Large-volume leukapheresis using femoral venous access for harvesting peripheral blood stem cells with the Fenwal CS 3000 Plus from normal healthy donors: predictors of CD34+ cell yield and collection efficiency

The current paper reports on the predicting factors associated with satisfactory peripheral blood stem cell collection and the efficacy of large-volume leukapheresis (LVL) using femoral vein catheterization to harvest PBSCs with Fenwal CS 3000 Plus from normal healthy donors for allogeneic transplantation. A total of 113 apheresis procedures in 57 patients were performed. The median number of MNCs, CD3+ cells, and CD34+ cells harvested per apheresis was 5.3 x 10(8)/kg (range, 0.3-11.0 x 10(8)/kg), 3.0 x 10(8)/kg (range, 0.2-6.6 x 10(8)/kg), and 7.9 x 10(6)/kg (range, 0.1-188.9 x 10(6)/kg), respectively. The median collection efficiency of MNCs and CD34+ cells was 49.8% and 49.7%, respectively. A highly significant correlation was found between the collected CD34+ cell counts and the pre-apheresis WBC counts in the donors (P = 0.013), and between the collected CD34+ cell counts and the pre-apheresis peripheral blood (PB) CD34+ cell counts (P<0.001). Harvesting at least >4 x 10(6)/kg CD34+ cells from the 1st LVL was achieved in 44 (77.2%) out of 57 donors and in 19 (90.5%) out of 21 donors with a PB-CD34+ cell count of >40/microl. There was no significant difference in the harvested MNC and CD34+ cell counts between the 1st and 2nd apheresis. The catheter-related complications included catheter obstruction (n = 2) and hematoma at the insertion site (n = 3). Accordingly, LVL using femoral venous access for allogeneic PBSC collection from normal healthy donors would appear to be safe and effective.     

A randomized trial of leukapheresis volumes, 7 L versus 10 L: an assessment of efficacy and patient tolerance

High-dose chemotherapy followed by autologous PBSC transplantation (PBSCT) has become an accepted form of therapy for a number of malignant hematologic diseases. The optimal method for the collection of PBSC is yet to be defined. Large-volume leukapheresis may be able to collect adequate numbers of PBSC with the patient undergoing fewer procedures. We routinely process 7 L of blood per leukapheresis. Hence, we elected to assess whether a modest increase in the blood volume processed would, on average, decrease the number of leukaphereses each patient needed to undergo to collect > or =2 x 10(6) CD34+ cells/kg body weight. Sixty patients were randomized to undergo 7 L leukaphereses (n = 31 patients; 87 leukaphereses) or 10 L leukaphereses (n = 29 patients; 81 leukaphereses). The median number of leukaphereses required per patient to collect the target number of CD34+ cells was two (range one to five) for both groups (p = 0.83). The median number of nucleated cells collected per patient was greater for the 10 L group (8.2 x 10(8)/kg versus 5.3 x 10(8)/kg, p = 0.005), as was the median number of mononuclear cells (MNC) (4.7 x 10(8)/kg versus 3.6 x 10(8)/kg, p = 0.0001), whereas there was no statistical difference between the groups for the median number of CD34+ cells collected per patient (3.2 x 10(6)/kg versus 3.7 x 10(6)/kg, p = 0.98). Therefore, over the 18-month period of this trial, the use of a 10 L leukapheresis volume did not decrease the number of leukaphereses performed compared with a 7 L leukapheresis volume.     

Leukapheresis after high-dose chemotherapy and autologous peripheral blood progenitor cell transplantation: a novel approach to harvest a second autograft

