Transplantation of hematopoietic stem cells. II: Indications for transplantation of hematopoietic stem cells after myeloablative therapy

The destruction of hematopoiesis and lymphopoiesis by total body irradiation or high dose chemotherapy for the treatment of malignancy can be reversed by the transplantation of allogeneic or autologous hematopoietic stem cells. In primary disorders of bone marrow or immune system, allogeneic stem cells replace deficient cells. Acute leukemias can be cured, with in 50 to 80% disease free survival after 5 to 8 years. The allogeneic graft versus leukemia effect by immunoreactive cells reduces the relapse rate in myeloid and lymphoid malignancies. 40 to 70% of patients with chronic myeloid leukemia remain disease free after more than 5 years. Patients with malignant lymphoma have a 40 to 70% chance of cure with autologous transplantation, which is not increased by allogeneic cells, because of a higher incidence of severe complications. An increasing number of patients without option for cure is treated with the aim of prolonging remission or retarding disease progression, such as in chronic myeloid leukemia, multiple myeloma and certain solid tumors. New studies suggest in breast cancer with axillary lymph node metastases, that adjuvant high dose chemotherapy with autologous stem cell support will significantly improve disease free survival from 30 to over 60% after 3 to 5 years. In congenital metabolic and storage diseases deficient enzymes are substituted by the allogeneic cells. Clinical trials explore the use of stem cell transplantation after myeloablative therapy in autoimmune disorders as well as in gene therapy with transfected hematopoietic stem cells.     

Transplantation of allogeneic peripheral hematopoietic progenitor cells instead of bone marrow

In a pilot study we tested the feasibility and safety of peripheral blood precursor cells instead of bone marrow cells for allogeneic transplantation. 13 patients, 7 male and 6 female between 24 and 52 years of age with hematological malignancies (10 with acute leukemias, 3 with myeloproliferative syndromes-were conditioned for bone marrow transplantation with VP-16, cyclophosphamide and total body irradiation followed by graft-versus-host disease prophylaxis with cyclosporin and methotrexate. Precursor cells were mobilized in the donors by granulocyte colony stimulating factor (G-CSF, Neupogen) 10 micrograms/kg s.c. from day-5 on. A total of 14.05 x 10(8) nucleated cells/kg recipient body weight (range 9.52-20.23 x 10(8)/kg), corresponding 6.82 x 10(6)/kg CD 34+ cells (range 1.43-15.84 x 10(8)/kg) or 113.9 x 10(4) CFU/kg (range 45.15-431.64 x 10(4)/kg) were collected by 3 phereses (1 patient 5 phereses) of 27-45 liters and infused without further manipulation. All patients engrafted with a recovery of total white blood cell count > 1 x 10(9)/l on day 15 (day 10-26) and of platelets > 20 x 10(9)/l on day +18 (day 12-39). 11 of the 12 patients developed aGvHD, 8 with grade II, 3 with grade > or = II. 9 of 13 patients are alive and well +4 to +16 months posttransplant, 3 patients died of aGvHD, one of veno-occlusive disease. These preliminary results confirm the capacity of peripheral blood precursor cells for rapid and complete engraftment in the allogeneic setting. Whether they induce more or equal aGvHD is an open question. Their value in allogeneic transplantation is currently under investigation in prospective randomized trials.     

Engraftment of ex vivo expanded and cycling human cord blood hematopoietic progenitor cells in SCID mice

