The predictive value of white cell or CD34+ cell count in the peripheral blood for timing apheresis and maximizing yield

BACKGROUND: The collection of peripheral blood stem and progenitor cells (PBPCs) for transplantation can be time-consuming and expensive. Thus, the utility of counting CD34+ cells and white cells (WBCs) in the peripheral blood was evaluated as a predictor of CD34+ cell yield in the apheresis component. STUDY DESIGN AND METHODS: The WBC and CD34+ cell counts in the peripheral blood and the apheresis components from 216 collections were assessed. Sixty-three patients underwent mobilization with chemotherapy plus filgrastim, and 17 patients and 14 allogeneic PBPC donors did so with filgrastim alone. The relationship between the number of WBC and CD34+ cells in the peripheral blood and in the apheresis component was analyzed by using rank correlation and linear regression analysis. RESULTS: The correlation coefficient for CD34+ cells per liter of peripheral blood with CD34+ cell yield (x 10(6)/kg) was 0.87 (n = 216 collections). This correlation existed for many patient and collection variables. However, patients with acute myeloid leukemia had fewer CD34+ cells in the apheresis component at any level of peripheral blood CD34+ cell count. Components collected from patients with CD34+ cell counts below 10 x 10(6) per L in the peripheral blood contained a median of 0.75 x 10(6) CD34+ cells per kg. When the WBC count in the blood was below 5.0 x 10(9) per L, the median number of CD34+ cells in the peripheral blood was 5.6 x 10(6) per L (range, 1.0-15.5 x 10(6)/L). A very poor correlation was found between the WBC count in the blood and the CD34+ cell yield (p = 0.12, n = 158 collections). CONCLUSION: The number of CD34+ cells, but not WBCs, in the peripheral blood can be used as a predictor for timing of apheresis and estimating PBPC yield. This is a robust relationship not affected by a variety of patient and collection factors except the diagnosis of acute myeloid leukemia. Patients who undergo mobilization with chemotherapy and filgrastim also should undergo monitoring of peripheral blood CD34+ cell counts, beginning when the WBC count in the blood exceeds 1.0 to 5.0 x 10(9) per L.     

CD34+ cell mobilization for allogeneic progenitor cell transplantation: efficacy of a short course of G-CSF

BACKGROUND: G-CSF-mobilized PBPCs are considered the richest source of HPCs for both autologous and allogeneic transplantation, but, despite their wide use, the best dose and schedule for G-CSF administration have not been definitively established. STUDY DESIGN AND METHODS: With a target of collecting from the peripheral blood > or = 4 x 10(6) CD34+ cells per kg of body weight of the recipient, the short-course administration of glycosylated G-CSF (gly-G-CSF) in 30 healthy donors for an allogeneic transplantation was investigated. Gly-G-CSF was given subcutaneously at a dose of 10 microg per kg per day in two divided doses over 3 days and was followed by a leukapheresis (on the 4th day) 12 hours after the last dose. RESULTS: A median of 53.5 circulating CD34+ cells per microL (range, 19-190) was found in the 30 donors on the day of first leukapheresis, which allowed a median CD34+ cell collection of 6.0 x 10(6) per kg of body weight of the donor and 6.5 x 10(6) per kg of body weight of the recipient. In 25 (83%) of 30 donors, a single procedure was sufficient to collect the target CD34+ cells, while in the other 5, two leukapheresis procedures were required. Hematologic reconstitution was observed in all patients at a median of 14 days (range, 10-23) for neutrophils and 14.5 days (range, 11-46) for platelets. With a median infusion of 3.9 x 10(8) CD3+ T-lymphocytes per kg of body weight of the recipient (range, 1.3-7.8), acute and chronic GVHD occurred in 13 (43%) of 30 and 15 (60%) of 25 evaluable patients, respectively. After a median follow-up of 337 days from transplant, 22 (73%) of 30 patients are alive in complete remission. CONCLUSION: A schedule consisting of 3-day administration of gly-G-CSF followed by a single leukapheresis can be proposed and widely accepted by healthy donors, as 84 percent of them reach the target in the estimated time with a reduced drug exposure. The cost of the procedure is reduced, in terms of both the growth factor administration and the number of leukapheresis procedures. The search for the optimum methods of donor management may improve the acceptability of this procedure and increase the number of allogeneic transplantations from PBPCs.     

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.     