BACKGROUND: Autologous peripheral blood progenitor cells (PBPCs) are usually collected after the administration of conventional-dose chemotherapy (CDCT) and growth factors. However, there are no data available concerning the collection of PBPCs after high-dose chemotherapy (HDCT) and autologous hematopoietic transplantation in a larger series. STUDY DESIGN AND METHODS: Patients (n = 30) underwent leukapheresis for PBPC harvest after CDCT. After HDCT and autografting, the collection of a second PBPC autograft was attempted. RESULTS: Leukapheresis was performed after CDCT in all cases at a median of 118 CD34+ cells per microL (range, 18-589) and resulted in 6.4 x 10(6) CD34+ cells per kg (range, 1.7-29.0). After HDCT and autografting, 24 patients (80%) underwent secondary leukapheresis, although they had a significantly lower median of peripheral blood (PB) CD34+ cells (30/microL; range, 10-171; p < 0.001). In these patients a median of 3.6 x 10(6) CD34+ cells per kg (range, 1.6-10.1) was collected in the post-transplantation course. In the remaining six patients (20%) with PB CD34+ cells < 10 per microL, no PBPC harvesting was performed. These so-called poor mobilizers had received significantly less CD34+ cells for autologous transplantation than patients with successful post-HDCT mobilization (median, 2.5 x 10(6)/kg [range, 1.7-3.0] vs. 6.5 x 10(6)/kg [range, 3.2-19.6]; p < 0.001). CONCLUSION: Collection of PBPCs is possible in most patients during the recovery phase of hematopoiesis after HDCT plus autografting, and the number of circulating PBPCs may be related to the CD34+ cell dose transfused by the preceding autograft.     

Factors influencing mobilization and engraftment in patients with metastatic breast cancer undergoing PBSC transplantation.

Factors influencing mobilization and engraftment of PBSC were analyzed in 38 patients with metastatic breast cancer who were undergoing PBSC transplantation. None of these patients had had previous chemotherapy for metastatic disease. PBSC were mobilized with cyclophosphamide (CY) and G-CSF (n = 21) or CY and etoposide (CY-etoposide) and G-CSF (n = 17). All received cyclophosphamide 6000 mg/m2, thiotepa 500 mg/m2, and carboplatin 800 mg/m2 (CTCb) as preparative regimen. PBSC infusion was followed by G-CSF at 5 microg/kg in 30 patients or 10 microg/kg in 8 patients. A median number of 27 x 10(6) CD34+ cells/kg was obtained with a median of four aphereses. Previous chemotherapy, radiation therapy, marrow disease, time from previous chemotherapy to mobilization, and type of mobilization regimen did not have a statistically significant effect on collection efficiency (CE). CE was defined as the total number of CD34+ collected/number of collections. Engraftment was rapid, with patients reaching a neutrophil count of 0.5 x 10(9)/L a median of 9 days (range 7-23) and a platelet count of 20 x 10(9)/L a median of 12 days (range 8-28) after transplantation. Shorter times to platelet recovery were associated with a higher number of CD34+ cells infused (p = 0.012), CY mobilization (p = 0.033), and a lower number of prior chemotherapy cycles (p = 0.022). When the number of CD34+ cells was included in the proportional hazard model, no other variables were found to be significant predictors of platelet engraftment. Time to neutrophil recovery was negatively associated with the dose of G-CSF used after transplantation (p = 0.036) CD34 cell dose is an important predictor of engraftment kinetics. A posttransplant dose of G-CSF improves neutrophil recovery. For patients with metastatic breast cancer and no previous chemotherapy for metastatic disease, we have no evidence for a difference between CY and CY-Etoposide as the mobilization regimen.     

Harvesting of CD34 antigen-expressing cells with a new programme for the collection of mononuclear cells with use of the Amicus (Baxter) blood cell separator

A study was performed to evaluate a new programme for peripheral blood stem cell (PBSC) collection with the use of the Amicus (Baxter) blood cell separator. Healthy donors (n = 9) and oncology patients (n = 21) scheduled for PBSC transplant were studied. Ten PBSC harvests were performed in the donors and 30 in the patients. A median of 6.37 x 106 CD34+ cells per kg recipient body weight (range 3.08-11.06 x 106) were collected from the donors in a product weight of 169.5 g (118-186). From the patients, 6.26 x 106 CD34+ cells per kg body weight (range 0.2-53.6 x 106) were harvested in a product weighing 121.5 g (range 92-190). The median platelet contamination was 0.93 x 1011 (range 0.45-1.23 x 1011) per donor product and 0.2 x 1011 (range 0.05-0.86 x 1011) per patient product. No severe side effects were observed during or after the PBSC collection procedures.     

