Transient spleen enlargement in peripheral blood progenitor cell donors given G-CSF

The administration of granulocyte colony-stimulating factor (G-CSF) to peripheral blood progenitor cell (PBPC) donors causes spleen length to increase, but the duration of enlargement is not known. Eighteen healthy subjects were given 10 μg/kg of G-CSF for 5 days and a PBSC concentrate was collected by apheresis. Ultrasound scans were used to assess craniocaudal spleen length before and after G-CSF administration. Mean spleen length increased from a baseline length of 10.7 ± 1.3 cm to 12.1 ± 1.2 cm on the apheresis day (p < 0.001). Ten days after apheresis, spleen length fell to 10.5 ± 1.2 cm and did not differ from baseline levels (p = 0.57), but in 3 subjects remained 0.5 cm greater than baseline length. Increases in spleen length in PBPC donors are transient and reversible.     

Effect of G-CSF on peripheral blood progenitor cell mobilization and collection from healthy donors

We studied granulocyte colony-stimulating factor (G-CSF) mediated peripheral blood progenitor cells (PBPC), which were mobilized and collected from healthy donors for allogeneic transplantation. A total of 26 donors, age ranged from 21-41 years were mobilized with G-CSF at a dose of 7.5 microg/kg/day subcutaneously for 5 days and the collection was started on day 5. The CD34 cell counts reached a maximum on day 5 and subsequently declined despite continually given G-CSF. White blood cells (WBC), absolute neutrophil counts (ANC), absolute lymphocytes (AL) and their subsets, absolute mononuclear cells (AMNC), colony-forming unit-granulocyte, macrophage (CFU-GM) and CD34+ cells were increased about 6, 9, 2, 3, 34 and 40-fold, respectively, but red blood cells (RBC), hematocrit (Hct) and platelets (Pit) decreased on day 5 when compared to day 0. All parameters decreased after stem cell collection. For stem cell collection by Cobe Spectra, we used a blood volume of 19.27 +/- 4.65 liters, flow rate of 60.53 +/- 10.03 ml/minute, acid citrate dextrose solution (ACD)/blood ratio of 1:13.31, the final product volume was 314.14 +/- 72.24 ml, collection time was 325.40 +/- 73.36 minutes and one or two procedures were sufficient. The correlation between the number of CD34+ cells/kg, CFU-GM/kg and MNC/kg found in the harvested product and CD34 cells can be used for determining the necessary amount of progenitor cells for transplantation.     

Delayed administration of G-CSF in both mobilization and post transplantation in autologous peripheral blood stem cell transplantation

Granulocyte colony stimulating factors (G-CSFs) play a very important role in the current technique of stem cell transplantation. The conventional timing of administration of G-CSF in both mobilization and post transplantation has been right after chemotherapy or right after transplantation. We have studied the effects of timing of administration of G-CSF in 21 patients who had autologous stem cell transplantation for breast cancer, lymphoma or nasopharyngeal cancer. Their stem cells were mobilized by chemotherapy followed by G-CSF, which were given on day +1 or day +5 after chemotherapy. The median peak percentage of CD34 positive cells harvested using both technique were 1.88 and 0.48% respectively. After transplantation, G-CSF were given on day +1 or day +6 after stem cell infusion until neutrophil recovery. The time until bone marrow recovery was significantly longer in the group with delayed administration of G-CSF (10 days versus 8 days). However, there was no difference in duration of neutropenic fever or hospital stay after transplantation. The transplantation outcome was also unaffected. We therefore concluded that G-CSF can be given in the delayed fashion in both mobilizing and post transplantation settings without jeopardizing the outcome and this would result in a significant cost saving.     

Bronchial epithelial cell-derived cytokines (G-CSF and GM-CSF) promote the survival of peripheral blood neutrophils in vitro.