Uncontrolled-rate freezing and storage at -80 degrees C, with only 3.5-percent DMSO in cryoprotective solution for 109 autologous peripheral blood progenitor cell transplantations

BACKGROUND: Although controlled-rate freezing and storage in liquid nitrogen are the standard procedure for peripheral blood progenitor cell (PBPC) cryopreservation, uncontrolled-rate freezing and storage at -80 degrees C have been reported. STUDY DESIGN AND METHODS: The prospective evaluation of 109 autologous PBPC transplantations after uncontrolled-rate freezing and storage at -80 degrees C of apheresis products is reported. The cryoprotectant solution contained final concentrations of 1-percent human serum albumin, 2.5-percent hydroxyethyl starch, and 3.5-percent DMSO. RESULTS: With in vitro assays, the median recoveries of nucleated cells (NCs), CD34+ cells, CFU-GM, and BFU-E were 60.8 percent (range, 11.2-107.1%), 79.6 percent (6.3-158.1%), 35.6 percent (0.3-149.5%), and 32.6 percent (1.7-151.1%), respectively. The median length of storage was 7 weeks (range, 1-98). The median cell dose, per kg of body weight, given to patients after the preparative regimen was 6.34 x 10(8) NCs (range, 0.02-38.3), 3.77 x 10(6) CD34+ cells (0.23-58.5), and 66.04 x 10(4) CFU-GM (1.38-405.7). The median time to reach 0.5 x 10(9) granulocytes per L, 20 x 10(9) platelets per L, and 50 x 10(9) reticulocytes per L was 11 (range, 0-37), 11 (0-129), and 17 (0-200) days, respectively. Hematopoietic reconstitution did not differ in patients undergoing myeloablative or nonmyeloablative conditioning regimens before transplantation. CONCLUSION: This simple and less expensive cryopreservation procedure can produce successful engraftment, comparable to that obtained with the standard storage procedure.     

Collection of peripheral blood progenitor cells with an automated leukapheresis system

BACKGROUND: Apheresis devices designed for the collection of mature blood elements are being used for the collection of peripheral blood progenitor cells (PBPCs).The collection of PBPCs differs from that of other cells in the rarity of the target cell and in the fact that donors may undergo several days of collection. A consequence of this process may be a depletion of blood cells such as platelets from the blood. The disposable set and operating software for an apheresis device (Spectra, COBE BCT) was modified by the manufacturer to automate the collection of PBPCs and reduce the collection of unwanted blood cells. STUDY DESIGN AND METHODS: A study was initiated to compare the collection of PBPCs with the new device, the AutoPBSC (version [V]6.0 with AutoPBSC tubing set), and that with the MNC (mononuclear cell) procedure (V4.7 with white cell tubing set), for patients and healthy donors. RESULTS: Patients whose blood was processed by either theV6.0 orV4.7 procedure achieved the target dose of 5 x 10(6) CD34+ cells per kg of patient weight in similar numbers of procedures, even though the calculated collection efficiency for CD34+ cells using the automated V6.0 procedure was significantly less than that with the V4.7 procedure for both allogeneic donors and patients donating PBPCs. The collection efficiency for platelets was lower with the V6.0 procedure, and components collected in this manner contained fewer platelets. Apheresis by the V6.0 procedure required 30 to 60 more minutes per procedure than apheresis by the V4.7 procedure. Review of engraftment kinetics after transplantation did not reveal any effect of the collection procedure on recipients of either allogeneic or autologous transplants. CONCLUSION: The collection efficiencies of the V6.0 procedure for both CD34+ cells and mature blood cells are lower than those of the V4.7 procedure.The lower collection efficiency for platelets results in a smaller drop in peripheral blood platelet count after the procedure.The automated features of the V6.0 procedure may simplify PBPC collection, but this procedure requires a longer apheresis.     

PBPC mobilization with paclitaxel, ifosfamide, and G-CSF with or without amifostine: results of a prospective randomized trial

