HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints/Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Anderlini, P. Articles by Körbling, M. Search for Related Content PubMed PubMed Citation Articles by Anderlini, P. Articles by Körbling, M.

The Use of Mobilized Peripheral Blood Stem Cells from Normal Donors for Allografting

The University of Texas M.D. Anderson Cancer Center, Department of Hematology, Section of Blood and Marrow Transplantation, Houston, Texas, USA

Key Words. Allogenic peripheral blood stem cell transplantation • Stem cell mobilization • Recombinant human granulocyte colony-stimulating factor (rHuG-CSF) • Graft-versus-host disease • Graft-versus-leukemia

Dr. Martin Körbling, University of Texas M.D. Anderson Cancer Center, Department of Hematology, Box 24, 1515 Holcombe Boulevard, Houston, TX 77030, USA.

	Abstract

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Peripheral blood stem cells (PBSCs) are gaining increasing acceptance as an alternative to bone-marrow (BM)-derived stem cells for allografting. Although scarce under steady-state conditions, CD34⁺ progenitor cells can be effectively mobilized into the peripheral blood (PB) in the vast majority of normal donors with a brief (3-4 days) course of recombinant human (rHu)G-CSF. Those cytokine-peripheralized progenitor cells and, among them, pluripotent stem cells, are collected by apheresis in sufficient amounts to achieve complete and permanent alloengraftment after myeloablative treatment in patients with primarily malignant hematologic disorders. The short-term tolerability profile of PBSC mobilization and apheresis in normal donors appears to be acceptable, although continued monitoring is necessary to ensure long-term safety. When compared with BM progenitor cells, mobilized PBSCs seem to exhibit a more primitive phenotype and a different clonogenic potential. The impact of factors affecting the efficiency of PBSC mobilization, such as rHuG-CSF dose, duration of cytokine treatment, and, to a lesser extent, donor age is now being recognized. Potential ways to optimize and possibly "engineer" PBSC collection, such as the use of cytokine/chemokine combinations (e.g., thrombopoietin, stem cell factor, etc.) and monoclonal antibodies directed against integrin receptors on CD34⁺ progenitor cells, are now being explored as well. In the clinical setting, engraftment after PBSC allografting is rapid and probably faster than after BM allografting. PBSC allografting seems to be associated with an incidence and severity of acute graft-versus-host disease (GVHD) comparable to the ones observed after BM allografting, although the incidence of chronic GVHD after allogeneic PBSC transplantation is still controversial. The infusion of a larger number of lymphoid cells appears to translate into a more rapid immunologic recovery and may lead to an enhanced graft-versus-leukemia effect. The collection of large numbers of mobilized PBSCs should provide ample opportunities for graft engineering and gene therapy. PBSCs may eventually replace, at least in part, BM as the preferred source of stem cells for both auto- and allotransplantation.

	Introduction

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Complete and permanent reconstitution of a hematopoietic system which is myeloablated by chemo/radiotherapy depends on the transplantation of progenitor cells that fulfill the following criteria:

• indefinite self-renewal potential
  
• pluripotential characteristics
  
• CD34 antigen present on surface
  
• initiate long-term bone marrow culture.
  

Cell surface molecules that, among others, are used to characterize primitive and pluripotent stem cells include HLA class II (DR) antigens [1], CD38 [2], and Thy-1 (Cdw90) [3]. CD34⁺ cells that do not express the CD38 antigen (approximately 1% of CD34⁺ cells) [2], for example, are considered a primitive progenitor cell population with stem cell characteristics. Those early progenitor cells are known to continuously migrate under steady-state conditions between extravascular marrow sites and circulation [4]. With cytokine treatment alone or in combination with chemopriming, progenitor cells and, among them, stem cells are expanded in vivo and shifted into circulation, and thus available for harvest by continuous-flow apheresis.

In the following, the state-of-the-art stem cell mobilization techniques as well as new developments in stem cell peripheralization techniques are described with focus on normal blood stem cell donors whose unperturbed hematopoietic system allows us to study the effects of cytokine treatment in particular.

	Blood Stem Cell Collection from Patients Versus Normal, Patient-Related or Unrelated Donors

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Under steady-state conditions, the peripheral blood (PB) CD34⁺ cell concentration in normal subjects is on the average 0.06% among circulating nucleated cells [5]. The absolute number of circulating CD34⁺ cells in normal individuals has been reported to be 3.8 (±0.8 SD) x 10³/ml PB (n = 14) [5] or 3.8 (±3.2 SD) cells/µL PB (n = 10) [6]. This is considered insufficient to provide a CD34⁺ cell engraftment dose by single or multiple apheresis in a reasonable time period. A temporary peripheralization of CD34⁺ cells and subsets into the circulating blood is widely used to significantly increase the yield of blood stem cells, thus minimizing the number of aphereses needed to achieve a CD34⁺ engraftment dose.