Comparison of progenitor cell collection on day 4 or day 5 after steady-state stimulation with G-CSF alone in breast cancer patients: influence on CD34+ cell yield, subpopulation, and breast cancer cell contamination

To determine the influence of apheresis timing on CD34+ cell yield, subpopulation, and breast cancer cell contamination, 48 women with breast cancer were stimulated from steady-state hematopoiesis in a prospective but nonrandomized study with 2 x 5 microg/kg G-CSF s.c. alone, and apheresis was started either on day 4 (n = 24) or day 5 (n = 24). Forty-eight women with breast cancer (stage II/III, n = 30; stage IV; n = 12; inflammatory, n = 6) and a median age of 44 years were well balanced between the two groups. In group I, aphersis was started on day 4 and additionally performed on day 5 after G-CSF stimulation, and in group II, apheresis was started on day 5. CD34+ cell count and CD34+ cell subpopulation were determined according to international criteria. Breast cancer cell contamination was detected by immunocytology. The median CD34+ cell harvest on day 4 was 3.3 x 10(6)/kg body weight (range 0.5-12.8) and 6 x 10(6)/kg BW (range 0.3-30) for patients starting on day 5 (p = 0.01). Those patients starting on day 4 achieved a median CD34+ cell count of 4 x 10(6)/kg (range 0.7-13) on day 5 (NS). Twenty-one percent of group I and 71% of group II achieved >5 x 10(6)/kg BW CD34+ cells in the first apheresis, whereas <2.5 x 10(6)/kg BW CD34+ cells in the first apheresis were observed in 38% of group I and 16% of group II. No differences were observed between the CD34+ cell subpopulations, CD34+/CD38+ (10.5% versus 10.5%) and CD34+/Thyl+ (1.5% versus 1.8%). The CD34+ cell harvest from consecutive collecting on days 4 and 5 was nearly identical to the harvest starting on day 5 (6.4 versus 6 x 10(6)/kg). Collecting CD34+ progenitor cells after stimulation with G-CSF alone on day 5 results in a significantly higher cell yield than starting collecting on day 4. No differences in respect to breast cancer cell contamination and CD34+ cell subpopulation were observed.     

Isolation of highly purified autologous and allogeneic peripheral CD34+ cells using the CliniMACS device.

The CliniMACS CD34+ selection device was used for positive selection of apheresis products for autologous transplantation from 10 patients with malignant diseases and for allogeneic transplantation from 26 healthy donors. A total of 71 separations were performed. In 1 allogeneic donor, CD34+ progenitors were also isolated from bone marrow. Between 0.27 and 8.9 x 10(10) nucleated cells (median 4.9 x 10(10)) containing 0.09%-10.8% (median 0.67%) CD34+ progenitor cells were separated. After separation, a median number of 227 x 10(6) mononuclear cells (MNC) (51-524) were recovered, with a median viability of 99% (22%-100%) and a median purity of 97.0% (68.3%-99.7%) CD34+ cells. Depletion of T cells was extensive, with a median of 0.04% residual CD3+ cells (range <0.01%-0.92%). Residual CD19+ cells were between <0.01% and 17%, including CD34+CD19+ cells. Recovery of CD34+ cells was calculated according to the ISHAGE guidelines and ranged from 24% to 105% (median 71%). We conclude that with the CliniMACS device CD34+ cells with high purity and recovery can be isolated with concomitant effective T cell depletion in the allogeneic setting and with a high purging efficacy in the autologous setting.     

Performance of a new separator system for routine autologous hematopoietic progenitor cell collection in small children

The AMICUS system was recently introduced for peripheral blood stem cell (PBSC) aphereses in adults. We conducted a single center field evaluation to obtain data about the performance of this system in children with a body weight (bw) < 25 kg. Results of blood priming procedures were compared to historical data obtained with the Fenwal CS3000+ (CS 3000). From August, 2001 to February, 2007, 47/178 (26%) PBSC aphereses procedures were performed in our institution with the AMICUS system in 35 small patients (median bw 13.9 kg; range 6.7-24; age 2.78 years; range 0.97-7.06). The patients suffered from various malignant primary diseases or recurrences. We primed the system with packed RBC in case of >30% dilution of the RBC volume (n = 31) or with saline (n = 16). Compared to the CS3000, the AMICUS revealed comparable collection efficiencies (CE) for CD34+ cells (median 67%, range 26-120), lymphocytes (75%, 25-138), monocytes (54%, 23-173), and granulocytes (10%, 1.5-36), MNC (57% 24-125), but a significantly higher erythrocyte and granulocyte, and a lower platelet CE. There was a significant negative correlation between total leukocyte count and CE for MNC (r = -0.566; P < 0.001) and CD34+ cells (r = -0.517; P < 0.001). There was no significant statistical or clinical difference between the CE in blood-primed procedures and saline-primed procedures. With the AMICUS we saw statistically less citrate reactions compared to the CS 3000. We conclude that the AMICUS system is safe and efficient to harvest PBSC on a routine basis in pediatric patients, even in children < or =10 kg bw.     