Neutrophil accumulation in the respiratory tract occurs in a variety of inflammatory disorders, particularly those associated with cigarette smoking. We examined whether bronchial epithelial cells could contribute to this accumulation through the production of factors that increased the survival of neutrophils. Pure primary cultures of human bronchial epithelial cells (HBEC) were used to generate conditioned medium (CM), and the effect of this CM on the survival of neutrophils in vitro was examined. When neutrophils were cultured in control medium, survival was 8.7 +/- 1.7% at 72 h. In contrast, culture of neutrophils in CM resulted in a dose-dependent increase in survival: 22.6 +/- 5.5, 43.6 +/- 4.2, and 64 +/- 3.8% in 1, 10, and 50% CM respectively (mean +/- SEM; P < 0.05). As evidenced by the examination of neutrophil DNA, this prolongation of survival was associated with suppression of apoptosis. Cytokines with known actions on neutrophil biology identified in the CM included granulocyte colony-stimulating factor (G-CSF), granulocyte/macrophage colony-stimulating factor (GM-CSF), and interleukin-8. Through the use of specific neutralizing antibodies, G-CSF and GM-CSF were identified as promoting neutrophil survival. Neutrophil survival was prolonged in the presence of either recombinant human (rh) G-CSF or rhGM-CSF alone in a dose-dependent fashion. In contrast to the response of eosinophils to HBEC-CM, steroid treatment did not prevent the increase in neutrophil survival induced by HBEC-CM. In summary, we show that bronchial epithelial cells markedly increase the survival of human neutrophils in vitro via the release of G-CSF and GM-CSF.(ABSTRACT TRUNCATED AT 250 WORDS)     

G-CSF and GM-CSF concentrations and receptor expression in peripheral blood leukemic cells from patients with chronic myelogenous leukemia

Granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage-CSF (GM-CSF) are the principal cytokines in granulopoiesis and differentiation of granulocytic precursors. Their physiologic effects are mediated by binding to specific cell surface receptors (G-CSFr and GM-CSFr, respectively), which are widely expressed from immature bone marrow cells to mature peripheral granulocytes. The fact that concentrations of plasma G-CSF and GM-CSF and their receptors are changed in infectious diseases showing neutrophilia is known, but such changes in patients with chronic myelogenous leukemia (CML) have not been studied. Based on quantitative assays of plasma G-CSF and GM-CSF and their receptors on the peripheral granulocytes of CML patients and healthy controls, this study analyzes the differences between these groups in G-CSF and GM-CSF levels, as well as quantitative and qualitative changes in the receptors. Plasma levels of G-CSF and GM-CSF were measured in 47 patients in the chronic phase of CML and 25 healthy adults as normal controls. G-CSFr and GM-CSFr on peripheral granulocytes were analyzed by quantitative flow cytometry, and changes in G-CSF and GM-CSF receptor counts were also measured. Plasma concentrations of G-CSF and GM-CSF in CML patients were similar to normal controls (p>0.05). The quantity of G-CSFr on neutrophils was more highly expressed than on other cell types in both groups, and the amount of this receptor in patients with CML was less than in normal controls (p=0.001). GM-CSFr was expressed in higher concentrations on monocytes than neutrophils, and there was no difference in the amount of GM-CSFr on neutrophils. After incubation with excess G-CSF, the expressed amounts of G-CSFr on neutrophils and monocytes were decreased in both groups. However, G-CSFr on the monocytes was decreased in healthy controls (p=0.02) with no difference in patients with CML. The quantities of GM-CSFr expression on neutrophils and monocytes after incubation with excess GM-CSF were decreased in both groups. Granulocyte counts in peripheral blood of CML patients were not correlated with the plasma concentrations of G-CSF or GM-CSF, nor with the expression of G-CSFr or GM-CSFr on granulocytes. Granulopoiesis in patients with CML was not mediated by increased plasma CSF concentrations, and there was no difference in the amounts of G-CSFr or GM-CSFr expressed on the granulocytes. This suggests that a structural change may occur on monocytes of CML patients, since the binding capacity of G-CSFr to G-CSF on the monocytes is different from the normal controls.     

No polarization of type 1 or type 2 precursor dendritic cells in peripheral blood stem cell collections of non-hodgkin's lymphoma patients mobilized with cyclophosphamide plus G-CSF, GM-CSF, or GM-CSF followed by G-CSF

