Comparison of intermittent- and continuous-flow cell separators for the collection of autologous peripheral blood progenitor cells in patients with hematologic malignancies

BACKGROUND: The transplantation of autologous peripheral blood progenitor cells (PBPCs) after high-dose chemotherapy is a valuable therapy for patients with hematologic and solid malignancies. Several methods are used for harvesting PBPCs. The efficiency of intermittent- and continuous-flow blood cell separators in collecting progenitor cells from the blood of patients undergoing myeloablative treatment for cancer was compared. STUDY DESIGN AND METHODS: PBPC components (n = 133) were obtained from 72 patients by leukapheresis with continuous-flow machines (Spectra, COBE; CS 3000 Plus, Baxter) and with an intermittent-flow machine (MCS 3P, Haemonetics). The data were analyzed retrospectively. Blood samples obtained from the patients before leukapheresis and samples of the leukapheresis components themselves were analyzed for their content of RBCs, WBCs, platelets, and CD34+ cells. RESULTS: The Spectra processed more than twice the blood volume in the shortest time (15 L in 178 min), whereas the Baxter CS 3000 Plus (10 L in 185 min) and the MCS 3P (4.8 L in 239 min) processed significantly smaller volumes in a longer time. The mean ACD consumption was 403 mL with the MCS 3P, 900 mL with the CS 3000 Plus, and 1000 mL with the Spectra. The product volumes were 50 mL (CS 3000 Plus), 69 mL (MCS 3P), and 166 mL (Spectra). In all groups, differences in the preapheresis hemograms were not significant, but the Spectra group had fewer CD34+ cells than the other groups. Despite this, the differences in the number of CD34+ cells in the leukapheresis components of all groups were without statistical significance. In the Spectra group, the collection of MNCs of 104 percent and CD34+ cells of 154 percent was significantly more efficient than that in the MCS 3P group (42.2% and 56%, respectively) or the CS 3000 Plus group (50.8% and 47.15%) as related to the patients' blood volume. CONCLUSION: PBPC collection can be performed successfully with continuous-flow and intermittent-flow blood cell separators. The Spectra had the best recovery of CD34+ cells within the shortest time. Leukapheresis with the MCS 3P is indicated if only a single venous access is available.     

Allogeneic blood progenitor cell collection in normal donors after mobilization with filgrastim: the M.D. Anderson Cancer Center experience

BACKGROUND: Information on the safety and efficacy of allogeneic peripheral blood progenitor cell (PBPC) collection in filgrastim-mobilized normal donors is still limited. STUDY DESIGN AND METHODS: The PBPC donor database from a 42-month period (12/94-5/98) was reviewed for apheresis and clinical data related to PBPC donation. Normal PBPC donors received filgrastim (6 microg/kg subcutaneously every 12 hours) for 3 to 4 days and subsequently underwent daily leukapheresis. The target collection was > or =4 x 10(6)CD34+ cells per kg of recipient's body weight. RESULTS: A total of 350 donors were found to be evaluable. Their median age was 41 years (range, 4-79). Their median preapheresis white cell count was 42.8 x 10(9) per L (range, 18.3-91.6). Of these donors, 17 (5%) had inadequate peripheral venous access. Leukapheresis could not be completed because of apheresis-related adverse events in 2 donors (0.5%). Of the 324 donors evaluable for apheresis yield data, 221 (68%) reached the collection target with one leukapheresis. The median CD34+ cell dose collected (first leukapheresis) was 462 x 10(6) (range, 29-1463).The main adverse events related to filgrastim administration in donors evaluable for toxicity (n = 341) were bone pain (84%), headache (54%), fatigue (31%), and nausea (13%). These events were rated as moderate to severe (grade 2-3) by 171 (50%) of the donors. In 2 donors (0.5%), they prompted the discontinuation of filgrastim administration. CONCLUSION: PBPC apheresis for allogeneic transplantation is safe and well tolerated. It allows the collection of an "acceptable" PBPC dose in most normal donors with one leukapheresis, with minimal need for invasive procedures.     

