High-dose etoposide was incorporated into a regimen of fractionated total-body irradiation (FTBI) and high-dose cyclophosphamide before autologous transplant with the goal to enhance the antitumor effect of the myeloablative regimen in poor-risk lymphoid malignancies.

Peripheral blood stem cell (PBSC) transplantation (PBSCT) following high-dose chemotherapy is considered to be an effective and curative strategy for patients with certain malignancies. Optimal conditions for collection of PBSC and successful PBSCT, however, are still controversial. We performed 57 leukaphereses after 19 courses of chemotherapy for mobilization of PBSC (semi-high-dose VP-16 alone; 500 mg/m2/day for 3 or 4 days, 13 courses, or conventional chemotherapy; six courses) combined with subsequent G-CSF administration in 13 patients with malignancies (six with lymphoma, five with leukemia, and two with germ cell tumors). Total numbers of the CD34+ cells and CFU-GM obtained by multiple leukaphereses after one course of mobilization therapy were 0.63-168.74 x 10(6)/kg (mean 33.94) and 0.15-56.0 x 10(5)/kg (mean 8.22), respectively. We demonstrated that many cellular components of peripheral blood (PB) on the day of PBSC harvest, especially CD34+ cell, total leukocyte, myelocyte and monocyte counts, were correlated with the numbers of CFU-GM obtained in each leukapheresis. A daily increase of leukocyte counts was another useful indicator for the day of PBSC harvest. We also found that the time when total leukocyte counts in PB recovered to more than 5000/microliters or when CD34+ cells within PB mononuclear cells exceeded 1% was optimal for PBSC harvest. Our results confirmed that the semi-high-dose regimen with VP-16 combined with G-CSF is a safe method which has both antitumor effects and mobilization ability of PBSC in patients with hematological malignancies. PBSCT following various high-dose chemotherapy regimens with or without total body irradiation was also performed in 11 of the 13 patients, and rapid hematologic recovery was observed in all of the patients.