Dendritic cells (DCs) are the most efficient antigen-presenting cells and play a role in immune reconstitution after autologous transplantation. Recent reports suggest that mobilization with granulocyte colony-stimulating factor (G-CSF) containing regimens polarizes DCs into pDC2, which could potentially result with increased Th2 response and decreased graft-versus-host disease (GVHD) in allogeneic transplantation and with decreased cytotoxic Th1 response and graft versus tumor effect, which in autologous transplantation could translate into increased relapse rate. Previously, we have shown that non-Hodgkin's lymphoma (NHL) patients receiving cyclophosphamide (CTX) plus granulocyte- macrophage (GM)-CSF, G-CSF or GM-CSF followed by G-CSF for stem cell collection, mobilize up to five-fold more mature CD80(+) DCs compared to CTX plus G-CSF mobilized patients. Here, we analyzed samples from the same study for the number of pDC1 and pDC2 subsets in blood and apheresis products obtained from these patients. Samples from 29 patients were collected. Patients mobilized with CTX plus G-CSF collected a mean of 1.2 +/- 0.4 x 10(6) pDC1/kg per day and 2.2 +/- 1 x 10(6) pDC2/kg per day, whereas patients mobilized with CTX plus GM-CSF collected a mean of 1.1 +/- 0.5 x 10(6) pDC1 and 1.5 +/- 0.9 x 10(6) pDC2/kg per day. Patients mobilized with CTX plus GM-CSF followed by G-CSF collected 2.5 +/- 1.1 x 10(6) pDC1 and 2 +/- 0.5 x 106 pDC2/kg per day, with significantly higher levels of pDC1 +/- pDC2 cells. No significant difference was observed in pDC1/pDC2 ratio between the three mobilization arms. Patients mobilized with the GM-CSFcontaining regimen had a higher probability for survival compared to patients receiving G-CSF alone (median of 55 months vs. 15 months; p = 0.02). These results support the hypothesis that higher levels of DCs in the graft might be associated with prolonged survival of autotransplanted NHL patients. Further similar studies are merited in a larger population of NHL patients.     

Changes in immunological recovery in patients who received post-transplant G-CSF or GM-CSF after autologous peripheral blood stem cell transplantation (PBSCT)

In this prospective study, the effects of granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) on immunological reconstitution after autologous peripheral blood stem cell transplantation (PBSCT) were investigated for 6 months. Thirty-five patients received G-CSF 5 microg/kg per day and 26 patients received GM-CSF SC 5 microg/kg per day from day 1 to leukocyte engraftment (>1000 per mm3). Peripheral blood samples were obtained on 14, 28, 100, and 180 days after transplantation for immunological evaluation. CD3+, CD4+, CD8+, CD19+, and CD56+ cells were analysed by flow cytometry. Immunoglobulin levels (IgG, IgA, and IgM) and complement levels (C3c and C4) were measured by nephelometry. Both G-CSF and GM-CSF groups were comparable with respect to age, sex, the period from diagnosis to transplantation, total nucleated cells infused, the number of CD34+ cells, conditioning regimens (TBI and non-TBI), and post-transplant infection. CD3+ and CD8+ cells on day 14 following autologous PBSCT + G-CSF were significantly higher than following autologous PBSCT + GM-CSF (p = 0.008 and p = 0.021, respectively). The number of CD4 cells and the CD4/CD8 ratio were not different at several time points between the two groups. CD19+, CD56+ cells and immunoglobulin levels showed a faster recovery pattern in the autologous PBSCT + G-CSF group. The effect of G-CSF on immune reconstitution after autologous PBSCT is more prominent than that of GM-CSF. The possible role of haematopoietic growth factor on immune recovery and its clinical importance should be investigated in further studies.     

Matched-pair analysis of hematopoietic progenitor cell mobilization using G-CSF vs. cyclophosphamide, etoposide, and G-CSF: enhanced CD34+ cell collections are not necessarily cost-effective.