BACKGROUND: The impact of amifostine on PBPC mobilization with paclitaxel and ifosfamide plus G-CSF was assessed. STUDY DESIGN AND METHODS: Forty patients with a median age of 34 years (range, 19-53) who had germ cell tumor were evaluated for high-dose chemotherapy. Patients were randomly assigned to receive either a single 500-mg dose of amifostine (Group A, n = 20) or no amifostine (Group B, n = 20) before mobilization chemotherapy with paclitaxel (175 mg/m(2)) given over 3 hours and ifosfamide (5 g/m(2)) given over 24 hours (TI) on Day 1. G-CSF at 10 microg per kg per day was given subsequent to TI with or without amifostine from Day 3 until the end of leukapheresis procedures. RESULTS: In 2 (10%) of 20 patients receiving amifostine and 3 (15%) of 20 patients not receiving it, no PBPC separation was performed because of mobilization failure. No significant differences were observed in the study arms with regard to the time from chemotherapy until first PBPC collection or the number of apheresis procedures needed to harvest more than 2.5 x 10(6) CD34+ cells per kg. Furthermore, leukapheresis procedures yielded comparable doses of CD34+ cells per kg (3.4 x 10(6) vs. 3.6 x 10(6); p = 0.82), MNCs per kg (2.7 x 10(8) vs. 2.6 x 10(8); p = 0.18), and CFU-GM per kg (15.9 x 10(4) vs. 19.3 x 10(4); p = 0.20). Patients in Group A had higher numbers of circulating CD34+ cells on Day 10 (103.0/microL vs. 46.8/microL; p = 0.10) and on Day 11 (63.0/microL vs.14.3/microL; p = 0.04) than did patients in Group B. CONCLUSION: Administration of a single dose of amifostine before chemotherapy with TI mobilized higher numbers of CD34 cells in the circulation, but did not enhance the overall collection efficiency in the present trial.     

High platelet contamination in progenitor cell concentrates results in significantly lower CD34+ yield after immunoselection

BACKGROUND: Selection of CD34+ cells by specific immunoselection leads to a significant loss of those cells. The factors influencing the yield and purity are not well identified. The results of CD34+ selection from peripheral blood progenitor cells (PBPCs) with high and low platelet contamination that are harvested with two different cell separators are reported. STUDY DESIGN AND METHODS: A progenitor cell concentrator (Ceprate SC, CellPro) was used to select CD34+ cells from 41 PBPC concentrates from 23 consecutive patients with relapsed non-Hodgkin's lymphoma (n = 3), breast cancer (n = 17), and multiple myeloma (n = 3). PBPC collection was performed by using two cell separators (CS3000 Plus, Fenwal: Group A, n = 11; and Spectra, COBE: Group B, n = 9). To reduce platelet contamination in the Spectra PBPC concentrates, an additional low-speed centrifugation was performed before CD34+ cell selection (Group C, n = 3). Leukapheresis components were stored overnight at 4 degrees C and combined with the next day's collection before the CD34+ selection procedure in 19 patients. RESULTS: A median of 1.5 leukapheresis procedures per patient were performed. Pooled PBPC concentrates showed no statistical difference in median numbers of white cells and CD34+ cells in Groups A and B: 3.2 (0.8-9.2) versus 4.4 (1.6-8. 3) x 10(10) white cells per kg and 15.0 (4.7-24.0) versus 12.0 (5. 6-34.0) x 10(6) CD34+ cells per kg. Platelet contamination was significantly higher in Group B: 0.67 (0.15-2.4) versus 2.3 (0.5-7. 1) x 10(11) (p = 0.0273). After the selection process, there was a significantly greater loss of CD34+ cells in Group B than in Group A: 39.1 versus 63.2 percent (p = 0.0070), with a median purity of 78. 0 percent versus 81.0 percent. An additional low-speed centrifugation before CD34+ cell selection seemed to reduce CD34+ cell loss in Group C with 16.9, 31.9, and 37.5 percent, respectively. CONCLUSION: CD34+ cell selection from PBPC concentrates resulted in an increased loss of CD34+ cells in concentrates with a higher platelet content. To improve CD34+ yield, PBPC concentrates with an initially low platelet contamination should be used, or additional low-speed centrifugation should be performed.     

Kinetics of PBPC mobilization by cyclophosphamide, as compared with that by epirubicin/paclitaxel followed by G-CSF support: implications for optimal timing of PBPC harvest