Harvesting of Blood Stem Cell Autografts
Stem cell peripheralization and harvesting for autografts is practiced differently from allografts. Induction of a progenitor cell rebound by using conventional-dose intensification regimens together with recombinant human (rHu) G-CSF treatment is widely used for collection of the patient's own progenitor cells. The following "chemopriming" regimens are used in our institution:

• high-dose cyclophosphamide (4 g/m²) for patients with breast cancer or multiple myeloma,
  
• ifosfamide, etoposide for patients with non-Hodgkin's lymphoma or Hodgkin's disease,
  
• cyclophosphamide, etoposide, cisplatin (CVP) for patients with solid tumors (e.g., breast cancer).
  

To enhance the induction of a PB progenitor cell rebound, rHuG-CSF treatment is started shortly after completion of chemopriming treatment and continued until completion of apheresis (5 to 12 µg/kg/d). Stem cell collection is started when the WBC count has recovered to approximately 1000/µl after chemopriming.

It should be noted that the kinetics of cell recovery after chemopriming varies enormously depending on such parameters as:

• length and intensity of prior chemotreatment
  
• disease stage (i.e., bone marrow involvement)
  
• disease category
  
• chemopriming regimen.
  

It is also noteworthy that in patients whose marrow stem cell pool is significantly diminished by prior chemotherapy, an additional chemopriming regimen might impair rather than induce stem cell peripheralization. Stem cell toxic chemotherapeutic agents such as busulfan, doxorubicin, melphalan, thiotepa, and possibly fludarabine (and others) should not be part of a chemopriming regimen. On the other hand, cyclophosphamide is considered the ideal chemopriming drug with the least stem cell toxicity, although cardiotoxicity (dose > 4 g/m²) [7] and hemorrhagic cystitis are the well-known dose-limiting extramedullary side effects.

Harvesting of Blood Stem Cell Allografts
Recent studies have evaluated the use of rHuG-CSF (filgrastim)-mobilized peripheral blood stem cells (PBSC) as an alternative to bone marrow (BM) for allografting. There is already sufficient experience with patient-related and HLA-matched stem cell donors, although stem cell donation by unrelated donors as part of the North American National Marrow Donor Program or another international registry is presently being discussed and/or has been performed in a limited number of cases [8].

Peripheralization of hematopoietic progenitor cells by rHuG-CSF is the treatment of choice in normal stem cell donors and is superior to rHuGM-CSF [9, 10]. Novel cytokine combinations and chemokines are under investigation, as well as monoclonal antibodies, which alter the interaction between CD34⁺ progenitor cells and extracellular matrix molecules.

Safety and potential long-term effects of cytokine treatment in normal donors are of primary importance—issues that are now being addressed by individual institutions as well as by national and international registries.

	Cell Mobilization in Normal Adult Donors Using rHuG-CSF

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Effect of rHuG-CSF Treatment on the Peripheralization of WBC, Polymorphonuclear, Lymphocytes, and CD34⁺ Cells and Subsets
To assess the effects of rHuG-CSF (12 µg/kg/d) on the peripheralization of hematopoietic progenitor cells and lymphoid subsets, we studied a cohort of 41 normal blood stem cell donors. After three days of rHuG-CSF treatment, the WBC, polymorphonuclear, and lymphocyte concentrations in the donor's PB exceeded baseline by 6.4-, 8.0- and 2.2-fold, respectively [5]. A similar increase of T lymphocytes by day 3 of 16 µg/kg/d rHuG-CSF has been reported by Weaver et al. [11], namely 1.5 to 2.0 times over baseline. On the other hand, PB CD34⁺ cells and primitive subsets such as CD34⁺ Thy-1^dim, and CD34⁺ Thy-1^dim CD38^– cells increased by 16.3-fold, 24.2-fold and 23.2-fold, respectively, suggesting a selective peripheralization effect of rHuG-CSF on hematopoietic progenitor cells and, in particular, on their more primitive stem cell subsets [5]. In normal donors, a five-day course of G-CSF increased the clonogenic potential of CD34⁺ cells and shifted the phenotype of long-term culture-initiating cells from CD34⁺CD38^–/dim to CD34⁺CD38^bright [12].

When performing serial-flow cytometric evaluation of CD34⁺ subsets in either rHuG-CSF alone or combined rHuG-CSF/rHuGM-CSF mobilized apheresis products, the relative proportion of CD34⁺ cells expressing a myeloid phenotype (CD13⁺, CD33⁺ and CD45RA^–) increases, whereas the relative proportion of CD34⁺ cells with a lymphoid phenotype (CD34⁺ CD10⁺) decreases [13]. When compared with the CD34⁺ progenitor cell profile in the BM, G-CSF mobilization in normal individuals causes a substantial increase in the percentage of circulating CD34⁺ CD13⁺ and CD34⁺ CD33⁺ cells (myeloid precursors) and a decrease in the percentage of circulating CD34⁺ CD10⁺ and CD34⁺ CD19⁺ cells (B lymphocyte precursors) [14].