We carried out a pilot study to evaluate the combined use of recombinant human erythropoietin (rhEpo) and granulocyte colony-stimulating factor (G-CSF) for accelerating marrow engraftment in children given allogeneic bone marrow transplantation (BMT). Fifteen consecutive children were enrolled in this study; 13 completed it and were evaluable. Using analysis of variance, laboratory and clinical data referring to these children were compared with those of 15 patients previously treated with rhEpo alone and with those of 16 historical controls. Erythroid repopulation, evaluated sequentially through serum transferrin receptor and reticulocyte count, was similarly accelerated in children receiving rhEpo alone and in those receiving combined treatment. These latter, however, showed a further reduction in the total number of red blood cell units required to reach transfusion independence (1.1 +/- 0.7 in the study population vs 2.7 +/- 1.2 in rhEpo group vs 4.2 +/- 2.3 in historical controls; values are mean +/- 1 SD; p < 0.001). Neutrophil engraftment, i.e. time for neutrophils to reach 0.5 x 10(9)/l, was 11 +/- 3 days in children receiving combined treatment, significantly shorter than that of the control groups (16 +/- 3 and 18 +/- 5, respectively; p < 0.001). Acceleration of neutrophil recovery translated into fewer infections: days of fever were significantly reduced in the study population (4 +/- 2 vs 11 +/- 8 vs 15 +/- 6, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Primed peripheral blood progenitor cells (PBPC) with hematopoietic growth factors enhance marrow engraftment after autologous bone marrow transplantation (BMT). G-CSF and GM-CSF stimulate the production of PBPC; both cytokines alone also stimulate neutrophil recovery after autologous BMT. Little data exist comparing these two cytokines. We prospectively studied G-CSF and GM-CSF in autologous BMT. Forty-four consecutive patients with either Hodgkin's disease or non-Hodgkin's lymphoma underwent autologous BMT using both PBPC and autologous marrow. The autologous BMT preparative regimen was CBV (VP-16 2400 mg/m2, CY 1800 mg/m2 i.v. four times daily for 4 days, BCNU 600 mg/m2). Sixteen patients received G-CSF 5 micrograms/kg sc daily for 8 days for mobilization of PBPC and received G-CSF 16 micrograms/kg i.v. four times daily after autologous BMT. Twenty-eight patients received GM-CSF to mobilize PBPC (14 patients received 250 micrograms/m2 sc daily for 8 days; 14 patients received 125 micrograms/m2 sc twice daily for 8 days) and GM-CSF (250 micrograms/m2 i.v. four times daily) after autologous BMT. Patients underwent three to five pheresis procedures to harvest at least 3 x 10(8) nucleated cells/kg. Patients receiving G-CSF had higher peripheral WBC counts than did those receiving GM-CSF. Total numbers of mononuclear cells, total CD34+ cells and total CD34+/33-negative cells were similar in the two treatment groups. The patients receiving G-CSF after autologous BMT experienced a more rapid engraftment of both neutrophils (9 days vs 13 days, p = 0.0001) and platelets (14 days vs 18 days, p = 0.027) than did patients receiving GM-CSF after transplant.(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid hematopoietic reconstitution following peripheral blood progenitor cell (PBPC) autotransplantation is thought to result from reinfusion of committed progenitor cells. This has raised concern that PBPC autografts might be rich in committed hematopoietic progentors responsible for early engraftment, but deficient in more primitive progenitors required for long-term hematopoietic reconstitution. The granulomonocytic colony-forming unit (CFU-GM) assay measures committed progenitors responsive to a single species of colony-stimulating activity such as granulocyte-macrophage colony-stimulating factor (GM-CSF), whereas the pre-CFU assay identifies more primitive progenitors by measuring interleukin-3 (IL-3) and kit ligand (KL) induced generation of secondary CFU-GM from CD34+, 4-hydroperoxycyclophosphamide resistant progenitors that require multiple cytokine stimuli. Paired bone marrow (BM) and PBPC samples from 17 breast and ovarian cancer patients participating in four separate clinical trials were compared in these assay systems. In seven of nine patients, PBPC autografts mobilized with cyclophosphamide rebound and G-CSF compared favorably with paired BM autografts in both committed and primitive progenitor capacity. Failure to mobilize substantial primitive progenitor cell numbers occurred in two of nine patients undergoing this mobilization regimen and could not have been predicted by either circulating CFU-GM or CD34+ cell number. Prior myelosuppressive treatment experiences reduced peripheral progenitor yields somewhat, but still allowed for the collection of PBPC autografts which compared favorably with BM autografts in total CFU-GM and Pre-CFU. Mobilization of PBPC with G-CSF or GM-CSF alone in patients who had received prior myelosuppressive therapies produced autografts which were relatively deficient in committed progenitors, but absolutely deficient in primitive progenitors. We conclude that optimization of patient characteristics and mobilization parameters can achieve PBPC autografts rich in both the primitive and committed hematopoietic progenitor cells.