BACKGROUND: Limited information is available on the mobilization kinetics of autologous PBPCs after induction with various chemotherapy regimens. With PBPC mobilization in patients with breast cancer used as a model for chemotherapy-induced PBPC recruitment, the kinetics of progenitor cells mobilized either with cyclophosphamide (CY) or epirubicin/paclitaxel (EPI-TAX) followed by the administration of G-CSF was compared. STUDY DESIGN AND METHODS: The study included a total of 86 patients with breast cancer (stage II-IV) receiving either CY (n = 39) or EPI-TAX (n = 47), both followed by G-CSF support. The progenitor cell content in peripheral blood and apheresis components was monitored by flow cytometric enumeration of CD34+ cells. PBPC collection was started when the threshold of >20 x 10(6) CD34+ cells per L of peripheral blood was reached. RESULTS: The PBPC collection was begun a median of 9 days after the administration of EPI-TAX followed by G-CSF support, as compared to a median of 13 days after mobilization with CY plus G-CSF. After treatment with CY, the total numbers of PBPCs peaked on Day 1 of apheresis, and they rapidly declined thereafter. In contrast, treatment with EPI-TAX followed by G-CSF administration led to a steady mobilization of CD34+ cells during leukapheresis. The difference in the mobilization patterns with CY and EPI-TAX resulted in a greater yield of CD34+ cells per L of processed blood volume. Compared to EPI-TAX, mobilization with CY required the overall processing of 30 percent less whole-blood volume to reach the target yield of > or = 10 x 10(6) CD34+ cells per kg of body weight. After a median of three apheresis procedures, however, both CY+G-CSF and EPI-TAX+G-CSF were equally effective in obtaining this target yield. CONCLUSION: These results imply that specific PBPC mobilization as part of a given chemotherapy regimen should be taken into consideration before the planning of a PBPC harvest.     

The timing of granulocyte–colony-stimulating factor administration after chemotherapy does not affect stem and progenitor cell apheresis yield: a retrospective study of 65 cases

BACKGROUND: The optimal time for postchemotherapy granulocyte-colony stimulating factor (G-CSF) administration before peripheral blood stem and progenitor cell (PBPC) collection is not well defined. The impact of G-CSF scheduling on the number of CD34+ cells collected by leukapheresis from 65 patients with malignant disease was studied retrospectively. STUDY DESIGN AND METHODS: Chemotherapy was performed on Days 1 and 2 and was followed by G-CSF to mobilize PBPCs. In Group 1, 30 patients received the first dose of G-CSF immediately after the end of chemotherapy, as commonly recommended. In Group 2, 35 patients received the first G-CSF dose after the end of chemotherapy (Days 7 or 8). RESULTS: No difference was observed between the two groups in white cell recovery and the median number of CD34+ cells harvested. The number of leukapheresis procedures necessary to obtain the minimal number of 3 x 10(6) CD34+ cells per kg was the same. The proportion of patients with a failure of PBPC collection was similar, and G-CSF consumption was reduced in Group 2 without increasing infectious risks. CONCLUSION: Early administration of G-CSF after chemotherapy appears not to be a prerequisite for satisfactory PBPC collection. This approach could allow significant savings in terms of medical cost. A randomized and prospective study would be necessary, however, to assess the validity of these conclusions.     

The dose of granulocyte-colony-stimulating factor after chemopriming treatment does not influence apheresis yield of progenitor cells: a retrospective study of 91 cases

BACKGROUND: The optimal dose of post-chemotherapy granulocyte-colony-stimulating factor (G-CSF) administration before peripheral blood progenitor cell (PBPC) collection has not been determined as yet, although 5 microg per kg per day has been recommended as the standard dose. This study retrospectively analyzed the effect of G-CSF dose on peripheral blood CD34+ cell collection from 91 patients with hematologic malignancies. STUDY DESIGN AND METHODS: Various doses of G-CSF were administered after several chemotherapeutic PBPC mobilization regimens. According to the dose of G-CSF administered, patients were assigned to two groups. Group 1 included 46 patients who received a low dose of G-CSF (median, 3.6 [range, 2.8-4.6] microg/kg/day). Group 2 included 45 patients who received a standard G-CSF dose of 6.0 (5.5-8. 1) microg per kg per day. Patients in the two groups were matched for age, diagnosis, previous therapy, and chemotherapeutic PBPC mobilization regimens. RESULTS: No difference was observed in the median number of CD34+ cells harvested from each group.The number of leukapheresis procedures necessary to obtain a minimum of 3 x 10(6) CD34+ cells per kg was the same in both groups, and the percentage of patients who failed to achieve adequate PBPC collections was similar in the two groups. CONCLUSION: The administration of low-dose G-CSF after chemotherapy appears equivalent to administration of the standard dose in achieving satisfactory PBPC collection.This approach could allow significant savings in medical cost. A randomized and prospective study is necessary, however, to assess the validity of these conclusions.     