Kinetics of CD34⁺ Cells and Subsets under rHuG-CSF Mobilization Treatment
The kinetics of WBC and progenitor cell subsets under rHuG-CSF treatment is quite uniform in an unperturbed, normal hematopoietic system, although a remarkable interindividual variability in the degree of progenitor mobilization has become evident [6, 14]. When monitored over six days on a daily basis under rHuG-CSF treatment (12 µg/kg/d), the kinetics of circulating CD34⁺ cells and subsets paralleled each other, reaching a plateau at day 4 (day 1 = first day of cytokine treatment). Based on those data and data reported by Tjønnfjord et al. [14] using 10 µg/kg/d rHuG-CSF, the most favorable day for stem cell collection would appear to be day 4 or day 5. Continuation of rHuG-CSF administration beyond a 5-day course leads to a decline in the mobilization of CD34⁺ progenitors [15].

Duration of rHuG-CSF Mobilization and Apheresis Yield of CD34⁺ Progenitor Cells and Lymphoid Subsets
The duration of rHuG-CSF mobilization treatment predicts for the leukapheresis yield of CD34⁺ progenitor cells. We studied 77 normal donors who underwent stem cell apheresis for HLA-matched, related recipients beginning on day 4 (n = 45) or day 5 (n = 32) of rHuG-CSF treatment (12 µg/kg/d). Both cohorts were comparable for age, weight, and blood volume processed by apheresis, and target CD34⁺ cell dose of 4 x 10⁶/kg of recipient body weight to be collected. The day 5 schedule allowed a more consistent achievement of target cell dose with one apheresis, and resulted in the initial collection of a significantly larger number of CD34⁺ cells. There was no statistically significant difference in the apheresis yield of lymphoid subsets or natural killer cells, although a trend towards a higher CD3⁺ lymphocyte yield was found [16].

Dose-Dependent Mobilization of CD34⁺ Progenitor Cells
It has been shown that, at least for rHuG-CSF doses up to 10 µg/kg/d, a dose-response relationship exists between rHuG-CSF dose and degree of mobilization of CD34⁺ progenitor cells [15, 17]. Although rHuG-CSF doses up to 24 µg/kg/d have been employed [18], experience with these doses is limited and it is unclear whether they will prove to be necessary or cost-effective for achieving the collection of an "adequate" alloengrafting CD34⁺ cell number.

A recent report has suggested that the glycosylated form of rHuG-CSF (lenograstim) may be more effective in mobilizing CD34⁺ progenitor cells in normal subjects than the nonglycosylated one (filgrastim) [19].

	Stem Cell Mobilization in Pediatric Donors

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Given the promising data reported with clinical trials on allogeneic blood stem cell transplantation in adults and the potential advantage to the donor over a BM harvest under general anesthesia, collection of PBSCs in normal children is an appealing approach.

In the autologous transplant setting, rHuG-CSF treatment at a dose ranging from 5 to 10 µg/kg/day, combined with chemopriming for transient stem cell peripheralization and collection, is well-tolerated in small children [20, 21]. As compared with adverse effects of rHuG-CSF mobilization treatment in normal adult stem cell donors reported by us [22], normal pediatric donors seem to tolerate rHuG-CSF treatment up to 12 µg/kg/day as well.

Venous access in small children providing sufficient blood flow is the major limiting factor for apheresis. To ensure an adequate and consistent blood flow rate of 20 ml/min and more during apheresis, Takaue et al. [21] successfully used a temporary radial artery catheter for blood withdrawal and return through a peripheral vein.

In a series of five allogeneic blood stem cell transplantations using pediatric donors between the ages of 4 and 13 years, we processed a median of 2.2 times the donor's total blood volume per apheresis, which provided a sufficient CD34⁺ cell yield at an acceptable time period (two to three hours). The mean CD34⁺ cell yield per kilogram of donor body weight and per liter of donor blood processed was 128 x 10⁴ in these five children [23], as compared with 63 x 10⁴ for adult donors [5]. As shown in an eight-year-old boy, one single apheresis under rHuG-CSF mobilization treatment was sufficient to collect a CD34⁺ alloengraftment dose of 4 x 10⁶/kg for his father who had been diagnosed with advanced-stage chronic myelogenous leukemia, despite the substantial body weight discrepancy between the pediatric donor (27 kg) and adult recipient (93 kg) [23].

Pediatric blood stem cell collection from normal donors is feasible and safe with adequate cell doses for children or even for adult recipients. Engraftment characteristics and clinical outcome appear comparable so far to the ones achieved with adult PBSC allotransplantation.

	Mobilized Blood-Derived Stem Cells as Compared to Marrow-Derived Stem Cells

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Malcolm Moore [24] compared the ex vivo expansion potential of BM CD34⁺ cells with cyclophosphamide and rHuG-CSF-mobilized PB CD34⁺ cells obtained from previously untreated ovarian cancer patients. In a sequential 7-day delta assay with interleukin (IL-) 1, IL-3 and c-kit ligand stimulation, the expansion rate of mobilized PB CD34⁺ cells at day 21 was reported to be 5.4 times higher than that of steady-state BM CD34⁺ cells, indicating a significantly higher clonogenicity of mobilized PB progenitor cells.