The ability of human hematopoietic cells to engraft SCID mice provides a useful model in which to study the efficiency of retroviral gene transfer and expression in primitive stem cells. In this regard, it is necessary to determine whether SCID mice can be engrafted by cycling human hematopoietic progenitor cells. Human cord blood cells from 12 different donors were cultured in vitro for 6 days with interleukin-3 and stem cell factor. Phenotypic analysis indicated that hematopoietic cells were induced to cycle and the number of progenitors was expanded, thus making them targets for retroviral gene transfer. The cells were then transferred to SCID mice. Human hematopoietic progenitor cell engraftment was assessed up to 7 weeks later by growth of human progenitor cells in soft agar. After in vitro culture under conditions used for retroviral gene transfer, human cord blood hematopoietic cells engrafted the bone marrow and spleen of SCID mice. Interestingly, cultured cord blood cells engrafted after intraperitoneal but not after intravenous injection. Furthermore, engraftment of cord blood cells was observed in mice receiving no irradiation before transfer of the human cells, suggesting that competition for space in the marrow is not a limiting factor when these cells have been cultured. Administration of human cytokines after transfer of human cord blood cells to SCID mice was also not required for engraftment. Thus, engraftment of SCID mice with human hematopoietic cells cultured under conditions suitable for gene transfer may provide an in vivo assay for gene transfer to early human hematopoietic progenitor cells.     

Engraftment and outcomes of patients receiving myeloablative therapy followed by autologous peripheral blood stem cells with a low CD34+ cell content

Engraftment kinetics after high-dose chemotherapy (HDC) were evaluated in patients receiving autologous peripheral blood stem cell (PBSC) infusions with a low CD34+ cell content. Forty-eight patients were infused with < 2.5 x 10(6) CD34+ cells/kg; 36 because of poor harvests and 12 because they electively received only a fraction of their harvested cells. A median of 2.12 x 10(6) CD34+ cells/kg (range, 1.17-2.48) were infused following one of seven different HDC regimens. All patients achieved absolute neutrophil counts > or = 0.5 x 10(9)/l at a median of day 11 (range, 9-16). Forty-seven patients achieved platelet counts > or = 20 x 10(9)/l at a median of day 14 (range, 8-250). Nine of 47 (19%) had platelet recovery after day 21, 4/47 (9%) after day 100 and one died on day 240 without platelet recovery. Twenty-six patients (54%) died of progressive disease in 51-762 days; 22 (46%) are alive at a median of 450 days (range, 94-1844), 17 (35%) of whom are surviving disease-free at a median of 494 days (range, 55-1263). No patient died as a direct consequence of low blood cell counts. These data demonstrate that PBSC products containing 1.17-2.48 x 10(6) CD34+ cells/kg resulted in relatively prompt neutrophil recovery in all patients but approximately 10% had delayed platelet recovery.     

Engraftment of HLA-matched sibling hematopoietic stem cells after immunosuppressive conditioning regimen in patients with hematologic neoplasias

BACKGROUND AND OBJECTIVE: The main objective of this pilot study was to assess the possibility of achieving engraftment of HLA-matched sibling donor mobilized hematopoietic stem cells after immunosuppressive non-myeloablative therapy. The second objective was to verify whether high-dose therapy with autologous stem cells rescue followed by allografting conditioned by only an immunosuppressive regimen, can be combined in order to achieve the reduction of tumor burden after autografting and the control of residual disease with immune-mediated effects after allografting. DESIGN AND METHODS: To enter the pilot study the patients had to fulfil the following criteria: advanced resistant disease, presence of an HLA matched sibling donor, no general contraindications to stem cell transplantation. Our data refers to 9 patients: Hodgkin's disease (n = 4), non-Hodgkin's lymphoma (n = 2), advanced chronic myelogenous leukemia (n = 2) (one patient with accelerated phase Ph-negative but p190 BCR-ABL gene positive by RT-PCR and one with Ph-positive blastic phase), refractory anemia with excess of blasts t(1;3) (p36;q21) (n = 1). All patients but one received the combined approach. At a median of 40 days (range 30-96), after high-dose therapy and autologous stem cell engraftment, the patients were treated with immunosuppressive therapy consisting of fludarabine and cyclophosphamide (Flu-Cy protocol) and then HLA matched donor mobilized stem cells were infused into the patients. GvHD prophylaxis consisted of cyclosporin and methotrexate. RESULTS: To date, with a median observation period of 4 months (range, 2-10), complete chimerism (100% donor cells) has been achieved in 6 patients. Three patients did not achieve complete chimerism: one patient died of progressive Hodgkin's disease when he reached 55% of donor cells, another patient is now in increasing phase of donor cell engraftment and the last patient (blastic phase-CML) was the only case who appears to have had autologous recovery. Two of the Hodgkin's disease patients, who were in partial remission after autografting, achieved complete remission after allografting and both are disease free 2 and 6 months after. Another Hodgkin's disease patient is alive at 10 months but she has progressive disease. One of the two patients with non-Hodgkin's lymphoma, who achieved partial remission after autografting, obtained complete remission and he is disease free 2 months after allografting. The other patient maintains partial remission obtained after autografting. The accelerated phase-CML patient obtained hematologic and molecular remission; the RAEB patient achieved hematologic and cytogenetic remission. In two patients severe aGVHD (grade II-III) was the single major complication but neither patient died of it. Mild aGVHD was seen in another patient. In only one patient did the ANC decrease to below 1 x 10(9)/L and in no case did platelets decrease below 20 x 10(9)/L. No patients required a sterile room or any red cell or platelet transfusions. INTERPRETATION AND CONCLUSIONS: Immunosuppressive therapy with a Flu-Cy protocol allowed engraftment of HLA-matched sibling donor stem cells without procedure-related deaths; moreover, we have demonstrated that this combined procedure can be pursued in safety in a serious ill population and some of these patients achieved a complete remission. This procedure is not likely to be curative, but a fascinating step along the path to curing these diseases. Of course, the follow-up is too short to document the incidence of cGvHD.     