With the aim of facilitating the ex vivo manipulation of peripheral blood hematopoietic progenitors (CPCs = circulating progenitor cells) collected by leukapheresis, we removed polymorphonuclear cells and monocytes that naturally adhere to nylon wool fibers. Leukapheresed cells harvested at the time of hematopoietic recovery after cancer therapy with high-dose cyclophosphamide plus hematopoietic growth factors were incubated with nylon wool fibers for 1 h at 37 degrees C. Evaluation of the cells non-adherent to the nylon wool in all experiments (n = 14) showed that the median recovery of nucleated cells and CPCs detected as CD34+ cells, CFU-GM and BFU-E was 16.4% (range 4.8%-34.0%), 60.0% (range 30.8-80.8%), 60.9% (range 33.4-74.5%) and 65.5% (range 30.8-69.2%), respectively. Therefore exposure to the nylon wool determined a selective removal of mature cells and a complementary enrichment of CPCs. The wide range of results depended on the significantly different cell compositions of the unmanipulated leukaphereses. The latter from patients receiving rhG-CSF (n = 10) comprised a median of 88.5% (range 77.8-93.8%) and 11.5% (range 6.2-22.2%) polymorphonuclear and mononuclear cells, respectively. In contrast, leukaphereses from patients receiving rhGM-CSF or PIXY321 (n = 4) comprised a median of 71.1% (range 55.4-85.0%) and 28.9% (range 15.0-44.6%) polymorphonuclear and mononuclear cells, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Our purpose was to determine the maximum tolerated dose of, and the minimum interval between treatments with, multiple cycles of carboplatin (CBDCA) rescued with peripheral blood progenitors and filgrastim. Eligible patients had advanced cancers without prior chemotherapy or radiotherapy. The study design involved a sequential cross-over in which patients initially received two or three courses of cyclophosphamide (CPA) at a dose of 3.0 g/m2, supported by filgrastim. Multiple leukaphereses were then performed during the rebound phase of hematological recovery following each CPA-induced nadir to harvest peripheral blood progenitors, which were then reinfused as rescue following each of four courses of CBDCA. We attempted to administer the CBDCA at 14-day intervals. The CBDCA dose (mg/m2/course) was escalated as follows in successive cohorts of patients: Level I, 500; Level II, 800; Level III, 1200; Level IIIa, 1000. Following determination of the maximum tolerated dose of CBDCA administered in this fashion, a subsequent cohort of patients (Level IV) were treated with two courses of high-dose CPA and four courses of the combination of CBDCA (1000 mg/m2) plus CPA (1500 mg/m2). Thirty-one patients were enrolled in the trial. Five patients were removed from study prior to completion of protocol therapy, three due to toxicity and two who developed progressive cancer while on study. The maximum tolerated dose of CBDCA was 1000 mg/m2, with dose-limiting ototoxicity occurring at 1200 mg/m2. The median inter-treatment interval for all cycles was 15 days (range, 12-30). The median intervals between CBDCA courses for each dose level were: Level I, 17 days; Level II, 17 days; Level III, 14 days; Level IIIa, 15 days; Level IV, 16 days. The median dose intensity of the CPA phase was 1493 mg/m2/week. The median (and range) CBDCA dose intensities (measured from the start of CBDCA) for each dose level were: I, 185 (151-222); II, 328 (305-380); III, 567 (512-646); IIIa, 465 (363-481); Level IV, 468 (333-500). Neutropenic fever complicated 35 of 113 CBDCA or CBDCA/CPA courses. Platelet transfusion was required in 51 of 113 courses. One patient had severe epistaxis. There were no treatment-related deaths. Among 27 patients with ovarian cancer who were evaluable for response, there were 5 pathologically documented complete (including 3 of 10 at Level IV) and 16 partial responses. We concluded that peripheral blood progenitors facilitate the simultaneous dose escalation and schedule intensification of carboplatin chemotherapy. The effect is sustained over four courses of treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Patients who undergo transplantation with haploidentical "three-loci" mismatched T-cell-depleted bone marrow (BM) are at high risk for graft failure. To overcome the host-versus-graft barrier, we increased the size of the graft inoculum, which has been shown to be a major factor in controlling both immune rejection and stem cell competition in murine models. Seventeen patients (mean age, 23.2 years; range, 6 to 51 years) with end-stage chemoresistant leukemia were received transplants of a combination of BM with recombinant human granulocyte colony-stimulating factor-mobilized peripheral blood progenitor cells from HLA-haploidentical "three-loci" incompatible family members. The average concentration of colony-forming unit-granulocyte-macrophage in the final inoculum was sevenfold to 10-fold greater than that found in BM alone. The sole graft-versus-host disease (GVHD) prophylaxis consisted of T-cell depletion of the graft by the soybean agglutination and E-rosetting technique. The conditioning regimen included total body irradiation in a single fraction at a fast dose rate, antithymocyte globulin, cyclophosphamide and thiotepa to provide both immunosuppression and myeloablation. One patient rejected the graft and the other 16 had early and sustained full donor-type engraftment. One patient who received a much greater quantity of T lymphocytes than any other patient died from grade IV acute GVHD. There were no other cases of GVHD > or = grade II. Nine patients died from transplant-related toxicity, 2 relapsed, and 6 patients are alive and event-free at a median follow-up of 230 days (range, 100 to 485 days). Our results show that a highly immunosuppressive and myeloablative conditioning followed by transplantation of a large number of stem cells depleted of T lymphocytes by soybean agglutination and E-rosetting technique has made transplantation of three HLA-antigen disparate grafts possible, with only rare cases of GVHD.