Passenger lymphocyte syndrome with severe hemolytic anemia due to an anti-Jk(a) after allogeneic PBPC transplantation

BACKGROUND: After allogeneic peripheral blood progenitor cell (PBPC) transplantation, a patient developed a severe hemolytic transfusion reaction due to passenger lymphocyte syndrome. CASE REPORT: A 50-year-old woman with secondary acute myeloid leukemia transforming from a myelodysplastic syndrome received an ABO-compatible PBPC graft from her HLA-identical sister. For prophylaxis of GVHD, the patient was treated with cyclosporine and methotrexate. Eighteen days after the transplant, the patient experienced a severe hemolytic transfusion reaction due to an alloantibody (anti-Jk(a)) produced by donor lymphocytes. RESULTS: The patient was typed as group A, Jk(a+) before transplantation; the donor was typed as group A, Jk(a-). On Day 18 after transplantation, the immunohematologic screening revealed a positive DAT (C3d 3+) and an alloanti-Jk(a). Hemolysis in the patient at that time was indicated by a drop in the Hb and an increase in the LDH level (maximum, 592 IU/L on Day 23). CONCLUSION: The course of hemolysis and the time of appearance of an alloantibody in this patient meet the criteria for passenger lymphocyte syndrome. In most cases, this syndrome is triggered by ABO system antibodies. This is the first reported case of passenger lymphocyte syndrome after PBPC transplantation that was due to an alloantibody that did not belong to the ABO system.     

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.     

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.     

Ex vivo evaluation of PBMNCs collected with a new cell separator

BACKGROUND: This study reports on an evaluation of the ability of a cell separator (Amicus, Baxter Healthcare) and the integral MNC computer software program to collect a variety of MNC subsets. The collection efficiency (CE) of the Amicus for these MNC subsets was compared to that of another cell separator (CS-3000 Plus, Baxter). The collected MNCs were also assayed ex vivo to determine if these cells remained functional. STUDY DESIGN AND METHODS: Healthy volunteer blood donors were recruited to provide PBMNCs for the isolation of CD3+, CD4+, CD8+, CD19+, NK, and gammadelta+ cells and monocytes. Cells were collected with an Amicus (test arm; n = 16) or a CS-3000 Plus (control arm; n = 11) cell separator. Cells were counted on a flow cytometer and CEs were calculated. For functional studies, the Amicus-collected MNC data were compared to CS-3000 Plus historical data. Functional studies performed included surface antigen expression assays (CD8+), proliferation assays (CD4+ and CD8+ cells), NK cytotoxicity assays for K562 and HUVE cells, and E-selectin induction on endothelial cells through NK+ contact dependency. Dendritic cells (DCs) were generated from CD34+ cells collected on the Amicus, positively selected by the use of antibody-bound, magnetic bead technology, and then cultured ex vivo with a combination of growth factors to generate the DCs. RESULTS: CEs were higher on the Amicus than on the CS-3000 Plus for CD3+ (68 vs. 54%), CD4+ (70 vs. 56%), CD8+ (68 vs. 52%), and CD19+ (60 vs. 48%) cells (p<0.05). For the two separators, CEs were equivalent for monocytes, NK+, and gammadelta+ cells. The Amicus separator collected significantly fewer platelets than did the CS-3000 Plus (p<0.00001). CD4+, CD8+, and NK cells proliferated normally. NK cells appropriately stimulated E-selectin expression on endothelial cells. Culture-generated DCs obtained by using Amicus-collected CD34+ cells expressed appropriate cell surface markers. CONCLUSION: The Amicus separator is acceptable for the collection of PBMNC subsets. The device collects CD3+, CD4+, CD8+, and CD19+ T- and B-cell subsets with greater efficiency and collects MNCs with significantly fewer contaminating platelets than does the CS-3000 Plus. Cells collected on the Amicus are suitable for use in a variety of research and clinical immunobiologic studies.     

