUND & OBJECTIVES

Next generation transplantation medicine aims to develop stimulating cocktail for increased ex vivo expansion of primitive hematopoietic stem and progenitor cells (HSPC). The present study was done to evaluate the cocktail GF (Thrombopoietin + Stem Cell factor + Flt3-ligand) and homing-defining molecule Stromal cell-derived factor 1 (SDF1) for HSPC ex vivo expansion.

METHODS

Peripheral blood stem cell (n=74) harvests were analysed for CD34hiCD45lo HSPC. Immunomagnetically enriched HSPC were cultured for eight days and assessed for increase in HSPC, colony forming potential in vitro and in vivo engrafting potential by analyzing human CD45+ cells. Expression profile of genes for homing and stemness were studied using microarray analysis. Expression of adhesion/homing markers were validated by flow cytometry/ confocal microscopy.

RESULTS

CD34hiCD45lo HSPC expansion cultures with GF+SDF1 demonstrated increased nucleated cells (n=28, P+ cells (n=8, P=0.021) and increased colony forming units (cfu) compared to unstimulated and GF-stimulated HSPC. NOD-SCID mice transplanted with GF+SDF1-HSPC exhibited successful homing/engraftment (n=24, PInterpretation & conclusions: Cocktail of cytokines and SDF1 showed good potential to successfully expand HSPC which exhibited enhanced ability to generate multilineage cells in short-term and long-term repopulation assay. This cocktail-mediated stem cell expansion has potential to obviate the need for longer and large volume apheresis procedure making it convenient for donors.

Hematologic recovery in patients who are treated with autologous stem cells transplantation taken from bone marrow after granulocyte-colony-stimulating factor stimulation

BACKGROUND

We sought to compare hematologic recovery between patients who did or did not receive granulocyte-colony-stimulating factor (G-CSF)-stimulated bone marrow (rich bone marrow [RBM]).

MATERIALS AND METHODS

The study subjects were 20 patients whose bone marrow was taken without prior stimulation with G-CSF and 15 patients in whom bone marrow was taken after previous G-CSF mobilization. The bone marrow harvest took place on the fifth day after G-CSF initiation. The bone marrow aliquot was 20 mL/kg.

RESULTS

The median value of nucleated cells obtained from patients without G-CSF preparation was 3.65×10(8)/kg. The median value of nucleated cells from RBM patients was 4.83×10(8)/kg. The median value of stem cells obtained from patients without G-CSF preparation was 0.96×10(6)/kg versus 1.9×10(6)/kg from RBM patients. The median time to recovery of the hematopoietic system based on an increase in PLT value>20 g/L was 12.6 days for RBM versus 18.8 days without G-CSF preparation. The median time to recovery of the hematopoietic system based on assessment of growth ANC>0.5 g/L was 13.0 days for RBM versus 17.8 days without G-CSF stimulation. Significantly higher values of nucleated cells and increased stem cells were observed among RBM patients compared with those whose bone marrow was harvested without any stimulation (P=.01). There was faster recovery of the hematopoietic system in cases where bone marrow was collected after G-CSF: PLT>20 g/L (P=.015) and ANC>0.5 g/L (P=.01). We also observed that the use of stimulated bone marrow shortened hospital stay after the administration of hematopoietic cells to 17.3 days compared with 23.1 days among patients receiving hematopoietic cells from nonstimulated bone marrow. The number of complications during transplantation was comparable in both cases, the most frequent ones being febrile neutropenia and grade III and IV mucositis.

CONCLUSION

RBM is a better method to obtain stem cells from bone marrow. Stimulated bone marrow shows faster engraftment compared with nonstimulated bone marrow helping patients who fail to generate are adequate number of stem cells from peripheral blood.

Mobilization strategies in hard-to-mobilize patients with lymphoid malignancies

Depending on definitions and patient characteristics, 5-40% of patients with lymphoid malignancies are hard-to-mobilize. Several premobilization factors such as previous chemotherapy (CT), disease, marrow infiltration and platelet count at the time of mobilization influence the efficacy of CD34(+) cell mobilization. In general, however, prediction of hard-to-mobilize patient is difficult. Postmobilization factors especially low blood CD34(+) counts are important in clinical practice as we have now ways to enhance mobilization at this point. Plerixafor combined with granulocyte-colony stimulating factor (G-CSF) has significantly increased efficacy of remobilization in patients who have failed a previous mobilization attempt with a success rate of about 70%. Addition of plerixafor to G-CSF or more recently to a mobilization regimen consisting of CT + G-CSF is promising as blood CD34(+) counts can be increased three to fivefold to facilitate effective collection with less aphaeresis sessions. As plerixafor is expensive, development of practical algorithms for its use is important to make blood stem cell mobilization and collection more efficient in a cost-effective way. This review attempts to summarize current treatment strategies in hard-to-mobilize patients with lymphoid malignancies.