When compared by limiting dilution analysis, long-term culture-initiating cells in BM and rHuG-CSF-mobilized apheresis products, the median proportions of cells generating hematopoietic foci from unfractionated mononuclear cells at five and eight weeks, respectively, were 1:13,314 and 1:33,949 for BM, and 1:10,302 and 1:12,891 for apheresis products. This data indicates a proportionally higher hematopoietic stem cell activity in mobilized apheresis products [25].

We performed flow cytometric analyses on rHuG-CSF-mobilized PBSC allografts from 41 normal donors and compared it with BM allografts from 43 normal donors. The CD34⁺ cell yield of PBSC allografts exceeded that of BM allografts by 3.7-fold and that of lymphoid subsets by 16.1-fold (CD3⁺), 13.3-fold (CD4⁺), 27.4-fold (CD8⁺), 11.0-fold (CD19⁺), and 19.4-fold (CD56⁺CD3^–) [5].

	Stem Cell Mobilization Using Cytokine/Chemokine Combinations

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Combined rHuG-CSF and Recombinant Human Thrombopoietin (rHuTPO)
rHuTPO is a growth factor that stimulates the proliferation and differentiation of megakaryocytic progenitor cells which induces the full maturation of megakaryocytes and release of platelets [26]. As reported by Molineux et al. [27], irradiated mice that received PBSCs mobilized by PEGylated recombinant human megakaryocyte growth and development factor (MGDF) showed a significantly reduced period of thrombocytopenia (<100,000/µl) (four or five days) as compared with unmobilized PBSC transplantation (nine days). rHuMGDF also modestly stimulates the mobilization of myeloid progenitor cells, and rHuMGDF-mobilized PBSCs effect accelerated recovery of platelets when transplanted [27].

A combined mobilization treatment with rHuG-CSF and rHuTPO is expected to increase both circulating myeloid and megakaryocytic progenitor cells which, after collection and transplantation, might shorten the post-transplant period of cytopenia including thrombocytopenia and, thus, obviate the need for platelet transfusions. A first phase I clinical trial is ongoing in our institution to evaluate the mobilizing effect of in vivo administration of both rHuG-CSF and rHuTPO on circulating hematopoietic and megakaryocytic progenitor cells (CD34⁺ CD41a⁺) for collection by apheresis and transplantation.

Combined rHuG-CSF and IL-3
Combined treatment with rHuG-CSF and rHuIL-3 has been reported to further increase circulating progenitor cells as compared with rHuG-CSF treatment alone [28, 29]. rHuG-CSF alone (5 µg/kg/d over five days) increased the number of circulating colony forming units-granulocyte/macrophage (CFU-GM) over baseline by 21-fold. Treatment with IL-3 (5 µg/kg/d) over seven days followed by rHuG-CSF at the same dose level and time period further increased the circulating CFU-GM level by 56-fold over baseline. In a study on normal volunteers, a sequential schedule with a 4-day course of rHuIL-3 (5 µg/kg/d) followed by a 7-day course of rHuG-CSF (5 µg/kg/d) provided the best mobilization results [29]. It is noteworthy that IL-3 treatment alone (5 µg/kg/d over seven days) did not mobilize progenitor cells, whereas in rhesus monkeys an increased number of circulating CFU-GM by about 10-fold was reported [30].

Human Macrophage Inflammatory Protein (MIP-1)
MIP-1 is considered a potential myeloprotective cytokine based on its myelosuppressive and cycle inhibitory functions [31]. As reported by Lord et al. [32], MIP-1 also induces a rapid mobilization effect on early progenitor cells into circulation in mice. In a phase I clinical trial, the administration of BB10010, a genetically engineered and stable variant of MIP-1, at 5 or 10 µg/kg significantly reduced cycling rates of BM progenitor cells, as well as BM concentration, but increased the number of circulating progenitor cells by between 2.6- and 4.1-fold over baseline [33].

IL-1
IL-1 is a newly studied compound for potential stem cell mobilization. As reported in mice, IL-1 administration (1 µg) increases the number of circulating CFU-GM by 30-fold over baseline. Transplantation of IL-1-mobilized blood progenitor cells resulted in long-term donor chimerism [34].

Combined rHuG-CSF and Recombinant Methionyl Human Stem Cell Factor (r-metHuSCF)
While r-metHuSCF alone exerts little effect on in vitro colony formation of normal BM progenitor cells, the combination of r-metHuSCF with GM-CSF, G-CSF or IL-3 synergistically increases colony formation [35]. As shown by Andrews et al. in nonhuman primates [36], low-dose rHuSCF treatment in combination with rHuG-CSF resulted in a 14-fold higher yield of progenitor cells contained in the apheresis product as compared with rHuG-CSF administration alone. WBC, polymorphonuclear cells, and platelets engrafted significantly faster when using the rHuSCF and rHuG-CSF-treated blood stem cell autograft. Several clinical phase I/II trials have been reported to assess the ability of r-metHuSCF in combination with rHuG-CSF to mobilize stem cells in patients with solid tumors or malignant hematologic disorders. In patients with advanced-stage breast cancer, a combined rHuSCF (10 µg/kg/day) and rHuG-CSF (10 µg/kg/day) resulted in a fourfold increase in the percentage of CD34⁺ cells in the apheresis product as compared with rHuG-CSF treatment (10 µg/kg/day) alone [37]. A rHuSCF dose of 20 µg/kg/day in combination with 10 µg/kg/day rHuG-CSF seems to be the appropriate dose range for stem cell mobilization.