Expression of an L-selectin ligand on hematopoietic progenitor cells

The process of hematopoiesis is dependent on discrete cell-cell and cell-matrix interactions which are tightly regulated by expression of adhesion molecules. L-selectin, an adhesion protein best known for regulating leukocyte attachment to endothelium, is characteristically expressed on the earliest hematopoietic progenitor cells. Ligands for L-selectin have been extensively characterized on endothelial cells. We recently identified a ligand for L-selectin expressed on the human hematopoietic progenitor cell line KG1a. This molecule is an integral membrane glycoprotein which is structurally different from all ligands previously described. We hypothesize that this molecule may mediate L-selectin-specific adhesive interactions during hematopoiesis. This article discusses the biology of L-selectin and its ligands, and reviews our current understanding of the structure and distribution of the L-selectin ligand expressed on hematopoietic cells.     

Collection of more hematopoietic progenitor cells with large volume leukapheresis in patients with multiple myeloma

We applied reversed phase high performance liquid chromatography for globin chain synthesis analysis in screening for beta-thalassemia. The alpha/non-alpha-globin chain synthesis ratios have been determined in alpha-, beta-, and deltabeta-thalassemia carriers using the classical carboxymethyl cellulose chromatography as the reference method. Reversed phase high performance liquid chromatography is fast, accurate, and reproducible, and may be a suitable alternative for the traditional carboxymethyl cellulose chromatography.     

Acute effects of prechemotherapy filgrastim administration on late hematopoietic progenitor cells

Administration of filgrastim influences the proliferative kinetics of myeloid progenitor cells. Even after it is discontinued, increased levels of cycling of granulocyte precursors are sustained for approximately 4 days. Beginning chemotherapy during this period of enhanced marrow activity can cause great damage to late, and possibly early, progenitor cell pools. Peripheral blood samples were collected from two research study patients who were prospectively randomized to receive filgrastim by different schedules after chemotherapy. The mononuclear cell fraction was analyzed by clonogenic progenitor cell assay and flow cytometry. Ex vivo and clinical findings were correlated with filgrastim and chemotherapy administration times. Although quantitative recovery of circulating neutrophils occurred, a substantial decrease in peripheral blood progenitor cells was observed when chemotherapy was started 72 hours after cessation of filgrastim therapy. Neutrophil recovery alone is not a precise index of short-term marrow granulocyte progenitor status. Starting chemotherapy within 72 hours of filgrastim therapy is biologically, and possibly, clinically relevant.     