Patients with advanced adenocarcinoma of the colon, rectum or pancreas were entered into trials for evaluation of treatment with sequential doses of IL-3 and GM-CSF. They received 0.25 to 5 micrograms IL-3/kg/d for up to 7 days, followed by 1 microgram GM-CSF/kg/day for a maximum of 10 further days. We assessed the kinetics of bone-marrow cell proliferation and of blood production using tritiated thymidine labelling in vitro and in vivo. Megakaryocytic-CFC were unaffected but proliferation rates of GM-CFC and BFU-E were increased. Progenitor cells were mobilized (12-fold over baseline) into the peripheral blood. The proliferative activity of maturing cells in the marrow was increased (cell-cycle times were reduced by at least 30%). This translated into amplified blood cell production (WCC approximately 30 x 10(9)/l), a 2.2-fold increase in platelet counts and significant eosinophilia. Newly generated neutrophils appeared in the circulation at the normal time and their peripheral half-life was also normal. The calculated 3.2-fold amplification in neutrophil production required nearly 2 extra divisions in the marrow, shared between the progenitors and the proliferating granulocytic cells. The results were compared with those of a previous trial using GM-CSF only, although at a 10-fold higher dose level. Comparable levels of peripheral neutrophils were obtained in both trials but significant ineffective granulopoiesis developed in the earlier study. This was overcome in the present study, the priming dose of IL-3 apparently giving the latitude to utilize lower doses of GM-CSF with less risk of complications.

Mononuclear cell preparations from peripheral blood after mobilization with hematopoietic growth factors have been shown to induce accelerated neutrophil and platelet recovery as compared with that induced by autologous bone marrow transplantation after myeloablative chemotherapy. Because these mononuclear cell products contain many immunocompetent cells other than hematopoietic progenitors, these accessory cells might contribute to the rapid immunohematopoietic reconstitution. We have monitored the concentrations of soluble CD4 (sCD4), sCD8, and sCD25; the recovery of the lymphocyte subsets and of natural killer (NK) cells; and the endogenous levels of granulocyte colony-stimulating factor (G-CSF), interleukin-3 (IL-3), IL-6, and granulocyte-macrophage-CSF (GM-CSF) in 12 patients who underwent high-dose chemotherapy supported by blood stem cells that were obtained by mobilization with chemotherapy and GM-CSF. The concentrations of both G-CSF and IL-6 peaked at 7 days after reinfusion of stem cells, and this transient elevation preceded the increase in the white blood cell count by approximately 5 to 7 days. The levels of sCD4 and sCD8 increased to a maximum on day 21, and the time to peak levels coincided with the maximum increase in white blood cell count, absolute neutrophil count, or lymphocytes. The levels of sCD25 were found to be elevated from day 7 to day 21. Statistically, the increases in sCD4, sCD8, sCD25, G-CSF, and IL-6 were highly significant, whereas there were no significant changes in IL-3 and GM-CSF. A rapid recovery of the NK activity was found in all 8 of the patients who could be monitored for this assay. Therefore, our study suggests that recovery of CD4+ cells, CD8+ cells, and NK activity coincided with that of neutrophils, which is preceded by a marked, but transient, elevation of IL-6 and G-CSF.

Autologous stem cell transplantation has become an important therapy in multiple myeloma (MM). To develop adequate autograft purging methods, it is necessary to determine whether antigens expressed on early hematopoietic progenitors exist on malignant cells. The Ig heavy chain produced by the MM cells shows evidence of prior somatic mutation without intraclonal diversity. As a result, this sequence can be used as a specific marker to detect all members of the malignant clone. The Ig heavy chain sequence expressed by the MM cells was obtained in five patients with advanced disease. Patient specific oligonucleotide primers were designed based on the complementarity determining regions (CDR) of each MM Ig sequence and used to amplify DNA by polymerase chain reaction for the detection of malignant cells. A highly purified collection of CD34+ cells was obtained after passage of the initial bone marrow cells through an immunoadsorption column and fluorescence-activated cell sorting. Despite an assay sensitivity of 1 tumor cell in 2,500 to 44,000 normal cells, none of the CD34+ samples showed product with the myeloma-specific CDR primers. Therefore, positive selection for cells bearing this antigen should yield a tumor-free autograft capable of providing hematopoietic recovery after myeloablative chemotherapy.