Current status of stem cell mobilization

New advances in effective mobilization of peripheral blood stem cells have permitted a greater proportion of patients to benefit from autologous stem cell transplantation. In this review, the relative merits of peripheral blood and mobilized bone marrow are discussed. All available agents are reviewed. A critical assessment of the appropriate dosing and frequency of available growth factors is undertaken, and the most commonly used chemotherapy plus growth factor combinations are covered. Specific recommendations for patients who are poor mobilizers are dealt with including the role of plerixafor.

Positive selection and transplantation of autologous highly purified CD133(+) stem cells in resistant/relapsed chronic lymphocytic leukemia patients results in rapid hematopoietic reconstitution without an adequate leukemic cell purging

We assessed the capacity of positively selected autologous CD133(+) hematopoietic stem cells (HSCs) to reconstitute lymphomyelopoiesis in chronic lymphocytic leukemia (CLL) patients receiving myeloablative chemotherapy. Ten resistant/relapsed CLL patients underwent HSC mobilization with chemotherapy and granulocyte-colony stimulating factor (G-CSF). Positive selection of circulating CD133(+) HSCs was performed by immunomagnetic technique. Highly purified HSCs were reinfused after busulphan/melphalan myeloablative treatment. A median number of 4.2 x 10(6) CD34(+) cells/kg and of 3.14 x 10(6) CD133(+) cells/kg were collected. Immunomagnetic selection resulted in the reinfusion of a median number of 2.45 x 10(6) CD133(+) cells/kg (median purity: 94.8%; median recovery: 84%) and 2.4 x 10(6) CD34(+) cells/kg (median purity: 93%; median recovery: 71%). HSC selection resulted in a median T cell and CD19(+)/CD5(+) cell depletion of 3.85 log and 2.8 log, respectively. At the molecular level, however, 7 of 8 valuable purified HSC fractions were contaminated by leukemic cells. All CLL patients showed rapid and sustained myeloid engraftment after reinfusion of purified CD133(+) cells. Immunologic reconstitution was comparable to that routinely observed in patients reinfused with unmanipulated leukapheresis products and no late infectious complications were observed. With a median follow-up of 28 months for transplanted patients, 5 patients are in clinical complete remission, 3 are in partial remission, and 1 is in progression. In conclusion, the reinfusion of highly purified CD133(+) HSCs allowed the rapid and sustained recovery of hematopoiesis after myeloablative treatment in resistant/relapsed CLL patients. However, the purging potential of positive selection of CD133(+) cells is not adequate to achieve tumor-free autografts.

The chemokine GRObeta mobilizes early hematopoietic stem cells characterized by enhanced homing and engraftment

Mobilized peripheral blood hematopoietic stem cells (PBSCs) demonstrate accelerated engraftment compared with bone marrow; however, mechanisms responsible for enhanced engraftment remain unknown. PBSCs mobilized by GRObeta (GRObeta(Delta4)/CXCL2(Delta4)) or the combination of GRObeta(Delta4) plus granulocyte colony-stimulating factor (G-CSF) restore neutrophil and platelet recovery faster than G-CSF-mobilized PBSCs. To determine mechanisms responsible for faster hematopoietic recovery, we characterized immunophenotype and function of the GRObeta-mobilized grafts. PBSCs mobilized by GRObeta(Delta4) alone or with G-CSF contained significantly more Sca-1(+)-c-kit(+)-lineage(-) (SKL) cells and more primitive CD34(-)-SKL cells compared with cells mobilized by G-CSF and demonstrated superior competitive long-term repopulation activity, which continued to increase in secondary and tertiary recipients. GRObeta(Delta4)-mobilized SKL cells adhered better to VCAM-1(+) endothelial cells compared with G-CSF-mobilized cells. GRObeta(Delta4)-mobilized PBSCs did not migrate well to the chemokine stromal derived factor (SDF)-1alpha in vitro that was associated with higher CD26 expression. However, GRObeta(Delta4)-mobilized SKL and c-Kit(+) lineage(-) (KL) cells homed more efficiently to marrow in vivo, which was not affected by selective CXCR4 and CD26 antagonists. These data suggest that GRObeta(Delta4)-mobilized PBSCs are superior in reconstituting long-term hematopoiesis, which results from differential mobilization of early stem cells with enhanced homing and long-term repopulating capacity. In addition, homing and engraftment of GRObeta(Delta4)-mobilized cells is less dependent on the SDF-1alpha/CXCR4 axis.