Using matched-pair analysis, we compared two popular methods of stem cell mobilization in 24 advanced-stage breast cancer patients who underwent two consecutive mobilizing procedures as part of a tandem transplant protocol. For the first cycle, 10 microg/kg/day granulocyte colony-stimulating factor (G-CSF) was given and apheresis commenced on day 4 and continued for < or =5 days (median 3 days). One week after the first cycle of apheresis, 4000 mg/m2 cyclophosphamide, 400 mg/m2 etoposide, and 10 microg/kg G-CSF were administered for < or =16 days (cycle 2). Apheresis was initiated when the white blood cell (WBC) count exceeded 5000 cells/microL and continued for < or =5 days (median 3 days). Mean values of peripheral blood WBC (31,700+/-3200 vs. 30,700+/-3300/microL) were not significantly different between cycles 1 and 2. Mean number of mononuclear cells (MNC) collected per day was slightly greater with G-CSF mobilization than with the combination of chemotherapy and G-CSF (2.5+/-0.21x10(8) vs. 1.8+/-0.19x10(8) cells/kg). Mean daily CD34+ cell yield, however, was nearly six times higher (12.9+/-4.4 vs. 2.2+/-0.5x10(6)/kg; p = 0.01) with chemotherapy plus G-CSF. With G-CSF alone, 13% of aphereses reached the target dose of 5x10(6) CD34+ cells/kg in one collection vs. 57% with chemotherapy plus G-CSF. Transfusions of red blood cells or platelets were necessary in 18 of 24 patients in cycle 2. Three patients were hospitalized with fever for a median of 3 days after cycle 2. No patients received transfusions or required hospitalization during mobilization with G-CSF alone. Resource utilization (cost of drugs, aphereses, cryopreservation, transfusions, hospitalization) was calculated comparing the median number of collections to obtain a target CD34+ cell dose of 5x10(6) cells/kg: four using G-CSF vs. one using the combination in this data set. Resources for G-CSF mobilization cost $7326 vs. $8693 for the combination, even though more apheresis procedures were performed using G-CSF mobilization. The cost of chemotherapy administration, more doses of G-CSF, transfusions, and hospitalizations caused cyclophosphamide, etoposide, and G-CSF to be more expensive than G-CSF alone. A less toxic and less expensive treatment than cyclophosphamide, etoposide, and G-CSF is needed to be more cost-effective than G-CSF alone for peripheral blood progenitor cell mobilization.     

Engraftment of primates with G-CSF mobilized peripheral blood CD34+ progenitor cells expanded in G-CSF, SCF and MGDF decreases the duration and severity of neutropenia.

We used a primate model of autologous peripheral blood progenitor cell (PBPC) transplantation to study the effect of in vitro expansion on committed progenitor cell engraftment and marrow recovery after transplantation. Four groups of baboons were transplanted with enriched autologous CD34+ PBPC collected by apheresis after five days of G-CSF administration (100 microg/kg/day). Groups I and III were transplanted with cryopreserved CD34+ PBPC and Groups II and IV were transplanted with CD34+ PBPC that had been cultured for 10 days in Amgen-defined (serum free) medium and stimulated with G-CSF, megakaryocyte growth and development factor (MGDF), and stem cell factor each at 100 etag/ml. Group III and IV animals were administered G-CSF (100 microg/kg/day) and MGDF (25 microg/kg/day) after transplant, while animals in Groups I and II were not. For the cultured CD34+ PBPC from groups II and IV, the total cell numbers expanded 14.4 +/- 8.3 and 4.0 +/- 0.7-fold, respectively, and CFU-GM expanded 7.2 +/- 0.3 and 8.0 +/- 0.4-fold, respectively. All animals engrafted. If no growth factor support was given after transplant (Groups II and I), the recovery of WBC and platelet production after transplant was prolonged if cells had been cultured prior to transplant (Group II). Administration of post-transplant G-CSF and MGDF shortened the period of neutropenia (ANC < 500/microL) from 13 +/- 4 (Group I) to 10 +/- 4 (Group III) days for animals transplanted with non-expanded CD34+ PBPC. For animals transplanted with ex vivo-expanded CD34+ PBPC, post-transplant administration of G-CSF and MGDF shortened the duration of neutropenia from 14 +/- 2 (Group II) to 3 +/- 4 (Group IV) days. Recovery of platelet production was slower in all animals transplanted with expanded CD34+ PBPC regardless of post-transplant growth factor administration. Progenitor cells generated in vitro can contribute to early engraftment and mitigate neutropenia when growth factor support is administered post-transplant. Thrombocytopenia was not decreased despite evidence of expansion of megakaryocytes in cultured CD34+ populations.     

Randomized trial of allogeneic related bone marrow transplantation versus peripheral blood stem cell transplantation for chronic myeloid leukemia.