An examination of the in vitro sensitivity of marrow burst-forming units for erythroid (BFU-E) to various concentrations of human recombinant erythropoietin (rEpo) and interleukin-3 (IL-3, 20 ng/mL) in serum-deprived methylcellulose cultures revealed that cells obtained from patients with chronic renal failure showed a defective response to rEpo, particularly at lower concentrations. This poor response was not corrected by the addition of neutralizing antibodies to antitumor necrosis factor-alpha or antiinterleukin-1 alpha/beta. When purified CD34+ cells from these patients were tested for dose-dependent growth to rEpo, the curve resembled that of normal donors, indicating that there was an intrinsic defect in the patients' progenitor/accessory cell interactions. Using unseparated cells from the patients, we then tested whether the interaction between erythroid differentiation factor (EDF) and rEpo affected BFU-E growth. Although EDF, either alone or in combination with IL-3, did not affect the growth of BFU-E in the absence of rEpo, the reduced sensitivity to rEpo in the patients was brought closer to normal limits by the addition of 10 ng/mL EDF to the cultures. The present results may suggest the possibility that, in patients with renal anemia, concomitant administration of EDF may increase the therapeutic ratio of rEpo therapy by enhancing the sensitivity of progenitor cells to rEpo, thereby decreasing the therapeutic dose of costly rEpo.

The purpose of this study was to determine the maximal tolerated dose of thiotepa administered with busulfan 12 mg/kg and melphalan 100 mg/m2 followed by autologous stem cell transplantation in patients with refractory malignancies. Twenty-eight patients with refractory malignancies received high-dose busulfan 12 mg/kg, melphalan 100 mg/m2 and escalating doses of thiotepa 450-550 mg/m2 followed by infusion of cryopreserved autologous peripheral blood stem cells (n = 26) or marrow (n = 2). The maximum tolerated dose was determined to be busulfan 12 mg/kg, melphalan 100 mg/m2 and thiotepa 500 mg/m2. Two of three patients receiving thiotepa 550 mg/m2 experienced grade 3 colitis. Twenty patients were enrolled at the maximum tolerated dose and the incidence of grade 3-4 regimen-related toxicity and mortality was 10% and 5%, respectively. Ninety-five per cent of patients experienced grade 1-2 mucositis, 50% grade 1-2 gastrointestinal toxicity, 35% grade I hepatic toxicity and 20% experienced grade 1-2 skin toxicity. The median time to achieve a granulocyte count of 0.5 x 10(9)/I was 10 days (range 8-20 days) and platelet transfusion independence was 10 days (range 1-26 days). Five of ten patients with stage 4 refractory breast cancer achieved a complete and two a partial remission with a complete response rate of 50% and a overall response rate of 70%. In conclusion, busulfan, melphalan and thiotepa can be administered in high doses with tolerable mucositis as the major side-effect. This combination has significant activity in patients with breast cancer, and phase II studies in patients with breast cancer and other chemotherapy sensitive malignancies are warranted.

Ten patients with aplastic anemia (AA) and seven patients with refractory anemia (RA) were treated with recombinant human granulocyte colony-stimulating factor (rhG-CSF) and erythropoietin (rhEpo) in combination. rhG-CSF (5-20 micrograms/kg) and rhEpo (120-720 U/kg) were administered by s.c. injection three times a week for at least six months, and the administration was continued as maintenance therapy for as long as possible when hematological responses were observed. Six (60%) of the ten AA patients and four (58%) of the seven RA patients showed multilineage responses. Of these responders, six patients achieved trilineage recovery. While all of the responders were dependent on red blood cell transfusions and eight of them required platelet transfusions before treatment, they now no longer need transfusions of either red blood cells or platelets. A median treatment duration of 9 (range 1 to 28) months was required to achieve multilineage recovery. The responders showed an ability to maintain the multilineage recovery for 9+ to 47+ months and to tolerate long-term treatment. These results indicate that the long-term treatment with rhG-CSF and rhEpo may benefit a substantial percentage of patients with AA and RA and provide an optional therapy for these patients.