自体纯化CD34+细胞移植治疗严重自身免疫性疾病的初步研究

目的探讨自体外周血CD34+细胞移植治疗严重自身免疫性疾病的干细胞动员、细胞采集和分选、预处理和并发症处理等问题.方法 10例重度自身免疫性疾病患者接受自体外周血CD34+细胞移植治疗.采用环磷酰胺(CTX)+rhG-CSF方案动员外周血干细胞,并以CliniMACS细胞分选仪分选CD34+细胞,适时用CTX+抗胸腺细胞球蛋白(7例)或CTX+全身照射(3例)两种预处理方案后,进行CD34+细胞回输的方法治疗.结果经CTX+rhG-CSF方案动员并以CliniMACS细胞分选仪分选后,可获得(1.98±0.95)×108的CD34+细胞,其纯度为(91.4±10.6)%,回收率为(60.5±19.8)%.在回输(2.14±1.05)×106/kg的CD34+细胞后,ANC ≥0.5×109/L的时间为(8.6±2.5)d,血小板升至20×109/L的时间为(9.0±5.2)d.在造血恢复后,所有CD3+细胞、CD19+细胞和CD16+CD56+细胞均未恢复至移植前状态.在造血和免疫抑制时,巨细胞病毒感染的发生率较高.2例患者死于移植相关并发症.所有患者近期疗效满意,6例系统性红斑狼疮患者DAI评分由移植前的平均17分降为移植后的4分;类风湿关节炎患者DAS28评分由6.4分降至1.8分;干燥综合征患者的症状和体征均明显缓解.结论对常规治疗无效的严重自身免疫性疾病,自体外周血CD34+细胞移植是可选择的治疗方法之一.     

The impact of the CD34+ cell dose on engraftment in allogeneic peripheral blood stem cell transplantation

Forty-five patients who underwent allogeneic peripheral blood stem cell transplantation (PBSCT) were evaluated in order to investigate any relationship between CD34+ cell dose given and hematological recovery. Granulocyte counts > 1.0 x 10(9)/L and platelet > 50 x 10(9)/L were considered as hematological recovery. Three different regimens were used for mobilization, by adjusting the recombinant granulocyte colony stimulating factor (rhG-CSF, Roche) dose. The first group (n = 3), whose donors mobilized with 5 micrograms/kg/d s.c. rhG-CSF received a mean of 5.9 x 10(6)/kg (95% confidence interval for mean (CI); 2.4-9.3) CD34+ cells. The second group (n = 37), mobilized with 10 micrograms/kg/d s.c. rhG-CSF and the third group (n = 5) mobilized with 15 micrograms/kg/d s.c. rhG-CSF, received a mean of 5.7 x 10(6)/kg (95% CI; 4.6-6.75) and 6.56 x 10(6)/kg (95% CI; 4.57-8.55) CD34+ cells, respectively. CD34+ cell dose was 5.82 x 10(6)/kg (95% CI; 4.97-6.68) for all the patients. All patients received rhG-CSF from day +1 until attaining granulocyte count > 1.0 x 10(9)/L for three consecutive days. Median granulocyte and platelet engraftment days for the whole group was 15 (range; 11-44) and 14 (11-54) days respectively. There was a close correlation (r = -0.301, p < 0.05) between the CD34+ cell dose and granulocyte recovery for the whole group. When these analyses were performed separately within groups, this correlation was also found significant for the first group (r = -0.99, p < 0.05) for granulocyte recovery. On the contrary the same analysis did not reach significance for the other groups, nor for platelet recovery for the whole group (r = 0.039, p = 0.821). We calculated a minimum dose of 4 x 10(6)/kg CD34+ cells for a safe alloPBSCT. There was no difference between patients who received more than 5 x 10(6)/kg CD34+ cells, and those who received more than 2 x 10(6)/kg and less than 5 x 10(6)/kg CD34+ cells. In conclusion, we have demonstrated a correlation between the CD34+ cell dose given and faster hematological recovery for alloPBSCT patients.     