Leukapheresis components may be cryopreserved at high cell concentrations without additional loss of HPC function

BACKGROUND: The aim of this study was to assess the feasibility of freezing mobilized peripheral blood progenitor cell (PBPC) components at higher cell concentrations than are classically recommended for bone marrow. This approach might have potential benefits, such as lower cost of processing and storage and less risk of the complications associated with the transfusion of large component volumes and large quantities of DMSO. STUDY DESIGN AND METHODS: In the first phase, small aliquots of 19 apheresis components were cryopreserved at standard and higher cell concentrations (Aliquots A and B, respectively). In the second phase, 21 apheresis components were split into two bags each and frozen at standard (Bag A) and high (Bag B) cell concentrations. The differences in viability, cloning efficiency, and nucleated cell recovery in Bags A and B were examined. Finally, the hematologic recovery of 10 patients who underwent autologous transplantation with PBPC components frozen at high cell concentrations was analyzed. RESULTS: The median cell concentration at freezing was 94 (57-100) x 10(6) per mL and 291 (220-467) x 10(6) per mL for Aliquots A and B, respectively, and 90.9 (45.4-92) x 10(6) per mL and 332 (171-582) x 10(6) per mL for Bags A and B, respectively. The viability was significantly lower in samples frozen at higher cell concentrations: 92 versus 83 percent (p = 0.001) and 87 versus 77 percent (p<0.001) for Aliquots and Bags A and B, respectively. Significant differences were not observed in the recovery of total nucleated cells (102 vs. 101% and 98 vs. 105%) or the cloning efficiency after thawing (13 vs. 16% and 27 vs. 23%) for Aliquots and Bags A and B, respectively. The time to granulocyte engraftment >0.5 x 10(9) per L and platelet engraftment >20 x 10(9) per L was 9 (8-11) and 10.5 (7-21) days, respectively. CONCLUSION: The cryopreservation of PBPC components at standard concentrations and 3.3 (1.8-6.2)-fold cell concentrations has no adverse effect on the function of HPCs after thawing.     

A cell-kinetic model of CD34+ cell mobilization and harvest: development of a predictive algorithm for CD34+ cell yield in PBPC collections

BACKGROUND: Mobilization and homing of PBPCs are still poorly understood. Thus, a sufficient algorithm for the prediction of PBPC yield in apheresis procedures does not yet exist. STUDY DESIGN AND METHODS: The decline of CD34+ cells in the peripheral blood during apheresis and their simultaneous increase in the collection bag were determined in a prospective study of 18 consecutive apheresis procedures. A cell-kinetic, four-compartment model describing these changes was developed. Retrospective data from 136 apheresis procedures served to further improve this model. A predictive algorithm for the yield was developed that considered the sex, weight, and height of the patient, the number of CD34+ cells in peripheral blood before apheresis, the inlet flow, and the duration of the apheresis. The accuracy of this algorithm was evaluated by comparison of the predicted and the observed yields of CD34+ cells in 105 prospective autologous and 148 retrospective allogeneic apheresis procedures. RESULTS: The correlation between predicted and observed yields was good for the autologous and allogeneic groups with a correlation coefficient (r) of 0.8979 and 0.8311 (p<0.0001), respectively. The regression is described by the equations log (measured value [m]) = 1.0118 + 0.8595 x log (predicted value [p]) for the autologous and log (m) = 2.226 + 0.7559 x log (p) for the allogeneic group. The respective equations for the zero-point regression are log (m) = 1.014 x log (p) and log (m) = 1.026 x log (p). The probability that the measured value was 90 percent or more of the predicted value was 83.8 percent for the autologous and 90.5 percent for the allogeneic apheresis procedures. CONCLUSION: The predictive accuracy of the algorithm and the slope of the zero-point regression curve were higher for allogeneic than autologous PBPC collections. The predictive algorithm may be a useful tool in PBPC harvest, enabling the adaptation of the size of the apheresis to the needs of each patient.     

Factors affecting mobilization of CD34+ cells in normal donors treated with filgrastim