	Matrix Molecule Interactions and Stem Cell Mobilization

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Combined rHuG-CSF and Anti-VLA-4 Monoclonal Antibody
Hematopoietic progenitor cells predominantly interact with the extracellular matrix molecule fibronectin through expression of cell-surface receptors belonging to the integrin family. The 4ß1 integrin (very late activation antigen-4 [VLA-4]) and the 5ß1 integrin (very late activation antigen-5 [VLA-5]) receptors are the principal ones through which hematopoietic progenitor cells adhere to fibronectin [38, 39].

Recently, Papayannopoulou and Nakamoto [40] reported a preclinical study in primates using anti-VLA-4 monoclonal antibody (anti-CD49d) to peripheralize hematopoietic progenitor cells. Daily injections of anti-VLA-4 for four days resulted in an increase of PB CFU-GM concentration by 8- to 100-fold over baseline 24 hours after injection, and an 18- to greater than 200-fold increase of BFU-E PB concentration.

Anti-VLA-4 treatment additively augmented peripheralization of progenitors in animals pre-treated with rHuG-CSF for five days. The 5-day rHuG-CSF treatment increased the PB CFU-GM from a baseline concentration of 89 per ml up to 2,000 per ml. After two additional injections of anti-VLA-4 on days 6 and 7, there was a significant increase in CFU-GM beyond the level observed at day 5 of rHuG-CSF, from 2,000 per ml to 13,000 per ml. This increase was maintained for about three days after the last anti-VLA-4 treatment and occurred while the WBC concentration was decreasing. In contrast with rHuG-CSF alone, there was a significant increase in BFU-E, circulating CFU-erythroid, and nucleated red blood cells.

It is believed that some cytokines, including rHuG-CSF, also interfere with the adhesive properties of ß1 integrins on hematopoietic progenitor cells [34] thus providing a potentially additive effect to anti-VLA-4 monoclonal antibody treatment.

	Factors Affecting Mobilization of CD34+ Cells in Normal Donors Treated with rHuG-CSF

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
In an effort to elucidate factors affecting mobilization in normal donors and stem cell yield by apheresis, we evaluated the CD34⁺ cell yield from the first day of apheresis in 119 donors who underwent apheresis on days 4-6 of rHuG-CSF treatment (12 µg/kg/day). The CD34⁺ cell yield was significantly lower in donors greater than 55 years of age, or who were not obese. There was also a weak correlation between CD34⁺ cell yield and age, baseline WBC count, pre-apheresis WBC count, and pre-apheresis mononuclear cell count. Twenty-one (18%) donors were considered poor mobilizers, yielding less than 20 x 10⁶ CD34⁺ cells/liter blood processed. In the multivariate analysis, the only significant risk factor for inferior mobilization was age greater than 55 years, which conferred a 3.8-fold increased risk (p = 0.04). As poor mobilizers occurred in all age groups, however, the predictive value (and clinical usefulness) of the model was limited [41].

	Engraftment Characteristics following Allogeneic Transplantation of rHuG-CSF-Mobilized PBSCs Versus Steady-State BM

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
We evaluated the kinetics of hematopoietic reconstitution, early mortality, and the development of acute graft-versus-host disease (GVHD) after HLA-matched allogeneic transplantation of rHuG-CSF-mobilized PBSC as compared with BM allografts. Three cohorts of patients were analyzed: cohort I (n = 30) received a BM allograft and was treated with Cyclosporine-A + Methotrexate for GVHD prophylaxis. Cohort II (n = 19) received a BM allograft as well, but was prophylactically treated with Cyclosporine-A + Methylprednisolone. Cohort III (n = 25) received a blood stem cell allograft with the same anti-GVHD prophylaxis as cohort II. rHuG-CSF was given to all patients after transplant to enhance hematopoietic reconstitution. Whereas the time to ANC > 500/µl was not different between BM allograft cohort II and blood stem cell allograft cohort III receiving the same non-Methotrexate-containing anti-GVHD prophylaxis (9 and 10 days, respectively), platelet recovery was significantly faster reaching platelets >20,000/µl after 32 days in cohort I, 25 days in cohort II and 18 days in cohort III. Regimen related toxicity (especially stomatitis) was less in blood stem cell transplant recipients. The 180-day survival was significantly higher in the allogeneic PBSC transplant group (cohort III) with 68%, as compared with 53% in cohort I and 32% in cohort II. Surprisingly, the development of grades II-IV acute GVHD was with 50%, 63%, and 42%, respectively, not statistically different [42].