Assessment of rapid remobilization intervals with G–CSF and SCF in murine and rhesus macaque models

BACKGROUND: Defining the optimum regimen and time for repeat peripheral blood progenitor cell mobilization would have important clinical applications. STUDY DESIGN AND METHODS: Remobilization with SCF and G-CSF at 2 weeks after an initial mobilization in mice and at 2 or 4 weeks after an initial mobilization in nonhuman primates was examined. In mice, competitive repopulation assays were used to measure long-term progenitor cell-repopulating activity. In monkeys, mobilization of hematopoietic progenitor CFUs was used as a surrogate marker for progenitor cell-repopulating ability. RESULTS: Efficacy of progenitor cell remobilization differed in the two animal species. In mice, peripheral blood progenitor cell-repopulating ability with repeat mobilization at 2 weeks was 70 percent of that with the initial mobilization. In monkeys, there was no significant difference in peripheral blood progenitor cell mobilization between the initial and the repeat mobilizations at 2 weeks. In mobilizations separated by 4 weeks, however, peripheral blood progenitor cell mobilization was higher than that with initial mobilizations. CONCLUSION: In animal models, mobilization of peripheral blood progenitor cells with remobilization after a 2-week interval is similar to or moderately decreased from that with the initial mobilization. Progenitor cell collection at this time point may be useful in certain clinical circumstances. A 4-week interval between remobilizations may be preferable. Clinical trials in humans would be useful to clarify these issues.     

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.     

Delayed massive immune hemolysis mediated by minor ABO incompatibility after allogeneic peripheral blood progenitor cell transplantation

BACKGROUND: Bone marrow transplantation with minor ABO incompatibility may be followed by moderate delayed hemolysis of the recipient's red cells by donor-derived ABO antibodies. This reaction may be more severe after transplantation of peripheral blood progenitor cells (PBPCs). CASE REPORT: A 16-year-old boy underwent an allogeneic PBPC transplant from his HLA-mismatched mother as treatment for acute myeloblastic leukemia that had proved resistant to induction chemotherapy. Transfusion of the unmanipulated PBPCs proceeded without any complication, despite the difference in ABO blood group (donor, O Rh-positive; recipient, A Rh-positive). On Day 7, a rapid drop in hemoglobin to 4 g per dL was observed, which was attributed to a massive hemolysis. All the recipient's group A red cells were destroyed within 36 hours. This delayed and rapidly progressive hemolytic anemia was not associated with the transfusion of the donor's plasma. Rather, the anti-A titer increased in parallel with marrow recovery, which suggested an active synthesis of these antibodies by immunocompetent cells from the donor against the recipient's red cells. The mother's anti-A titer was retrospectively found to be 2048. Her unusually high titer is probably due to prior sensitization during pregnancies. On Day 12, the patient developed grade IV graft-versus-host disease, which proved resistant to all treatments instituted and led to his death on Day 35. CONCLUSION: PBPC transplantation with minor ABO incompatibility may be associated with significant risk of massive delayed hemolysis.     

Peripheral blood progenitor cell collection after epirubicin, paclitaxel, and cisplatin combination chemotherapy using EPO-based cytokine regimens: a randomized comparison of G-CSF and sequential GM-/G-CSF

BACKGROUND: The peripheral blood progenitor cell (PBPC) mobilization capacity of EPO in association with either G-CSF or sequential GM-CSF/G-CSF was compared in a randomized fashion after epirubicin, paclitaxel, and cisplatin (ETP) chemotherapy. STUDY DESIGN AND METHODS: Forty patients with stage IIIB, IIIC, or IV ovarian carcinoma were enrolled in this randomized comparison of mobilizing capacity and myelopoietic effects of G-CSF + EPO and GM-/G-CSF + EPO following the first ETP chemotherapy treatment. After ETP chemotherapy (Day 1), 20 patients received G-CSF 5 microg per kg per day from Day 2 to Day 13 and 20 patients received GM-CSF 5 microg per kg per day from Day 2 to Day 6 followed by G-CSF 5 microg per kg per day from Day 7 to Day 13. EPO (150 IU per kg) was given every other day from Day 2 to Day 13 to all patients in both arms of the study. Apheresis (two blood volumes) was performed during hematologic recovery. RESULTS: The magnitude of CD34+ cell mobilization and the abrogation of patients' myelosuppression were comparable in both study arms; however, GM-/G-CSF + EPO patients had significantly higher CD34+ yields because of a higher CD34+ cell collection efficiency (57.5% for GM-/G-CSF + EPO and 46.3% for G-CSF + EPO patients; p = 0.0009). Identical doses of PBPCs mobilized by GM-/G-CSF + EPO and G-CSF + EPO drove comparable hematopoietic recovery after reinfusion in patients treated with identical high-dose chemotherapy. CONCLUSION: The sequential administration of GM-CSF and G-CSF in combination with EPO is feasible and improves the PBPC collection efficiency after platinum-based intensive polychemotherapy, associating high PBPC mobilization to high collection efficiency during apheresis.     