Seventy-two chronic myeloid leukemia patients were enrolled as part of a larger randomized trial at 3 centers between March 1996 and July 2001 to undergo either HLA-matched related allogeneic bone marrow (BM) or filgrastim (granulocyte colony-stimulating factor)-mobilized peripheral blood stem cell (PBSC) transplantation. Forty patients received BM, and 32 patients received PBSCs. There was no statistically significant difference in the incidence of acute or chronic graft-versus-host disease (GVHD), overall survival, disease-free survival, or non-relapse-related mortality between patients receiving BM or PBSC transplants. The cumulative incidence of grade II to IV acute GVHD was 49% in BM and 55% in PBSC recipients ( P = .48). The cumulative incidence of clinical extensive chronic GVHD was 50% in BM and 59% in PBSC recipients ( P = .46). Among 62 chronic phase chronic myeloid leukemia patients, there was no significant difference in overall survival (87% versus 81%; P = .59), disease-free survival (80% versus 81%; P = .61), or non-relapse-related mortality (13% versus 19%; P = .60) by cell source (BM versus PBSCs). Among chronic phase patients, however, there was a trend toward a higher cumulative incidence of relapse at 3 years in BM recipients (7% versus 0%; P = .10) and a higher cumulative incidence of chronic GVHD in PBSC recipients (59% versus 40%; P = .11). The trend toward a higher relapse incidence in BM recipients persisted with a longer follow-up.     

Repeated hematopoietic stem and progenitor cell mobilization without depletion of the bone marrow stem and progenitor cell pool in mice after repeated administration of recombinant murine G-CSF

Administration of recombinant-human G-CSF (rhG-CSF) is highly efficient in mobilizing hematopoietic stem and progenitor cells (HSC/HPC) from the bone marrow (BM) toward the peripheral blood. This study was designed to investigate whether repeated G-CSF-induced HSC/HPC mobilization in mice could lead to a depletion of the bone marrow HSC/HPC pool with subsequent loss of mobilizing capacity. To test this hypothesis Balb/c mice were treated with a maximum of 12 repeated 5-day cycles of either 10 microg rhG-CSF/day or 0.25 microg rmG-CSF/day. Repeated administration of rhG-CSF lead to strong inhibition of HSC/HPC mobilization toward the peripheral blood and spleen after >4 cycles because of the induction of anti-rhG-CSF antibodies. In contrast, after repeated administration of rmG-CSF, HSC/HPC mobilizing capacity remained intact for up to 12 cycles. The number of CFU-GM per femur did not significantly change for up to 12 cycles. We conclude that repeated administration of G-CSF does not lead to depletion of the bone marrow HSC/HPC pool.     

G-CSF动员的骨髓及外周血干细胞移植治疗重型再生障碍性贫血

采用G CSF动员的骨髓以及外周血造血干细胞移植治疗重型再生障碍性贫血 (SAA)。共有 10例重型再生障碍性贫血患者接受了G CSF动员的骨髓以及外周血造血干细胞移植 ,回顾性分析植入情况、植入速度及急慢性移植物抗宿主病 (GVHD)发生率等。所有患者移植后均获得造血重建。中性粒细胞计数 (ANC) >0 5× 10 9L- 1 的中位时间为 13 2d(8～ 18) ,血小板 >2 0× 10 9L- 1 的中位时间为 2 2 2d(10～ 10 8)。 8例获得异体植入的患者中 3例发生Ⅰ Ⅱ度皮肤急性GVHD ,发生 5例慢性GVHD。至随访截止 ,中位随访 775d(2 10～ 14 2 9) ,所有 10例患者均无病存活(DFS)。因此我们认为G CSF动员的骨髓及外周血干细胞移植是治疗SAA的有效方法 ,可获得快速、持久植入 ,而不增加急性和慢性GVHD的发生率。     

Elevation of platelet activation markers and chemokines during peripheral blood stem cell harvest with G-CSF

The kinetics of peripheral blood stem cell mobilization in response to recombinant human granulocyte colony-stimulating factor is well established. However, there have been few investigations of platelet activation markers during peripheral blood stem cell harvest. We measured the levels of the platelet activation markers, chemokines, and soluble factors in plasma obtained from patients undergoing peripheral blood stem cell harvest. The number of leukocytes, CD34+ cells, neutrophils, monocytes, and lymphocytes peaked on day 5 after granulocyte colony-stimulating factor treatment, but the numbers of eosinophils and basophils showed no significant change. Regulated on activation normally T-cell expressed and secreted (RANTES) level increased through day 10, and the monocyte chemotactic peptide-1 (MCP-1) level peaked on day 5. Platelet counts continued to increase through day 10. The level of thrombopoietin significantly increased on day 3, peaked on day 5, and decreased slightly by day 10. The levels of soluble CD40 ligand and soluble P-selectin increased up to day 5. The platelet-derived microparticle level peaked on day 5, and then began to decline. CD34+ cell numbers significantly correlated with those of leucocytes, neutrophils, monocytes, and lymphocytes, as well as levels of MCP-1, and the CD34+ cells exhibited changes similar to platelet-derived microparticles. The patterns of change in MCP-1, platelet-derived microparticles, and the CD34+ cell count are similar in that each peaks on day 5 and decreases thereafter. Further study is required to determine if a cause-and-effect relationship in their pattern of change exists among them.     