As reported by the Seattle group [43] using a historical control matched-pair analysis, the recipients of PBSC allografts had significantly faster ANC and platelet recovery and required fewer platelet transfusions than control BM transplant patients. Acute and chronic GVHD (cGVHD), nonleukemic death, leukemic relapse, and survival appeared similar in the two groups. Similar results have now been published by Canadian investigators. When a group of twenty-six allogeneic PBSC transplants was compared with a historical control group of twenty-six BM transplantation patients matched for age and disease status, faster engraftment and platelet recovery were associated with comparable rates of acute (grade II-IV) and cGVHD [44]. It should be emphasized, however, that in view of the relatively small number of patients and, in particular, short follow-up in the series reported so far, the issue of the incidence of cGVHD after allogeneic PBSC transplantation remains an open one. We have observed a significantly higher rate of cGVHD following allografting with PBSCs than with BM [45], although at our most recent data analysis this did not translate into a higher mortality rate because of a lower incidence of relapse.

Ottinger et al. [46] most recently reported an improved immune reconstitution after allogeneic PBSC transplantation as compared with BM allotransplantation. Naive (CD4⁺ CD45RA⁺) and memory (CD4⁺ CD45RO⁺) helper T cells were found to be significantly elevated in patients receiving an allogeneic PBSC transplant, and proliferative responses to phytohemagglutinin, pokeweed mitogen, tetanus toxoid, and candida were found to be more pronounced as well.

Based on the reconstitution data after allogeneic PBSC transplantation reported so far, the question arises whether rHuG-CSF support after transplantation is needed at all to accelerate cell recovery.

	Adverse Effects and Safety of Cytokine Treatment in Normal Donors

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
In a prospective clinical and laboratory study, we evaluated 40 normal PBSC donors who underwent rHuG-CSF treatment (12 µg/kg/day) for stem cell apheresis. Sixty-two percent of donors required oral analgesics during rHuG-CSF treatment. Bone pain (82%), headache (70%), fatigue (20%), and nausea (10%) were reported. Adverse events and laboratory effects (rise in WBC count, alkaline phosphatase, lactate dehydrogenase and minor changes in serum potassium and magnesium) resolved within seven days after apheresis. No apheresis stem cell donor required transfusion or hospitalization, and only one donor required an additional clinic visit after completion of apheresis. By comparison, a retrospective analysis of 33 normal BM donors demonstrated that all received transfusion, three were hospitalized, and three required additional clinic visits after the marrow harvest [22]. Comparable data have now been reported by several other investigators, and available information on the short-term safety profile of rHuG-CSF in normal apheresis donors has recently been reviewed [47].

	Delayed Effects of rHuG-CSF Treatment in Normal Donors

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Little is known about delayed effects of rHuG-CSF treatment and apheresis on a normal hematopoietic system, and, with the exception of sporadic case reports [48], there are no adequate long-term data that address safety issues. We followed 10 normal donors who underwent a three- or four-day rHuG-CSF treatment (12 µg/kg/d) followed by single or tandem apheresis. The PB progenitor cell concentration (CD34⁺ and CD34⁺Thy-1^dim) peak prior to apheresis was followed by a nadir by day 7 and normalized by day 30, with the exception of the most primitive CD34⁺Thy-1^dim CD38^– progenitor subset that reached nadir at day 30. Lymphoid subsets such as CD3, CD4, CD8, suppressor cells (CD3⁺ CD4^–CD8^– TCR_ß⁺), and B cells (CD19⁺) showed a similar pattern with a nadir concentration by day 7, followed, except for B cells, by a rebound by day 30 and slightly subnormal counts at day 100 [49].

Similar data were reported by Martinez et al. [50]. A moderate lymphocytopenia was observed which tends to resolve within three months following cytokine treatment and apheresis. Transient, asymptomatic granulocytopenia following rHuG-CSF mobilization and stem cell apheresis has also been described [51]. Whether this is related to the collection of large numbers of "mobilized" CD34⁺ progenitor cells by leukapheresis remains to be determined.

From the data reported so far, one can assume that the circulating progenitor cell pool has regained a stable, steady-state condition at around 30 to 100 days post blood stem cell collection. Second stem cell collections in normal apheresis donors have been performed (even as early as one to two months after the first), and seem to provide comparable yields of CD34⁺ progenitor cells [52]. Long-term follow-up of PBSC donors exposed to cytokine treatment is necessary to rule out any adverse effects due to genetic predisposition to the related recipient's disease, and/or any adverse effects directly related to cytokine exposure of a normal hematopoietic system. The data available on the long-term effects of rHuG-CSF in patients with severe congenital neutropenia and aplastic anemia do not answer these questions, as these diseases have been shown to carry a predisposition to the development of acute leukemia regardless of rHuG-CSF therapy [53, 54]. It has been estimated, however, that to detect a 10-fold increase in the leukemia risk, more than 2,000 normal donors would need to be followed for up to 10 years or longer, and the detection of a smaller risk increase would require the follow-up of a comparably larger donor pool [55].