Cell cycle analysis and synchronization of pluripotent hematopoietic progenitor stem cells

Hematopoietic stem cells purified from mouse bone marrow are quiescent with less than 2% of Lin- Hoechst(low)/Rhodamine(low) (Lin- Ho(low)/Rho(low)) and 10% to 15% of Lin-/Sca+ cells in S phase. These cells enter proliferative cycle and progress through G1 and into S phase in the presence of cytokines and 5% heat-inactivated fetal calf serum (HI-FCS). Cytokine-stimulated Lin- Ho(low)/Rho(low) cells took 36 to 40 hours to complete first division and only 12 hours to complete each of 5 subsequent divisions. These cells require 16 to 18 hours to transit through G0/G1 period and 28 to 30 hours to enter into mid-S phase during the first cycle. Up to 56% of Lin- Rho(low)/Ho(low) cells are high-proliferative potential (7 factor-responsive) colony-forming cells (HPP-CFC). At isolation, HPP-CFC are quiescent, but after 28 to 30 hours of culture, greater than 60% are in S phase. Isoleucine-deprivation of Lin- Ho(low)/Rho(low) cells in S phase of first cycle reversibly blocked them from entering into second cycle. After the release from isoleucine-block, these cells exhibited a G1 period of less than 2 hours and entered into mid-S phase by 12 hours. Thus, the duration of G1 phase of the cells in second cycle is 4 to 5 times shorter than that observed in their first cycle. Similar cell cycle kinetics are observed with Lin-/Sca+ population of bone marrow cells. Stem cell factor (SCF) alone, in the presence of HI-FCS, is as effective as a cocktail of 2 to 7 cytokines in inducing quiescent Lin-/Sca+ cells to enter into proliferative cycle. Aphidicolin treatment reversibly blocked cytokine-stimulated Lin-/Sca+ cells at G1/S boundary, allowing their tight synchrony as they progress through first S phase and enter into second G1. For these cells also, SCF alone is sufficient for their progression through S phase. These studies indicate a very short G1 phase for stem cells induced to proliferate and offer experimental approaches to synchronize murine hematopoietic stem cells.     

Leptin stimulates the proliferation of murine myelocytic and primitive hematopoietic progenitor cells

Leptin, the product of obese gene, was originally identified as a factor regulating body-weight homeostasis and energy balance. The present study has shown that leptin acts on murine hematopoiesis in vitro. In the culture of bone marrow cells (BMC) of normal mice, leptin induced only granulocyte-macrophage (GM) colony formation in a dose-dependent manner, and no other types of colonies were detected even in the presence of erythropoietin (Epo). Leptin also induced GM colony formation from BMC of db/db mutant mice whose leptin receptors were incomplete, but the responsiveness was significantly reduced. The effect of leptin on GM colony formation from BMC of normal mice was also observed in serum-free culture, and comparable with that of GM-colony-stimulating factor (CSF ). Although leptin alone supported few colonies from BMC of 5-fluorouracil (5-FU)-treated mice in serum-free culture, remarkable synergism between leptin and stem cell factor (SCF ) was obtained in the colony formation. The addition of leptin to SCF enhanced the SCF-dependent GM colony formation and induced the generation of a number of multilineage colonies in the presence of Epo. When lineage (Lin)-Sca-1(+) cells sorted from BMC of 5-FU-treated mice were incubated in serum-free culture, leptin synergized with SCF in the formation of blast cell colonies, which efficiently produced secondary colonies including a large proportion of multilineage colonies in the replating experiment. In serum-free cultures of clone-sorted Lin-c-Kit+Sca-1(+) and Lin-c-Kit+Sca-1(-) cells, although synergism of leptin and SCF was observed in the colony formation from both cells, leptin alone induced the colony formation from Lin-c-Kit+Sca-1(-), but not Lin-c-Kit+Sca-1(+) cells. These results have shown that leptin stimulates the proliferation of murine myelocytic progenitor cells and synergizes with SCF in the proliferation of primitive hematopoietic progenitors in vitro.     