BACKGROUND: Multiple days of apheresis are required for some normal peripheral blood progenitor cell (PBPC) donors, to ensure a sufficient collection of CD34+ cells for allografting. It would be of practical value to be able to identify the patients with poor mobilization on the basis of simple pretreatment clinical or hematologic variables. STUDY DESIGN AND METHODS: Clinical characteristics and laboratory data for 119 normal PBPC donors who underwent apheresis on Days 4 to 6 of treatment with granulocyte-colony-stimulating factor (filgrastim) were analyzed for correlations with CD34+ cell yield from the first day of apheresis. RESULTS: The CD34+ cell yield was significantly lower in donors who were more than 55 years of age, who underwent apheresis on Day 4 of filgrastim therapy, or who were not obese. There were weak direct correlations between CD34+ cell yield and the baseline white cell count, preapheresis white cell count, and preapheresis mononuclear cell count, and there was a weak inverse correlation with age. Twenty- one donors (18%) were considered to have poor mobilization (< 20 × 10(6) CD34+ cells/L blood processed). In the multivariate analysis, the only significant factor was age greater than 55 years, which conferred a 3.8 times greater risk (95% CI, 1.1-13.7) of poor mobilization (p = 0.04). However, poor mobilization occurred in all age groups, so the predictive value of the model was low. CONCLUSION: Donor variables correlated with CD34+ cell yield only weakly, so no particular clinical characteristic can be used to exclude an individual as a PBPC donor if he or she is otherwise suitable for the apheresis procedure.     

Serial granulocytapheresisunder daily administration of rHuG-CSF: effects on peripheral blood counts, collection efficiency, and yield

BACKGROUND: An option for treatment of severe infections in neutropenic patients is the transfusion of granulocytes from donors stimulated with rHuG-CSF. The schedule of rHuG-CSF-stimulated granulocyte donations and the quality of the components remain controversial. This study was done with the intention of ensuring daily granulocyte support with therapeutic cell numbers, while keeping the patients' allogeneic exposure as low as possible. STUDY DESIGN AND METHODS: Granulocyte collection with multiple consecutive leukapheresis procedures under daily rHuG-CSF administration and with hydroxyethyl starch as sedimenting agent were prospectively studied. Complete blood counts of the donors, collection yield, and efficiency were analyzed. RESULTS: Products (n = 259) from 76 donors were examined. The median peripheral blood WBC and neutrophil counts were 28.1 g per L and 24.1 g per L, respectively, and they were significantly higher on Day 5 of collections than on Days 1 to 3. Platelet counts and Hb levels decreased steadily. Collection yields increased over time from 4.9 to 6.7 x 10(10) neutrophils. Side effects of cytokines and aphereses did not exceed World Health Organization grade II status. CONCLUSION: Repetitive daily rHuG-CSF administration-even under daily leukapheresis procedures-results in a continuing increase in WBC and neutrophil levels and thus leads to increased collection yields. Side effects are tolerable, although Hb and platelet levels should be monitored closely.     

Inverse relationship between patient peripheral blood CD34+ cell counts and collection efficiency for CD34+ cells in two automated leukapheresis systems

BACKGROUND: The purpose of this study was to analyze the CD34 cell collection efficiency (CE) of automated leukapheresis protocols of two blood cell separators (Spectra, COBE [AutoPBSC protocol] and AS104, Fresenius [PBSC-Lym, protocol]) for peripheral blood progenitor cell (PBPC) harvest in patients with malignant diseases. STUDY DESIGN AND METHODS: PBPCs were collected by the Spectra AutoPBSC protocol in 95 patients (123 collections) and the AS104 PBSC-Lym protocol in 87 patients (115 harvests). Patients underwent a median of one (range, 1-4) conventional-volume apheresis procedure of 10.8 L (9.0-13.9) to obtain a target cell dose of > or =2.5 x 10(6) CD34+ cells per kg. RESULTS: The median overall CD34 CE was significantly better on the AS104 than on the Spectra: 55.8 percent versus 42.4 percent (p = 0.000). This was also true below (59.2% vs. 50.1%; p = 0.022) and above (51.2% vs. 41.3%; p = 0.001) the preleukapheresis threshold of 40 CD34+ cells per microL needed to collect a single-apheresis autograft. However, at > or =40 circulating CD34+ cells per microL, both cell separators achieved the target of > or =2.5 x 10(6) CD34+ cells per kg. The CD34 CE dropped significantly, from 59.2 percent at <40 cells per microL to 51.2 percent at > or =40 cells per microL on the AS104 (p = 0.017) and from 50.1 percent to 41.3 percent on the Spectra (p = 0.033). CONCLUSION: Whereas the CD34 CE was significantly different with the AS104 and the Spectra, the CD34 CE of both machines correlated inversely with peripheral blood CD34+ cell counts, showing a significant decline with increasing numbers of circulating CD34+ cells. Nevertheless, at > or 40 preapheresis CD34+ cells per microL, sufficient hematopoietic autografts of > or =2.5 x 10(6) CD34+ cells per kg were harvested by a single conventional-volume (11 L) leukapheresis on both cell separators.     