Administration of G--CSF plus dexamethasone produces greater granulocyte concentrate yields while causing no more donor toxicity than G--CSF alone

BACKGROUND: G-CSF with or without dexamethasone is becoming the standard agent for mobilizing granulocytes for transfusion. The purpose of this study was to determine if the toxicities of G--CSF with or without dexamethasone are offset by greater collection yields and to define the minimum interval that should separate sequential collections. STUDY DESIGN AND METHODS: Twenty donors were studied on three occasions. They were given either dexamethasone (8 mg, by mouth) plus a placebo injection, G--CSF (5 microg/kg, given subcutaneously) plus placebo capsules, or G--CSF plus dexamethasone. Granulocytes were collected by apheresis. A donor symptom survey was administered, and cell counts and blood chemistries were assessed before collection and 1, 2, 7, 14, 21, 28, and 35 days after collection. RESULTS: More granulocytes were collected when G--CSF was given than when dexamethasone was given (41.1 +/- 20.4 x 10(9) vs. 21.0 +/- 10.0 x 10(9); p<0.001), but the use of G--CSF plus dexamethasone produced the greatest yields (67.1 +/- 22.0 x 10(9); p<0.002). When the donors were given dexamethasone alone, 58 percent experienced at least one symptom, compared to 85 percent of those given G--CSF and 75 percent of those given G--CSF plus dexamethasone. In all three regimens, platelet counts fell 19 percent to 24 percent after collection and remained below baseline for 7 to 14 days. Granulocyte counts returned to baseline within 3 to 7 days, but, in all three regimens, a mild granulocytopenia occurred 21 days after collection. With each of the regimens, blood chemistries changed, but the changes were mild and most returned to baseline within 7 days; however, changes in albumin, bilirubin, and AST persisted until 28 days after collection. CONCLUSION: These results support the use of G--CSF plus dexamethasone in granulocyte donors. G--CSF plus dexamethasone resulted in greater granulocyte yields than either agent alone and was associated with donor symptoms and changes in blood cell counts and chemistries similar to those seen with G--CSF alone or dexamethasone alone. Granulocytes can be safely collected a second time after a 7-day interval; however, for regular donors, it may be best to separate collections by 4 weeks.     

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.     

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.     

IL-10 increases the number of CFU-GM generated by ex vivo expansion of unmanipulated human MNCs and selected CD34+ cells

BACKGROUND: Ex vivo expansion strategies with different cytokine combinations are currently used by several groups as a means of increasing the number of HPCs for a variety of special clinical applications. Because there is little information on the potential role of IL-10 in such ex vivo expansion models, the effect of this cytokine on the generation of myeloid progenitor cells in suspension cultures was investigated. STUDY DESIGN AND METHODS: On the basis of data from the literature and from new experiments, the combination of SCF and IL-3 at concentrations of 100 ng per mL and 100 U per mL, respectively, was chosen as the standard cocktail. The addition of IL-10 to such cultures resulted in a marked and dose-dependent potentiation of myeloid progenitor cell production. RESULTS: Using unmanipulated leukapheresis components from 13 individuals (including lymphoma and cancer patients and normal donors), the expansion multiple of CFU-GM after 14 days as compared with pre-expansion values was 9.54 +/- 2.31 times by SCF/IL-3 and 46.38 +/- 7.37 times by the combination of SCF/IL-3 and 100 ng per mL of IL-10 (p<0.001). IL-10 also potentiated CFU-GM generation from selected CD34 PBMNCs (n = 9) with an expansion of 17.22 +/- 7.04 times versus 45.67 +/- 16.78 times using the SCF/IL-3 and SCF/IL-3/IL-10 combination, respectively (p<0.05). Moreover, expansion-promoting effects of IL-10 were observed in liquid cultures containing MNCs from bone marrow (n = 4) and cord blood (n = 3), but did not reach statistical significance because of the small number of samples. CONCLUSION: These results suggest IL-10 as a useful cytokine to optimize progenitor cell-expansion strategies for clinical application.     