A multicenter study of platelet recovery and utilization in patients after myeloablative therapy and hematopoietic stem cell transplantation

An observational study was conducted at 18 transplant centers in the United States and Canada to characterize the platelet recovery of patients receiving myeloablative therapy and stem cell transplantation and to determine the clinical variables influencing recovery, determine platelet utilization and cost, and incidence of hemorrhagic events. The study included 789 evaluable patients transplanted in 1995. Clinical, laboratory, and outcome data were obtained from the medical records. Variables associated with accelerated recovery in multivariate models included (1) higher CD34 count; (2) higher platelet count at the start of myeloablative therapy; (3) graft from an HLA-identical sibling donor; and (4) prior stem cell transplant. Variables associated with delayed recovery were (1) prior radiation therapy; (2) posttransplant fever; (3) hepatic veno-occlusive disease; and (4) use of posttransplant growth factors. Disease type also influenced recovery. Recipients of peripheral blood stem cells (PBSC) had faster recovery and fewer platelet transfusion days than recipients of bone marrow (BM). The estimated average 60-day platelet transfusion cost per patient was $4,000 for autologous PBSC and $11,000 for allogeneic BM transplants. It was found that 11% of all patients had a significant hemorrhagic event during the first 60 days posttransplant, contributing to death in 2% of patients. In conclusion, clinical variables influencing platelet recovery should be considered in the design and interpretation of clinical strategies to accelerate recovery. Enhancing platelet recovery is not likely to have a significant impact on 60-day mortality but could significantly decrease health care costs and potentially improve patient quality of life.     

Use of flow cytometric CD34 analysis to quantify hematopoietic progenitor cells

This review summarizes our experiments on flow cytometric analysis of CD34 positive mononuclear cells (MNC) and on colony formation of myeloid hematopoietic progenitor cells in the clonogenic assay. We examined MNC isolated by density centrifugation of bone marrow, cord blood and peripheral blood. The latter samples originated either from patients recovering from myelosuppressive treatment who received no growth factors or from patients treated with G-CSF or GM-CSF. We attempted to correlate the results obtained by CD34 analysis with the cloning efficiency determined after a 14 day culture period in the methylcellulose-based clonogenic assay. The highest cloning efficacy (60%-100%) was observed in cord blood, however, a good correlation was found in both untreated and GM-CSF treated peripheral blood samples in which a mean of 50% and 20% of the number of CD34 positive MNC gave rise to myeloid colonies. In bone marrow, the cloning efficacy was generally lower and ranged between 5% and 15%. The lowest values were observed in G-CSF treated peripheral blood in which colonies were grown from only 1%-9% of the CD34+ MNC. Due to the variable numbers of CD34+ lymphoid and/or more committed myeloid precursors which form either no colonies or only clusters, there was a greater variation and a lower cloning efficiency in the latter two cell sources. In conclusion, one colour CD34 analysis of cord blood MNC and untreated or GM-CSF treated peripheral blood MNC provides reliable results with respect to the content of myeloid progenitors. Analysis of bone marrow MNC and G-CSF treated peripheral blood MNC requires two colour staining using CD34 and CD45RA.(ABSTRACT TRUNCATED AT 250 WORDS)     

Purging of mammary carcinoma cells during ex vivo culture of CD34+ hematopoietic progenitor cells with recombinant immunotoxins

Tumor cells have been found in autologous hematopoietic cell transplants used after high-dose chemotherapy. To specifically eliminate contaminating mammary tumor cells during ex vivo expansion of CD34+ hematopoietic progenitor cells, we used recombinant immunotoxins (ITs) directed against cell-surface antigens expressed on mammary carcinoma cells. ITs were expressed from fusion cDNAs combining a single-chain antibody fragment (scFv) directed against the Erb-B2 or epidermal growth factor (EGF) receptors with a truncated Pseudomonas exotoxin A fragment devoid of its cell-binding domain. CD34+ hematopoietic progenitor cells did not express Erb-B2 and EGF receptors as detected by Western blotting. Ex vivo expansion of total hematopoietic cells or of colony-forming cells from CD34+ progenitors in the presence of stem-cell factor (SCF), interleukin-1 (IL-1), IL-3, IL-6, and erythropoietin (Epo) was not affected when ITs were added to the cultures. In contrast, MDA-MB 453 and MCF-7 mammary carcinoma cells were depleted in a dose- and time-dependent manner by more than 3 log in coculture with CD34+ cells over a period of 7 days in the presence of 100 to 1,000 ng/mL of anti-Erb-B2 IT. This included elimination of the subpopulations with regrowth potential. Similarly, addition of either anti-Erb-B2 or anti-EGF receptor ITs to primary breast cancer cells isolated from patients with metastatic disease resulted in elimination of cytokeratin-positive cells in seven of seven samples. ITs are highly efficient and convenient to use for the depletion of mammary tumor cells during ex vivo expansion of hematopoietic progenitor-cell autografts.     