Impact of different strategies of second-line stem cell harvest on the outcome of autologous transplantation in poor peripheral blood stem cell mobilizers

The optimal approach to obtain an adequate graft for transplantation in patients with poor peripheral blood stem cell (PBSC) mobilization remains unclear. We retrospectively assessed the impact of different strategies of second-line stem cell harvest on the transplantation outcome of patients who failed PBSC mobilization in our institution. Such patients were distributed into three groups: those who proceeded to steady-state bone marrow (BM) collection (group A, n = 34); those who underwent second PBSC mobilization (group B, n = 41); those in whom no further harvesting was carried out (group C, n = 30). PBSC harvest yielded significantly more CD34+ cells than BM collection. Autologous transplantation was performed in 30, 23 and 11 patients from groups A, B and C, respectively. Engraftment data and transplantation outcome did not differ significantly between groups A and C. By contrast, group B patients had a faster neutrophil recovery, required less platelet transfusions and experienced less transplant-related morbidity, as reflected by lower antibiotics needs and shorter hospital stays. In conclusion, remobilization of PBSC constitutes an effective approach to ensure a rapid hematopoietic engraftment and a safe transplantation procedure for poor mobilizers, whereas unprimed BM harvest does not provide any clinical benefit in this setting.

The role of diagnosis in patients failing peripheral blood progenitor cell mobilization

BACKGROUND

Failure to mobilize PBPCs for auto-logous transplantation has mostly been attributed to previous therapy and poses therapeutic problems.

STUDY DESIGN AND METHODS

The role of underlying disease was analyzed in 17 of 73 (23%) patients with PBPC mobilization failure, and secondary mobilization with high-dose filgrastim was attempted.

RESULTS

Of 16 patients with acute leukemia, 13 (81%) mobilized poorly. In contrast, of 57 patients with non-Hodgkin's lymphoma, Hodgkin's lymphoma, multiple myeloma, and solid tumor, 53 (93%, p < 0.001) showed good PBPC mobilization. Relapsed disease did not predispose to poor mobilization. As secondary mobilization attempt, 7 patients received 25 micro g per kg per day filgrastim without chemotherapy leading to a 3.7 +/- 2.8-fold (SD) increase in the maximum number of circulating CD34+ cells (p = 0.104). PBPC apheresis yielded 3.3 (+/-0.5) x 10(6) CD34+ cells per kg of body weight in 5 patients. Four poor mobilizers received 50 micro g per kg per day filgrastim as second or third mobilization attempt. Circulating CD34+ cells in these patients increased by 1.5 (+/-0.7) compared with the primary G-CSF application.

CONCLUSION

Selective PBPC mobilization failure was seen in patients with acute leukemia whereas remarkably good mobilization was seen in other malignancies. Increasing the filgrastim dose to 25 micro g per kg per day may allow PBPC collection in patients failing PBPC mobilization.

Prediction of mobilisation failure in patients with non-Hodgkin's lymphoma

Factors affecting progenitor cell mobilisation in patients with non-Hodgkin's lymphoma (NHL) are incompletely understood. We have analysed factors predicting mobilisation failure in 97 consecutive patients with NHL (59 males, 38 females; median age 49 years) who received mobilisation with intermediate-dose CY (4 g/m(2)) followed by G-CSF. The histology included large cell B (N=50), mantle cell (N=16), follicular (N=16) and other NHL (N=15). The disease status was 1CR/PR/primary refractory in 66 patients and >1 CR/PR in 31 patients. The minimum criterion for successful mobilisation was the collection of >or=1.5 x 10(6)/kg CD34(+) cells. In all, 18 patients (19%) failed to reach this threshold. In univariate analysis, premobilisation factors associated with mobilisation failure included BM involvement at the time of diagnosis (P=0.001) or prior to mobilisation (P=0.001) and low platelet count just prior to mobilisation (P=0.001). In multivariate analysis, only BM involvement at diagnosis (P=0.004) and platelet count just prior to mobilisation (P=0.01) were associated with mobilisation failure. A mathematical model based on these two factors and presented in the form of a receiver operating characteristics curve showed a sensitivity of 0.71 and a specificity of 0.77 in the prediction of mobilisation failure. Patients at a high risk of mobilisation failure may benefit from novel approaches.