The dose of granulocyte–colony-stimulating factor after chemopriming treatment does not influence apheresis yield of progenitor cells: a retrospective study of 91 cases

BACKGROUND: The optimal dose of post-chemotherapy granulocyte–colony-stimulating factor (G–CSF) administration before peripheral blood progenitor cell (PBPC) collection has not been determined as yet, although 5 μg per kg per day has been recommended as the standard dose. This study retrospectively analyzed the effect of G–CSF dose on peripheral blood CD34+ cell collection from 91 patients with hematologic malignancies.
STUDY DESIGN AND METHODS: Various doses of G–CSF were administered after several chemotherapeutic PBPC mobilization regimens. According to the dose of G–CSF administered, patients were assigned to two groups. Group 1 included 46 patients who received a low dose of G–CSF (median, 3.6 [range, 2.8-4.6] μg/kg/day). Group 2 included 45 patients who received a standard G–CSF dose of 6.0 (5.5-8.1) μg per kg per day. Patients in the two groups were matched for age, diagnosis, previous therapy, and chemotherapeutic PBPC mobilization regimens.
RESULTS: No difference was observed in the median number of CD34+ cells harvested from each group. The number of leukapheresis procedures necessary to obtain a minimum of 3 × 10⁶ CD34+ cells per kg was the same in both groups, and the percentage of patients who failed to achieve adequate PBPC collections was similar in the two groups.
CONCLUSION: The administration of low-dose G–CSF after chemotherapy appears equivalent to administration of the standard dose in achieving satisfactory PBPC collection. This approach could allow significant savings in medical cost. A randomized and prospective study is necessary, however, to assess the validity of these conclusions.     

Cytokines and vascular cell adhesion molecule-1 in the blood of patients undergoing HPC mobilization

BACKGROUND: The mechanism of HPC mobilization in humans is unclear. In this study, the relationship between PBPC mobilization and blood levels of G-CSF, endogenous cytokines (IL-8, SCF, thrombopoietin [TPO]), and the vascular cell adhesion molecule-1 (VCAM-1) was analyzed in patients with malignancy who were undergoing a PBPC mobilization regimen. STUDY DESIGN AND METHODS: Fifty-four patients with multiple myeloma (MM) and 29 with breast cancer (BC) underwent a mobilization regimen combining conventional chemotherapy and G-CSF up to the last day of PBPC collection. The CD34+ cell count was determined on each day when leukapheresis was scheduled. Venous blood samples (n = 117) were drawn before apheresis for CD34+ cell count (flow cytometry) and cytokine (G-CSF, IL-8, SCF, TPO) and VCAM-1 measurements (ELISA). RESULTS: In multiple regression analysis, SCF was a significant determinant of CD34+ cell levels in BC patients (R = 0.50, p = 0.03) and of VCAM-1 levels in MM patients (R = 0.32, p = 0.02). SCF was negatively correlated with CD34+ cell count in patients with BC. SCF and VCAM-1 blood levels were correlated in MM and BC patients. CONCLUSION: SCF and VCAM-1 could play a role in PBPC mobilization in patients and could be useful measures by which to study patients undergoing a mobilization regimen.     

In vitro collection and posttransfusion engraftment characteristics of MNCs obtained by using a new separator for autologous PBPC transplantation

BACKGROUND: A clinical study was performed to evaluate the peripheral blood progenitor cell (PBPC) collection, transfusion, and engraftment characteristics associated with use of a blood cell separator (Amicus, Baxter Healthcare). STUDY DESIGN AND METHODS: Oncology patients (n = 31) scheduled for an autologous PBPC transplant following myeloablative therapy were studied. PBPCs were mobilized by a variety of chemotherapeutic regimens and the use of G-CSF. As no prior studies evaluated whether PBPCs collected on the Amicus separator would be viable after transfusion, to ensure patient safety, PBPCs were first collected on another cell separator (CS-3000 Plus, Baxter) and stored as backup. The day after the CS-3000 Plus collections were completed, PBPC collections intended for transfusion were performed using the Amicus instrument. For each transplant, >2.5 x 10(6) CD34+ PBPCs per kg of body weight were transfused. RESULTS: Clinical data collected on the donors immediately before and after PBPC collection with the Amicus device were comparable to donor data similarly obtained for the CS-3000 Plus collections. While the number of CD34+ cells and the RBC volume in the collected products were equivalent for the two devices, the platelet content of the Amicus collections was significantly lower than that of the CS-3000 Plus collections (4.35 x 10(10) platelets/bag vs. 6.61 x 10(10) platelets/bag, p<0.05). Collection efficiencies for CD34+ cells were 64 +/- 23 percent for the Amicus device and 43 +/- 14 percent for the CS-3000 Plus device (p<0.05). The mean time to engraftment for cells collected via the Amicus device was 8.7 +/- 0.7 days for >500 PMNs per microL and 9.7 +/- 1.5 days to attain a platelet count of >20,000 per microL-equivalent to data in the literature. No CS-3000 Plus backup cells were transfused and no serious adverse events attributable to the Amicus device were encountered. CONCLUSIONS: The mean Amicus CD34+ cell collection efficiency was better (p<0.05) than that of the CS-3000 Plus collection. Short-term engraftment was durable. The PBPCs collected with the Amicus separator are safe and effective for use for autologous transplant patients requiring PBPC rescue from high-dose myeloablative chemotherapy.     