两种血细胞分离机干/祖细胞采集和移植效果的比较

背景：外周血造血干/祖细胞通过血细胞分离机进行体外收集,血细胞分离机的性能、工作状况将直接关系到采集物的特性和数量,从而直接影响受者的造血重建。 目的：比较Fenwal CS-3000 Plus与Amicus两种血细胞分离机采集外周血造血干/祖细胞及受者移植效果。 方法：共入选接受异基因外周血干细胞移植患者51例,Fenwal CS-3000 Plus组27例,平均年龄(34.2±10.6)岁;Amicus组24例,平均年龄(35.4±12.1)岁。比较两组采集物有核细胞数、CD34+细胞数、采集效率、红细胞与血小板采集量及造血重建时间。 结果与结论：两组采集物的有核细胞数、CD34+细胞数、采集效率、红细胞采集量及造血重建时间差异均无显著性意义;Fenwal CS-3000Plus组血小板采集量明显高于Amicus组(P < 0.01)。结果显示Fenwal CS-3000 Plus与Amicus血细胞分离机在分离外周血干/祖细胞方面和移植效果没有差异;血小板较低被采集者使用Amicus血细胞分离机采集可能更为安全。     

Use of thrombopoietin in combination with chemotherapy and granulocyte colony-stimulating factor for peripheral blood progenitor cell mobilization.

This phase I/II dose-escalation study examined the safety and efficacy of recombinant human thrombopoietin (rhTPO) and granulocyte colony-stimulating factor (G-CSF) for postchemotherapy mobilization of peripheral blood progenitor cells (PBPCs) in patients with advanced breast cancer. Patients received cyclophosphamide, etoposide, and cisplatin (CVP) followed by G-CSF (6 microg/kg twice a day) and rhTPO (0.6, 1.2, 2.4, or 3.6 microg/kg as a single dose on day 5 or as 3 doses on days 5, 7, and 9 after chemotherapy). PBPCs were collected by daily leukapheresis when the postnadir white blood cell count reached > or = 2 x 10(9)/L; leukapheresis was continued until acquisition of a target dose of > or = 5 x 10(6) CD34+ cells/kg. Mobilized PBPCs were transplanted into patients after additional high-dose chemotherapy with cyclophosphamide, carmustine, and thiotepa (CBT). Comparisons were made with contemporaneously treated, nonrandomized, control patients who received the same chemotherapy regimens and G-CSF support but who did not receive rhTPO. Of 32 evaluable patients receiving rhTPO and G-CSF after CVP, 91% required only 1 leukapheresis to achieve a target PBPC graft; by contrast, only 69% of 36 of the control patients achieved the target graft with just 1 leukapheresis (P = .026). A median of 26.7 x 10(6) CD34 cells/kg per leukapheresis was obtained from the rhTPO-treated patients compared with 11.5 x 10(6) cells/kg per leukapheresis from the controls (P = .09). Higher rhTPO doses appeared to yield more CD34+ cells. When PBPCs were infused after high-dose CBT chemotherapy, the median times to return of an absolute neutrophil count of 0.5 x 10(9)/L and a platelet count of 20 x 10(9)/L were 15 and 16 days, respectively; these values did not differ from those in the control group (15 days for both neutrophil and platelets). No patient developed anti-TPO antibodies. These results indicate that rhTPO safely and effectively augments the number of PBPCs mobilized with chemotherapy and G-CSF and can reduce the required number of leukaphereses. Further studies are also warranted in patients who are likely to experience suboptimal PBPC mobilization when treated with currently available techniques.     

Tandem-cycle high-dose melphalan and cisplatin with peripheral blood progenitor cell support in patients with breast cancer and other malignancies.