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.     

Improved progenitor assay standardization using peripheral blood progenitor cells from a donor treated with granulocyte–colony-stimulating factor

BACKGROUND: Progenitor assays are the principal method for evaluating hematopoietic cell function. The magnitude of assay variability and the assay steps contributing to variability were determined, and modifications intended to increase assay consistency were evaluated. STUDY DESIGN AND METHODS: Assays were performed using a serum-free progenitor assay medium with cells plated at 5.0 x 10(4) and 1.0 x 10(5) cells per plate. A peripheral blood progenitor cell component collected from a normal donor after administration of granulocyte-colony-stimulating factor was divided into identical aliquots. Each experiment involved at least 5 technologists, each performing assays in duplicate on five aliquots, with each person scoring all assay plates. Three sample preparation methods were tested: 1) ficoll mononuclear cell enrichment and sample dilution, 2) sample dilution without ficoll separation, and 3) sample dilution without ficoll separation, with cell counts performed before and after each dilution step, dilution volumes calculated on the basis of each cell count, automated electronic pipettors used in dilution steps, and colony frequency calculated on the basis of cell counts from the final specimen. RESULTS: Global variability for colony-forming units-granulocyte-macrophage, represented by the percentage of CV for all specimens and all technologists, was 89.6 percent at 5.0 x 10(4) cells per plate and 81.3 percent at 1.0 x 10(5), when ficoll separation was used. Subjective differences in scoring plates did not account for most of the variability observed, as results for any individual plate read by multiple technologists had a mean CV of 15.6 percent and 19.7 percent at the two plating concentrations. Method 3 resulted in the greatest improvement, reducing CV to 24.4 percent at 5.0 x 10(4) cells per plate and to 24.2 percent at 1.0 x 10(5) cells per plate. Similar results were obtained for erythroid-burst-forming units. CONCLUSIONS: Baseline assay results were extremely inconsistent. Interindividual differences in colony interpretation did not contribute significantly to assay variability, although sample preparation and plating did. Improved control over cell concentration decreased assay variability by 70 to 73 percent.     

Effects of different concentrations of anticoagulant on the in vitro characteristics of autologous whole blood

BACKGROUND: Routinely, 450 mL of blood is collected into 63 mL of CPDA-1, for a final anticoagulant:blood ratio of approximately 1:7 in a whole-blood autologous unit. If less than 300 mL of blood is to be collected, the AABB standards suggest that there should be a proportionate decrease in anticoagulant. Data from an autologous blood program showed a range in volume from 92 mL to 667 mL per bag, which reflects an anticoagulant:blood ratio of 2:1 to 1:10. STUDY DESIGN AND METHODS: To determine the effects of these ratios on the in vitro function of RBCs at various anticoagulant ratios, blood was collected into different amounts of anticoagulant, and various measurements were made during storage. RESULTS: The number of RBCs and the MCV remained constant over time, regardless of the anticoagulant dilution used. Plasma free Hb increased with time with all dilutions. At a 1:2 ratio, it rose from 734 mg per L on Day 1 to 1805 mg per L on Day 35, and at 1:8, it was 355 mg per L for Day 1 and 854 mg per L on Day 35. Plasma sodium decreased and the potassium increased over time with all dilutions. From Day 1 to Day 35, there was a nine-fold increase in potassium at both the 1:2 and 1:8 dilutions (2.4 to 22.9 mmol/L, 3.2 to 29.6 mmol/L, respectively). The LDH increased over time and the pH decreased in all of the dilutions. Osmotic fragility remained constant at the 1:8 dilution but decreased at all of the other dilutions with storage, with 44-percent fragility on Day 35 at the 1:2 ratio. The WBC and platelet counts decreased consistently over time. Overall, 1 percent of the autologous units were below the cutoff volume of 300 mL at which an adjustment of the anticoagulant volume is required. CONCLUSION: Plasma Hb and plasma potassium concentrations are considerably higher in low-volume units, which indicates that deviation from standard collection procedures is deleterious to RBCs.