We report the data of 19 children with neuroblastoma (NB) or Ewing's sarcoma (EW) who had peripheral blood stem cells (PBSCs) harvested after mobilization by: (1) cyclophosphamide (CY) + etoposide + G-CSF, (2) CY + GM-CSF, or (3) G-CSF alone. There were no consistent differences in the number of PBSCs collected following these three different mobilization regimens as assessed by CFU-GM. 17 patients were reinfused with PBSCs after myeloablative therapy and had successful haemopoietic recovery. These results show that in children with solid tumours such as NB or EW a sufficient number of PBSCs can be collected after G-CSF alone, and that PBSCs collected following stimulation by G-CSF alone are as effective in reconstituting haemopoiesis as those collected after mobilizing chemotherapy + HGFs.

CD34(+)-selected hematopoietic progenitor cells are being increasingly used for autotransplantation, and recent evidence indicates that these cells can be expanded ex vivo. Of 15 patients with solid tumors undergoing a phase I/II clinical trial using CD34(+)-selected peripheral blood progenitor cells (PBPCs) after high-dose chemotherapy, we analyzed the frequency of long-term culture-initiating cells (LTCIC) as a measure of transplantation potential before and after ex vivo expansion of CD34+ cells. PBPCs were mobilized by combination chemotherapy and granulocyte colony-stimulating factor (G-CSF). The original unseparated leukapheresis preparations, the CD34(+)-enriched transplants, as well as nonabsorbed fractions eluting from the CD34 immunoaffinity columns (Ceprate; CellPro, Bothell, WA) were monitored for their capacity to repopulate irradiated allogeneic stroma in human long-term bone marrow cultures. We found preservation of more than three quarters of fully functional LTCIC in the CD34(+)-selected fractions. Quantitation of LTCIC by limiting dilution analysis showed a 53-fold enrichment of LTCIC from 1/9,075 in the unseparated cells to an incidence of 1/169 in the CD34+ fractions. Thus, in a single apheresis, it was possible to harvest a median of 1.65 x 10(4) LTCIC per kg body weight (range, 0.71 to 3.72). In addition, in six patients, large-scale ex vivo expansions were performed using a five-factor cytokine combination consisting of stem cell factor (SCF), interleukin-1 (IL-1), IL-3, IL-6, and erythropoietin (EPO), previously shown to expand committed progenitor cells. LTCIC were preserved, but not expanded during the culture period. Optimization of ex vivo expansion growth factor requirements using limiting dilution assays for LTCIC estimation indicated that the five-factor combination using SCF, IL-1, IL-3, IL-6, and EPO together with autologous plasma was the most reliable combination securing both high progenitor yield and, at the same time, optimal preservation of LTCIC. Our data suggest that ex vivo-expanded CD34+ PBPCs might be able to allow long-term reconstitution of hematopoiesis.

The morbidity of high-dose chemotherapy has been considerably reduced by the use of autologous peripheral blood progenitor cell reinfusion. Most studies have used myeloid colony-stimulating factors after stem cell reinfusion, making it difficult to determine the relative contribution of each of these variables to the early recovery of blood cells. The financial implications of colony-stimulating factor use are an area of concern as dose intensification in chemosensitive malignancies is increasingly employed. We have studied 19 consecutive patients receiving high-dose chemotherapy with and without filgrastim (Amgen, granulocyte colony-stimulating factor, G-CSF) after stem cell infusion to examine its effect on the kinetics of blood cell recovery, the complications of myelosuppression and the associated costs. Analysis of the two treatment groups reveals that administration of filgrastim 10 micrograms kg-1 day-1 following stem cell reinfusion does not further accelerate haemopoietic recovery, fails to reduce the incidence of neutropenic fever or antibiotic usage and significantly increases the cost of the procedure. The results of this study do not support the routine use of filgrastim after high-dose chemotherapy and peripheral blood stem cell reinfusion.