Biologic and phenotypic analysis of early hematopoietic progenitor cells in umbilical cord blood

Umbilical cord blood (UCB) is an attractive potential alternative to bone marrow (BM) as a source of hematopoietic progenitor cells since the number of progenitors in UCB is similar or even greater than that in normal BM. It was the aim of the present study to analyze the degree of immaturity of UCB progenitor cells. UCB mononuclear (MNC) and/or CD34+ cells were tested for surface antigen phenotype, expression of cytokines receptor, effect of stem cell factor (SCF) on colony growth, resistance to mafosfamide and replating potential. We have found that 34.9 +/- 3.4% and 77.9 +/- 2.6% of UCB CD34+ cells did not express CD38 and CD45RA antigens, respectively, suggesting that UCB contains a high proportion of immature progenitor cells. By means of three-color analysis, the receptor for SCF was detected on the majority of the CD34+ HLA-DR+ subpopulation; in fact, 81.8% +/- 4.3% of CD34+ HLA-DR+ cells were defined as SCF(low) and 8.1 +/- 1.5% as SCF(high). Colony growth of MNC and CD34+ cells was enhanced by the addition of SCF to methylcellulose mixture, resulting in a statistically significant increase in CFU-GM and CFU-GEMM but not in BFU-E numbers. UCB progenitor cells showed a higher resistance to mafosfamide treatment, in comparison to BM; the addition of SCF to the culture medium resulted in a statistically significant increase in mafosfamide concentration required to inhibit 95% of colony growth (P < or = 0.05). Moreover, as shown by single colony transfer assays, the presence of SCF in primary cultures promoted a significantly higher replating potential for both untreated (42 +/- 3.3% vs 21 +/- 4.6%, P < or = 0.018) and mafosfamide-treated samples (62 +/- 5.6% vs 44 +/- 6.1%, P < or = 0.018). In conclusion, UCB is a source of progenitor cells with immature characteristics in terms of surface antigen expression, distribution of SCF receptor, resistance to mafosfamide and replating potential. Therefore, UCB progenitor cells represent an ideal candidate population for experimental programs involving gene transfer and ex vivo stem cell expansion.     

Functional expression of Fas antigen (CD95) on hematopoietic progenitor cells

We investigated the expression of an apoptosis-associated antigen (Fas) (CD95) on hematopoietic progenitor cells in the presence or absence of interferon-gamma (IFN-gamma) and/or tumor necrosis factor-alpha (TNF-alpha). CD34+ cells freshly isolated from bone marrow did not express Fas. However, IFN-gamma and/or TNF-alpha induced the expression of both the mRNA of Fas and Fas itself in a dose-dependent fashion on the surface of CD34+ cells after 48 hours of serum-free culture. IFN-gamma and TNF-alpha had a synergistic effect on the induction of Fas, when both cytokines were added to the culture. The TNF-alpha-induced Fas expression is mediated by p55 TNF-alpha receptor. CD34+ cells cultured in medium alone or with stem cell factor (SCF) showed some slight expression of Fas. When anti-Fas antibody (IgM) was added to CD34+ cells after the induction of Fas expression, CD34+ cells underwent apoptosis, as shown by a decrease in the number of viable cells, morphologic changes, the induction of DNA fragmentation, and a decrease in the number of colony-forming cells (CFC) including colony-forming unit granulocytes/macrophages (CFU-GM) and burst-forming unit erythroids (BFU-E). These observations indicate that IFN-gamma and/or TNF-alpha, well known as negative hematopoietic regulators, induce functional Fas on hematopoietic progenitor cells. The suppression of hematopoiesis by negative hematopoietic regulators may be mediated in part by Fas induction.     