Large-volume leukapheresis for peripheral blood progenitor cell collection in low body weight pediatric patients: a single center experience.

Peripheral blood progenitor cells (PBPC) have became the preferred source of stem cells for autologous transplantation because of easier accessibility, rapid engraftment, and lower tumor cell contamination. In pediatric patients is very important to optimize peripheral blood stem cells (PBSC) harvesting to obtain a sufficient number of cells with a reduced number of leukapheresis. In this study we prospectively analyzed data on 43 large volume leukapheresis (LVL) from 20 consecutive low body weight pediatric patients with various malignancies. Patients' mean body weight was 16.6 kg (range, 8.9-32.0 kg), and the median age was 4 years (range, 1-10 y ears). Instead of saline, it was used irradiated and leukoreduced red blood cell (RBC) units to prime the machine in 15 patients weighting 25 kg or less. The median number of LVL was 2 (range, 1-4) and a mean of 5.2 patient's blood volume was processed per session lasting 165 min (range, 118-239). The mean number of CD34+ cells, one day before leukapheresis was 49 mm(-3) (range, 9-219). The PBPC collection yielded 24.7 x 10(8) total nucleated cells/kg (range, 6.2-74.0), 10.7 x 10(6) kg(-1) CD34+ cells (range, 3.6-53.7); 49.8 x 10(4) CFU-GM/kg (range, 6.4-198.1), and 65.6 x 10(4) BFU-E/kg (range, 7.6-198.1). The platelet count decreased significantly after each procedure 39.8 +/- 9.1 x 10(9) mm(-3) (range, 18.000-76.000) (p < 0.001). In conclusion, our data show that LVL for collection of PBPC in low weight pediatric patients is a safe and efficient procedure, but it may expose the patient to the risk of thrombocytopenia.     

Non-cryopreserved peripheral blood progenitor cells collected by a single very large-volume leukapheresis: a simplified and effective procedure for support of high-dose chemotherapy

High-dose chemotherapy with autologous peripheral blood progenitor cell (PBPC) support has become a widely used treatment strategy. In order to simplify the procedure, a single very large-volume leukapheresis programme combined with short-term refrigerated storage of the PBPC was developed. Seventy-two patients suffering from various relatively chemosensitive malignancies received high-dose chemotherapy, consisting of agents with short in vivo half-lives and 24 to 48 hours later, the refrigerated PBPC were reinfused. A single very large-volume apheresis was sufficient to obtain at least 2 x 10(6)/kg CD34+ cells in 58 patients (81%), and 63% had at least 2.5 x 10(6) CD34+ cells/kg. Only two patients (3%) were transplanted with less than 1 x 10(6) CD34+ cells/kg. In three patients (4%) leukapheresis was repeated because of insufficient number of PBPC. The median CD34+ cell count was 3 x 10(6)/kg. A median of 38.5 L blood (range, 21 to 59) was processed, which accounted for a median of 9 x patient's total blood volume. Very large-volume leukapharesis was well tolerated with symptomatic hypocalcemia being the most common (18%) side-effect. The median time to neutrophils >1.5 x 10(9)/L, and to self-supporting platelet count >25 x 10(9)/L, was 10 and 12 days after reinfusion of PBPC graft, respectively. There were no treatment-related deaths. Our results indicate that this simplified approach of PBPC transplantation can be associated with prompt hematologic recovery in most patients and that it can be useful in settings where facilities are limited or for certain diseases where conditioning regimens with short half-life are appropriate. J. Clin. Apheresis, 15:236-241, 2000.