Immune reconstitution after autologous selected peripheral blood progenitor cell transplantation: comparison of two CD34+ cell-selection systems

BACKGROUND: Selection of CD34+ PBPCs has been applied as a method of reducing graft contamination from neoplastic cells. This procedure seems to delay lymphocyte recovery, while myeloid engraftment is no different from that with unselected PBPC transplants. STUDY DESIGN AND METHODS: Lymphocyte recovery was studied in two groups of patients who underwent autologous CD34+ PBPC transplant with two different technologies (Ceprate SC, Cellpro [n = 17]; CliniMACS, Miltenyi Biotech [n = 13]). The median number of CD34+ cells transfused was 3.88 x 10(6) per kg and 3.32 x 10(6) per kg, respectively. Residual CD3 cells x 10(6) per kg were 4.97 and 0.58, respectively (p = 0.041). Residual CD19 cells x 10(6) per kg were 1.33 and 0.73, respectively (NS). RESULTS: No differences were found between the two groups in total lymphocyte recovery to >0.5 x 10(9) per L, which achieved a stable count by Day 30. During the study period, the CD4+ cell count remained below 0.2 x 10(9) per L, and the B-cell subset showed a trend toward normalization. CD3/HLA-DR+ and CD16/56 increased markedly in both groups by Day 30. An increase in CMV (13%) and adenovirus (17.4%) infection was found in both groups. CONCLUSION: Both CD34+ cell selection technologies used here determined an excellent CD34+ cell purity and an optimal depletion of T cells. The high rate of viral complications is probably due to the inability of residual T cells left from the CD34+ cell selection to generate, immediately after transplant, an adequate number of virus-specific lymphocytes.     

A controlled comparison of two different clinical grade devices for CD34+ cell selection of autologous blood stem cell grafts

Six patients who were to undergo autologous PBSC transplantation with positively selected CD34+ cells were included in this study to compare the efficiency of two devices for clinical grade stem cell selection, the Isolex 300i (Baxter, Munich, Germany) and CEPRATE SC (CellPro, Bothell, WA). PBSC were mobilized by chemotherapy and G-CSF and were collected by leukapheresis on a CS3000 cell separator on 2 consecutive days. The two apheresis products were pooled for CD34 selection. The pooled apheresis products from each patient were divided into two equal portions to be separated on each of the two devices. Cell selection was performed according to the manufacturers' instructions. Enumeration of CD34+ cells was performed by flow cytometry using the HPCA-2 MAb. Purity and yield were significantly better with Isolex than with CEPRATE. Median purity was 93.0% (range 80%-98%) for Isolex and 61.5% (range 27%-72%) for CEPRATE (p = 0.03); median yields for Isolex and for CEPRATE were 48.0% (range 18%-73%) and 23.0% (range 17%-29%), respectively (p = 0.03). The number of CD34+ cells/kg body weight was also significantly higher with Isolex (median 3.8x10(6), range 1.7-5.2) compared with CEPRATE (median 2.35x10(6), range 0.7-4.3) (p = 0.03). Thus, the Isolex 300i device gave products of higher purity and recovered a higher proportion of the CD34+ cells in the harvest before separation. The yield was still poor with both devices, however, and further optimization of the technique for clinical grade stem cell selection is warranted.     

CD34+ cell dose requirements for rapid engraftment in a sequential high-dose chemotherapy regimen of paclitaxel, melphalan, and cyclophosphamide, thiotepa, and carboplatin (CTCb) with PBPC support in metastatic breast cancer