Mobilization of peripheral blood progenitor cells by disease-specific chemotherapy in patients with soft tissue sarcoma

We investigated peripheral blood progenitor cell (PBPC) mobilization by disease-specific chemotherapy in patients with metastatic soft tissue sarcoma (STS). Nine patients, five females and four males, aged 12-51 years, pretreated by one to nine courses of cytotoxic chemotherapy, underwent STS-specific mobilization followed by G-CSF at 5 microg/kg/day. PBPC were collected by 19 conventional-volume aphereses (8-12 l) with one to four procedures in individual patients. Leukaphereses started on median day 15 (range 13-18) from the first day of mobilization chemotherapy at medians of 25.8 x 10(3) WBC/microl (6.8-46.9), 3.5 x 10(3) MNC/microl (1.1-8.8), 122 x 10(3) platelets/microl (72-293) and 30.7 CD34+ cells/microl (6.7-207.8). Cumulative harvests resulted in medians of 4.6 x 10(8) MNC/kg (3.0-6.4), 2.9 x 10(6) CD34+ cells/kg (1.1-11.1) and 12.0 x 10(4) CFU-GM/kg (2.0-37.8). Eight patients underwent high-dose chemotherapy (HDCT) followed by PBPC rescue. Seven patients recovered hematopoiesis at medians of 12 days (8-15) for ANC >0.5 x 10(3)/microl and 14 days (8-27) for platelets >20 x 10(3)/microl. One patient, who received 1.6 x 10(6) CD34+ cells/kg, exhibited delayed ANC recovery on day +37 and failed to recover platelets until hospital discharge on day +55. We conclude that in patients with metastatic STS, who are pretreated by standard chemotherapy, PBPC can be mobilized by a further course of STS-specific chemotherapy plus G-CSF. One to four conventional-volume aphereses result in PBPC autografts that can serve as hematopoietic rescue for patients scheduled for HDCT.     

High-dosage chemotherapy and the autologous transplantation of peripheral hematopoietic progenitor cells in breast cancer: the initial results, analysis of toxicity and the necessary support means

BACKGROUND: In the last years high dose chemotherapy (HDC) schedules have been developed with autologous bone marrow transplantation (ABMT) which are very effective in breast cancer. Expectation has been raised concerning the cure of a subgroup of patients with metastatic breast cancer and the improvement of prognosis in high risk stages II and III. METHODS: CTCb (cyclophosphamide 6 g/m2, thiotepa 500 mg/m2 and carboplatin 800 mg/m2) was administered with autologous peripheral hematopoietic progenitor cells transplantation (TACPHP) and granulocytic colony stimulating factor (G-CSF) 5 micrograms/kg/day to 27 patients with breast cancer: 9 in stage IV in complete remission, 12 in stage II with > or = 10 affected lymph nodes and 6 in stage III. RESULTS: No toxic deaths were reported. The median time to achieve > or = 0.5 x 10(9) neutrophils/l was 8 days, to > or = 20 x 10(9) platelets/l 9 days and to > or = 50 x 10(9) platelets/l 12 days. Fever was observed in 85% of the patients although its median duration was of only one day. Extrahematologic toxicity was moderate with grade III nausea/vomiting in 48% of patients, grade III mucositis in 22%, grade III hepatitis in 19%, and grade III diarrhea in 4%. No grade IV toxicity was observed. The median follow-up is still short (10 months, range: 2-25). All the patients maintain normal hematologic peripheral blood counts and only 4 (in stage IV) have relapsed. CONCLUSIONS: The slight extrahematologic toxicity observed in the high dose chemotherapy with cyclophosphamide, thiotepa and carboplatin, and the rapid hematologic recovery provided by the TACPHP and G-CSF allow the above schedule to be administered with moderate toxicity and no mortality. This low toxic profile leads to the possibility of future trials with this chemotherapy schedule in other subgroups of patients with breast cancer.     