	Conclusions

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
Cytokine and, in particular, rHuG-CSF treatment of patients and normal donors for procurement of blood stem cells and for accelerating cell recovery after myeloablative therapy and stem cell transplantation are accepted clinical routine procedures. The potential peripheralization of clonogenic tumor cells by treating the patient with cytokines, and the risk of collecting tumor cell-contaminated autografts is widely addressed in the literature, although controversial. In the allograft situation, short-term rHuG-CSF safety needs to be monitored in normal donors, although preliminary data suggest an acceptable toxicity profile. Moreover, a potential long-term risk of adverse effects in normal donors needs to be carefully addressed by individual institutions as well as national and international registries.

	Future Aspects

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 
As mentioned above, new cytokine/chemokine combinations are expected to improve stem cell and progenitor cell peripheralization by decreasing adverse effects. Such in vivo expansion of the circulating progenitor cell pool could be further improved by a subsequent ex vivo expansion of the apheresis product using a cytokine/chemokine panel. But it is still unclear in the clinical situation whether early stem cells are ex vivo expandable at all.

The cytokine mobilized apheresis product is, due to its cell uniformity, much easier to manipulate. Therefore, allo- and autograft manipulation is expected to shift from negative purging procedures towards positive enrichment and purification of CD34⁺ cells and early subsets. Gene transduction into an in vivo mobilized and ex vivo purified stem cell population with indefinite self-renewal capacity is an attractive treatment option which is already pursued in several clinical trials using, for example, the MDR-1 chemoprotection gene [56].

	References

Top Abstract Introduction Blood Stem Cell Collection... Cell Mobilization in Normal... Stem Cell Mobilization in... Mobilized Blood-Derived Stem... Stem Cell Mobilization Using... Matrix Molecule Interactions and... Factors Affecting Mobilization... Engraftment Characteristics... Adverse Effects and Safety... Delayed Effects of rHuG-CSF... Conclusions Future Aspects References

 

1. Lu L, Walker D, Broxmeyer HE et al. Characterization of adult human marrow hematopoietic progenitors highly enriched by two-color cell sorting with My 10 and major histocompatibility class II monoclonal antibodies. J Immunol 1987;139:1823-1829.[Abstract]

2. Terstappen LWMM, Huang S, Safford M et al. Sequential generations of hematopoietic colonies derived from single nonlineage-committed CD34⁺ CD38^– progenitor cells. Blood 1991;77:1218-1227.[Abstract/Free Full Text]

3. Mayani H, Lansdorp PM. Thy-1 expression is linked to functional properties of primitive hematopoietic progenitor cells from human umbilical cord blood. Blood 1994;83:2410-2417.[Abstract/Free Full Text]

4. Fliedner TM, Steinbach KH. Repopulating potential of hematopoietic precursor cells. Blood Cells 1988;14:393-410.[Medline]

5. Körbling M, Huh YO, Durett A et al. Allogeneic blood stem cell transplantation: peripheralization and yield of donor-derived primitive hematopoietic progenitor cells (CD34⁺ Thy-1^dim) and lymphoid subsets, and possible predictors of engraftment and GVHD. Blood 1995;86:2842-2848.[Abstract/Free Full Text]

6. Link H, Arseniev L, Bähre O et al. Combined transplantation of allogeneic bone marrow and CD34⁺ blood cells. Blood 1995;86:2500-2508.[Abstract/Free Full Text]

7. To LB, Shepperd KM, Haylock DN et al. Single high doses of cyclophosphamide enable the collection of high numbers of hemopoietic stem cells from the peripheral blood. Exp Hematol 1990;18:442-447.[Medline]

8. Körbling M, Przepiorka D, Gajewski J et al. With first successful allogeneic transplantation of apheresis-derived hematopoietic progenitor cells reported, can the recruitment of volunteer matched, unrelated stem cell donors be expanded substantially? Blood 1995;86:1235.[Free Full Text]

9. Peters WP, Rosner G, Ross M et al. Comparative effects of granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) on priming peripheral blood progenitor cells for use with autologous bone marrow after high-dose chemotherapy. Blood 1993;81:1709-1719.[Abstract/Free Full Text]

10. Lane TA, Law P, Maruyama M et al. Harvesting and enrichment of hematopoietic progenitor cells mobilized into the peripheral blood of normal donors by granulocyte-macrophage colony-stimulating factor or G-CSF: potential role in allogeneic marrow transplantation. Blood 1995;85:275-282.[Abstract/Free Full Text]

11. Weaver CH, Longin K, Buckner CD et al. Lymphocyte content in peripheral blood mononuclear cells collected after administration of recombinant human granulocyte colony-stimulating factor. Bone Marrow Transplant 1994;13:411-415.[Medline]

12. Prosper F, Stroncek D, Verfaillie CM. Mobilization of LTC-IC in normal donors treated with G-CSF: phenotypic analysis of mobilized PBPC. Blood 1995;86:464a.

13. O'Gorman MRG, Martin JS, Jacobs P et al. Serial flow cytometric evaluation of CD34⁺ subsets in growth factor mobilized peripheral blood aphereses. Bone Marrow Transplantation (in press).