Sequential high-dose chemotherapy may increase the threshold dose of CD34+ cells necessary for rapid and successful hematologic recovery. There are limited data regarding the pharmacodynamics and threshold CD34+ cell dose required for engraftment following high-dose paclitaxel. To determine the dose of CD34+ PBPC sufficient for rapid engraftment, 65 women with metastatic breast cancer undergoing a sequential high-dose paclitaxel, melphalan, and cyclophosphamide, thiotepa, and carboplatin (CTCb) chemotherapy regimen were evaluated. The intertreatment interval was a median of 27 days. Paclitaxel was escalated from 400 to 825 mg/m2, infused continuously (CI) over 24 h on day -4 with PBPC reinfusion on day 0. Following marrow recovery, 90 mg/m2/day of melphalan was given over 30 min on days -2 and -1, with PBPC reinfusion on day 0. On recovery, patients received CTCb on days -7 to -3, with PBPC reinfusion on day 0. G-CSF was administered after each cycle until WBCC recovery. For paclitaxel, an ANC >0.5 x 10(9)/L occurred at a median of 6 days (range 0-7 days) after PBPC reinfusion. The median nadir platelet count was 63 x 10(9)/L (range 6 x 10(9)/L-176 x 10(9)/L). Eight patients (12%) had platelet nadir <20 x 10(9)/L, and all recovered their counts to >20 x 10(9)/L on day 7. There was no clinical difference in days to engraftment between women receiving <2 or > or =2 x 10(6) CD34+ PBPC/kg following paclitaxel. All patients recovered neutrophil and platelet counts within 7 days after reinfusion of > or =1 x 10(6) CD34+ cells/kg and G-CSF. The data suggest that a paclitaxel dose of 825 mg/m2 is not myeloablative. For melphalan, median days to ANC >0.5 x 10(9)/L was 10 days (range 9-15), and platelet recovery to >20 x 10(9)/L was 13 days (range 0-28) after PBPC reinfusion. Median time to engraftment was more rapid in patients receiving > or =2 x 10(6) CD34+/kg versus <2 x 10(6)CD34+/kg, for both neutrophils (11 days versus 10 days, p = 0.05) and platelets (14 days versus 12 days, p < 0.01). Ninety-eight percent of patients infused with > or =2 x 10(6) CD34+/kg engrafted within 21 days. Following CTCb in this sequential regimen, a dose of > or =2 x 10(6) CD34+ cells/kg provided for significantly more rapid neutrophil engraftment than <2 x 10(6) CD34+ cells/kg (9 days versus 10 days,p = 0.01), but a dose > or =3 X 10(6) CD34+ cells/kg is necessary for reliable, rapid, and sustained neutrophil and platelet engraftment by day 21.     

Differential effects of IL-2 incubation on hematopoietic potential of autologous bone marrow and mobilized PBSC from patients with hematologic malignancies

Culturing of hematopoietic progenitor cells for 24 h with IL-2 generates cytotoxic effector cells that mediate in vitro and possibly in vivo antitumor activity. We examined the effect of IL-2 incubation on progenitor cells from 24 patients with hematologic malignancies using paired autologous bone marrow (ABM) and PBSC to determine differences in hematopoietic potential. Cells were cryopreserved and stored in liquid nitrogen until conditioning therapy was completed. After thawing, cells were incubated with IL-2 for 24 h at 37 degrees C. Paired samples of ABM and PBSC from the same patient were analyzed for nucleated and mononuclear cell number, CD34 antigen expression, and colony-forming unit (CFU) activity before and after IL-2 incubation. There was a significant decrease in the average number of mononuclear cells (MNC) (x10(8)/kg) (<0.001) and CD34+ cells (x10(6)/kg) (0.006) from both ABM and PBSC after 24 h IL-2 culture (ABM MNC: 0.6+/-0.1 vs. 0.4+/-0.0, p = <0.001; PBSC MNC: 4.4+/-0.5 vs. 3.7+/-0.4, p = 0.03; ABM CD34+: 2.4+/-0.5 vs. 1.3+/-0.3, p = <0.001; PBSC CD34+: 6.6+/-1.8 vs. 5.0+/-1.2, p = 0.05). However, whereas ABM CFU/10(5) MNC plated (269.3+/-47.2 vs. 385.6+/-70.6) were significantly increased (p = 0.005), there was no change in PBSC CFU (271.0+/-47.2 vs. 257.3+/-48.5). The mean plating efficiency (%) of ABM CD34+ cells was markedly increased after IL-2 incubation (10.1+/-3.3 vs. 19.0+/-7.2, p = 0.04), although it was lower than that of PBSC CD34+ cells, which did not change significantly in culture (29.4+/-5.5 vs. 36.0+/-6.5). Additional work is in progress to determine the cause and significance of the enhanced plating efficiency of the ABM progenitor cells.     