Collection of allogeneic peripheral blood progenitor cells by two protocols on an apheresis system

BACKGROUND: Granulocyte-colony stimulating factor-mobilized allogeneic peripheral blood progenitor cells (PBPCs) are replacing bone marrow in transplantation for the treatment of several hematologic malignancies. The advantages of PBPCs are offset by the donor-associated disadvantages of granulocyte-colony stimulating factor side effects and the risk of apheresis-like platelet loss. STUDY DESIGN AND METHODS: For each individual, the first donation of allogeneic PBPCs by apheresis on the Spectra, using either the standard protocol Version 4.7 (45 donors, [Version 4.7]) or the AutoPBSC (60 donors, [AutoPBSC]) was compared. Between July 1995 and May 1996, all donors enrolled underwent Version 4.7 apheresis. Since May 1996, the majority of donors underwent AutoPBSC apheresis. For statistical analysis, only data from the first apheresis for each individual donor was considered for independent values. RESULTS: These results indicate a similar collection efficiency for CD34+ cells in the first apheresis of each donor (54% Version 4.7 vs. 53% AutoPBSC, p = 0.8). The apheresis time was longer with the AutoPBSC (233 min vs. 251 min, p = 0.005), whereas the loss of platelets was significantly lower (p < 0.001) with the AutoPBSC (28% vs. 19%). The mean number of CD34+ cells collected in the first apheresis component was 4.0 x 10(8) (Version 4.7) versus 3.8 x 10(8) (AutoPBSC). CONCLUSION: Both apheresis protocols collect sufficient numbers of PBSCs for allogeneic transplantation. The AutoPBSC operates in a fully automatic fashion, avoiding manual adjustment and interindividual variations. The loss of platelets is lower with AutoPBSC than with Version 4.7, but the apheresis time is slightly longer.     

Interleukin-12 preserves the graft-versus-leukemia effect of allogeneic CD8 T cells while inhibiting CD4-dependent graft-versus-host disease in mice

We have recently demonstrated that a single injection of 4,900 IU of interleukin-12 (IL-12) on the day of bone marrow transplantation (BMT) markedly inhibits acute graft-versus-host disease (GVHD) in a fully major histocompatibility complex plus minor antigen-mismatched BMT model (A/J --> B10, H-2(a) --> H-2(b)), in which donor CD4(+) T cells are required for the induction of acute GVHD. We show here that donor CD8-dependent graft-versus-leukemia (GVL) effects against EL4 (H-2(b)) leukemia/lymphoma can be preserved while GVHD is inhibited by IL-12 in this model. In mice in which IL-12 mediated a significant protective effect against GVHD, marked GVL effects of allogeneic T cells against EL4 were observed. GVL effects against EL4 depended on CD8-mediated alloreactivity, protection was not observed in recipients of either syngeneic (B10) or CD8-depleted allogeneic spleen cells. Furthermore, we analyzed IL-12-treated recipients of EL4 and A/J spleen cells which survived for more than 100 days. No EL4 cells were detected in these mice by flow cytometry, tissue culture, adoptive transfer, necropsies, or histologic examination. Both GVL effects and the inhibitory effect of IL-12 on GVHD were diminished by neutralizing anti-interferon-gamma (IFN-gamma) monoclonal antibody. This study demonstrates that IL-12-induced IFN-gamma production plays a role in the protective effect of IL-12 against GVHD. Furthermore, IFN-gamma is involved in the GVL effect against EL4 leukemia, demonstrating that protection from CD4-mediated GVHD and CD8-dependent anti-leukemic activity can be provided by a single cytokine, IFN-gamma. These observations may provide the basis for a new approach to inhibiting GVHD while preserving GVL effects of alloreactivity.