We evaluated the feasibility of tandem-cycle high-dose chemotherapy (HDCT) with cisplatin, melphalan, and peripheral blood progenitor cells (PBPCs). Fifty patients with high-risk primary (n = 17) or stage IV breast cancer (n = 29) or other malignancies (n = 4) received 2 cycles of intravenous melphalan, 20 to 151.8 mg/m2, and cisplatin, 200 mg/m2, followed by granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF. Starting at 40 mg/m2 of melphalan, patients also received PBPCs. Delayed platelet recovery defined the maximum tolerated dose (MTD) for melphalan at 101.2 mg/m2 per cycle. There were no treatment-related deaths. Cycle 2 was delivered at a median of 1.7 months after cycle 1; 72% of patients treated at the MTD received both cycles. Cycle 2 was omitted when patients refused it or had disease progression or toxicities, primarily prolonged thrombocytopenia. Complete response rates in stage IV breast cancer patients increased from 28% pre-HDCT to 55% after cycle 2. At a median follow-up of 4.6 years (range, 1.5-8.1 years), 11 of 29 patients with stage IV breast carcinoma were alive with 5-year projected progression-free and overall survival rates of 19% (95% confidence interval [CI], 7%-41%) and 39% (95% CI, 20%-62%), respectively. Five-year projected progression-free and overall survival rates for patients with stage IV breast cancer in complete response following HDCT versus all others were 35% (95% CI, 15%-70%) versus 0% (P = .01) and 61% (95% CI, 35%-91%) versus 10% (95% CI, 2%-60%) (P = .003; log-rank test), respectively. Estrogen-receptor positivity was predictive of reduced risk of progression (relative risk [RR], 0.25; 95% CI, 0.10-0.65; P = .003) and death (RR, 0.27; 95% CI, 0.10-0.72; P = .009) after adjusting for response status. Five-year projected relapse-free and overall survival rates were 71% (95% CI, 43%-96%) and 82% (95% CI, 56%-100%), respectively, for the 17 patients with high-risk primary breast cancer. Tandem-cycle high-dose melphalan and cisplatin with PBPCs is feasible. Preliminary data suggest significant activity in selected patients with stage IV responding breast carcinoma.     

The possible cost effectiveness of peripheral blood stem cell mobilization with cyclophosphamide and the late addition of G-CSF

The purpose of this study was to develop a cost-effective protocol for the mobilization of peripheral blood stem cells (PBSC) in patients with malignancy. Thirty consecutive patients were randomized to mobilize PBSC with the late addition of a standard 250 microg dose of G-CSF (Neutrogen) from day 8 or early addition of the same dose of G-CSF from day 2, following cyclophosphamide (CY) 4 g/m2. The median yield of CD34+ cells from evaluated patients was 7.87 x 10(6)/kg (range, 2.06-27.25), collected in a median of four apheresis (range, 2-9). Target CD34 + cell doses > or = 2.0 x 10(6)/kg were achieved in all patients able to be evaluated. There were no statistically significant differences in CD34+ cell yields or toxicities. Overall engraftment occurred with median days to neutrophils > or = 0.5 x 10(9)/L or platelets > 20 x 10(9)/L of 11 and 17 days, respectively. However, the duration of G-CSF administration was markedly shorter in the late use of G-CSF group than in the early use of G-CSF group, with a median of 9 days compared with 15 days (p<0.001). PBSC harvesting after priming with CY plus delayed use of G-CSF made it a safe and cost-effective procedure.     

An alternative flow cytometry strategy for peripheral blood dendritic cell enumeration in the setting of repetitive GM-CSF dosing

Background  

Enumeration of circulating peripheral blood dendritic cells (DCs) is complicated by the absence of a unique cell surface marker expressed on all DC subsets and by the use of various biological adjuvants to modulate the DC compartment, including granulocyte macrophage colony stimulating factor (GM-CSF). Common methods employ a cocktail of antibodies, typically including anti-CD14, to define a lineage negative, MHC class II positive, putative DC population. Reported flow cytometry protocols include highly variable gating strategies and DC identification criteria. Increasing appreciation of DC pleiomorphism, GM-CSF biology, and recognition of CD14 expression in some DC subsets led us to consider an alternative lineage cocktail to improve identification of the circulating DC pool.