Peripheral blood stem cell collection from healthy donors for allogeneic transplantation

There is great interest in the use of peripheral blood stem cells (PBSC) for allogeneic transplantation, based on the good results seen with autologous PBSC infusion. Reasonable caution exists regarding the use of allogeneic PBSC for transplantation because of donor toxicities due to rhG-CSF administration and the risk of graft-versus-host-disease (GVHD) in the recipient because of the large number of T-cell infused. We present preliminary data on allogeneic PBSC collections and transplantation in ten patients affected by advanced leukemia (eight patients), severe aplastic anemia (one patient) and sickle cell anemia (one patient). Seven donors were HLA-identical siblings, while the other three were mismatched for three, two and one locus, respectively. All donors received rhG-CSF at a dose of 12 micrograms/kg for a mean of 5 days. Leukaphereses were performed with the aim of collecting a minimum of 5 x 10(6)/kg (recipient's weight) CD 34+ cells. Collection timing was determined by monitoring CD 34+ cells in the donor's peripheral blood from the second day of rhG-CSF therapy. The PBSC collections yielded a mean of 10.05 x 10(8) MNCs/kg and of 10.48 x 10(6) CD 34+ cells/kg (recipient's weight). PBSC were immediately infused after collection in patients given myeloablative therapy. Engraftment was observed in each patient at a mean of 13.2 days for an absolute neutrophil count (ANC) more than 0.5 x 10(9)/L and of 26.5 days for a platelet count of more than 20 x 10(9)/L. Eight patients experienced no or moderate acute GVHD, whereas two patients died of grade 4 GVHD, notwithstanding GVHD prophylaxis with cyclosporine and prednisone. Two other patients died of viral and fungal infections, respectively, despite prophylaxis. The remaining six patients are alive between 58 and 430 days after transplant. Our results document that allogeneic PBSC are capable of engraftment after a myeloablative regimen. Controlled trials are necessary to compare the potential benefits of this approach with the results obtained in allogeneic bone marrow transplantation.     

Peripheral blood stem cell mobilization for high-dose chemotherapy.

Several studies have clearly documented a more rapid hematopoietic recovery with growth factor-mobilized PBSC than with bone marrow. Time to engraftment for neutrophils and platelets average 8-12 days in contrast to 2-4 weeks after bone marrow. This rapid hematopoietic recovery with PBSC has decreased the duration of hospitalization, transfusion requirements, and costs. Although growth factors alone may mobilize enough PBSC for high-dose chemotherapy, administration of growth factor after submyeloablative chemotherapy increases the yield of CD34+ cells. Based on the current data, CD34+ cell content of PBSC appears to be the single most powerful predictor of hematopoietic recovery. Infusion of > or =5 x 10(6) CD34+ cells/kg is associated with a rapid engraftment of neutrophils and platelets, although successful engraftment has also been reported with infusion of 2.5-5 x 10(6) CD34+ cells/kg. Age, prior radiotherapy, marrow involvement, and prior chemotherapy regimens are important factors influencing the yield of stem cells. Therefore, using these pa-rameters, we may identify the patients who will fail to mobilize sufficient numbers of PBSC before collection and use new strategies for stem cell mobilization. Because of the ease of collection and rapid engraftment after myeloablative therapy, PBSC have replaced bone marrow for autologous transplantation and may supplant bone marrow for allogeneic transplantation in the near future.     

The absolute number of peripheral blood CD34+ cells predicts a timing for apheresis and progenitor cell yield in patients with hematologic malignancies and solid tumors

Retrospective analysis was conducted in 51 autologous peripheral blood progenitor cell (PBPC) collections using the Spectra AutoPBSC System from patients with hematologic malignancies and solid tumors to study the predictive value of CD34+ cell counts in the peripheral blood for the yield of CD34+ cells in the apheresis product. The correlation coefficients for CD34+ cells microL(-1) of peripheral blood with CD34+ cell yield (x 10(6) kg(-1) of body weight and x 10(5) kg(-1) of body weight L(-1) of blood processed) were 0.903 and 0.778 (n=51 collections), respectively. Products collected from patients with CD34+ cell counts below 15 microL(-1) in the peripheral blood contained a median of 0.49 x 10(6) CD34+ cells kg(-1) (range: 0.05-2.55), whereas those with CD34+ cell counts more than 15 microL(-1) contained a median of 3.72 x 10(6) CD34+ cells kg(-1) (range: 1.06-37.57). From these results, a number of at least 15 CD34+ cells microL(-1) in the peripheral blood ensured a minimum yield of 1 x 10(6) CD34+ cells kg(-1) as obtained by a single apheresis procedure. The number of CD34+ cells in the peripheral blood can be used as a good predictor for timing of apheresis and estimating PBPC yield. With regard to our results, apheresis with a possibly poor efficiency should be avoided because the collection procedure is time-consuming and expensive.     

Peripheral blood stem cell collection and transplantation using the Haemonetics Multi Component System

AIM: To assess clinical usefulness of an intermittent-flow blood cell separator in peripheral blood stem cell (PBSC) collection and transplantation. RESULTS: The Haemonetics Multi Component System (Multi) was used to collect PBSC (52 aphereses in 17 patients). The mean processing blood volume and the mean PBSC yield were 7407 ml and 2.16 x 10(6) CD34+ cells/kg, respectively. When CD34+ cells exceeded 0.3% of the peripheral WBC, more than 2.0 x 10(6) CD34+ cells/kg could be collected by a single apheresis. Eight patients underwent PBSC transplantation after high-dose chemotherapy. Hematopoietic recovery was achieved in a median period of 10 days. CONCLUSIONS: (1) A single-arm, light-weight machine has sufficient capability to collect PBSC. (2) The percentage of CD34+ cells in the peripheral WBC is a good predictor of the CD34+ cell yield of the collection.     

短程大剂量粒细胞集落刺激因子动员外周血造血干细胞的研究

研究短程大剂量粒细胞集落刺激因子对外周血造血干细胞的动员作用。方法采用短程大剂量Ｇ－ＣＳＦ对１１例患者进行外周血造血干细胞动员，Ｇ－ＣＳＦ５μｇ／ｋｇ皮下注射，每日２次，共３天，动员当天及第４天，分别取骨髓及外周血增生明显活跃，外周血白细胞计数明显升高。     

Rapid and effective CD3 T-cell depletion with a magnetic cell sorting program to produce peripheral blood progenitor cell products for haploidentical transplantation in children and adults

BACKGROUND: Effective T-cell depletion is a prerequisite for haploidentical peripheral blood progenitor cell (PBPC) transplantation. This study was performed to investigate the performance of magnetic cell sorting-based direct large-scale T-cell depletion, which is an attractive alternative to standard PBPC enrichment procedures. STUDY DESIGN AND METHODS: PBPCs were harvested from 11 human leukocyte antigen (HLA)-haploidentical donors. T cells labeled with anti-CD3-coated beads were depleted with a commercially available magnetic separation unit (CliniMACS, Miltenyi Biotec) with either the Depletion 2.1 (D2.1, n=11) or the novel Depletion 3.1 (D3.1, n=12) program. If indicated, additional CD34+ selections were performed (n=6). Eleven patients received T-cell-depleted grafts after reduced-intensity conditioning. RESULTS: The median log T-cell depletion was better with the D2.1 compared to the D3.1 (log 3.6 vs. log 2.3, p<0.05) and was further improved by introducing an immunoglobulin G (IgG)-blocking step (log 4.5 and log 3.4, respectively). The D3.1 was superior to the D2.1 (p<0.05) in median recovery of CD34+ cells (90% vs. 78%) and in median recovery of CD3- cells (87% vs. 76%). The median processing times per 10(10) total cells were 0.90 hours (D2.1) and 0.35 hours (D3.1). The transplanted grafts (directly T-cell-depleted products with or without positively selected CD34+ cells) contained a median of 10.5 x 10(6) per kg CD34+, 0.93x10(5) per kg CD3+, and 11.6x10(6) per kg CD56+. Rapid engraftment was achieved in 10 patients. The incidences of acute graft-versus-host disease were less than 10 percent (Grade I/II) and 0 percent (Grade III/IV). CONCLUSION: The novel D3.1 program with IgG blocking enables highly effective, time-saving large-scale T-cell depletion. Combining direct depletion techniques with standard CD34+ selection enables the composition of grafts optimized to the specific requirements of the patients.