14. Tjønnfjord GE, Steen R, Evensen SA et al. Characterization of CD34⁺ peripheral blood cells from healthy adults mobilized by recombinant human granulocyte colony-stimulating factor. Blood 1994;84:2795-2801.[Abstract/Free Full Text]

15. Stroncek D, Clay M, Jaszcz W et al. Longer than 5 days of G-CSF mobilization of normal individuals results in lower CD34⁺ cell counts. Blood 1994;84:541a.

16. Anderlini P, Przepiorka D, Huh Y et al. Duration of filgrastim mobilization and apheresis yield of CD34⁺ progenitor cells and lymphoid subsets in normal donors for allogeneic transplantation. Br J Haematol 1996;93:940-942.[Medline]

17. Höglund M, Smedmyr B, Simonsson B et al. Dose-dependent mobilisation of haematopoietic progenitor cells in healthy volunteers receiving glycosylated rHuG-CSF. Bone Marrow Transplant 1996;18:19-27.[Medline]

18. Wailer CF, Bertz H, Wenger MK et al. Mobilization of peripheral blood progenitor cells for allogeneic transplantation: efficacy and toxicity of a high-dose rhG-CSF regimen. Bone Marrow Transplant 1996;18:279-283.[Medline]

19. Höglund M, Bengtsson M, Cour-Chabernaud V et al. Glycosylated rHuG-CSF is more potent than non-glycosylated rHuG-CSF in mobilisation of peripheral blood progenitor cells (PBPC) in healthy volunteers. Blood 1995;86:464a.

20. Kanold J, Rapatel C, Berger M et al. Use of G-CSF alone to mobilize peripheral blood stem cells for collection from children. Br J Haematol 1994;88:633-635.[Medline]

21. Takaue Y, Kawano Y, Abe T et al. Collection and transplantation of peripheral blood stem cells in very small children weighing 20 kg or less. Blood 1995;86:372-380.[Abstract/Free Full Text]

22. Anderlini P, Przepiorka D, Seong D et al. Clinical toxicity and laboratory effects of granulocyte-colony-stimulating factor (filgrastim) mobilization and blood stem cell apheresis from normal donors, and analysis of charges for the procedures. Transfusion 1996;36:590-595.[Medline]

23. Körbling M, Chan KW, Anderlini P et al. Allogeneic peripheral blood stem cell transplantation using normal patient related pediatric donors. Bone Marrow Transplant 1996;18:885-890.[Medline]

24. Moore MAS. Expansion of myeloid stem cells in culture. Semin Hematol 1995;32:183-200.[Medline]

25. Pettengell R, Luft T, Henschler R et al. Direct comparison by limiting dilution analysis of long-term culture-initiating cells in human bone marrow, umbilical cord blood, and blood stem cells. Blood 1994;84:3653-3659.[Abstract/Free Full Text]

26. Kaushansky K. Thrombopoietin: the primary regulator of platelet production. Blood 1995;86:419-431.[Free Full Text]

27. Molineux G, Hartley C, McElroy P et al. Megakaryocyte growth and development factor accelerates platelet recovery in peripheral blood progenitor cell transplant recipients. Blood 1996;88:366-376.[Abstract/Free Full Text]

28. Geissler K, Peschel C, Niederwieser D et al. Potentiation of granulocyte colony-stimulating factor-induced mobilization of circulating progenitor cells by seven-day pretreatment with Interleukin-3. Blood 1996;87:2732-2739.[Abstract/Free Full Text]

29. Huhn RD, Yurkow EJ, Tushinski R et al. Recombinant human interleukin-3 (rhIL-3) enhances the mobilization of peripheral blood progenitor cells by recombinant human granulocyte colony-stimulating factor (rhG-CSF) in normal volunteers. Exp Hematol 1996;24:839-847.[Medline]

30. Geissler K, Valent P, Mayer P et al. Recombinant human interleukin-3 expands the pool of circulating hematopoietic progenitor cells in primates—synergism with recombinant human granulocyte/macrophage colony-stimulating factor. Blood 1990;75:2305-2310.[Abstract/Free Full Text]

31. Hunter MG, Bawden L, Brotherton D et al. BB-10010: an active variant of human macrophage inflammatory protein-1 with improved pharmaceutical properties. Blood 1995;86:4400-4408.[Abstract/Free Full Text]

32. Lord BI, Woolford LB, Wood LM et al. Mobilization of early hematopoietic progenitor cells with BB-10010: a genetically engineered variant of human macrophage inflammatory protein-1 alpha. Blood 1995;85:3412-3415.[Abstract/Free Full Text]

33. Broxmeyer HE, Hague NL, Sledge GW et al. Suppression of marrow and mobilization of blood myeloid progenitors in vivo by BB10010, a genetically engineered variant of human macrophage inflammatory protein (MIP-1), in a phase I clinical trial in patients with relapsed/refractory breast cancer. Blood 1995;86(suppl 1):12a.

34. Levesque JP, Leavesley DI, Niutta S et al. Cytokines increase human hemopoietic cell adhesiveness by activation of very late antigen (VLA)-4 and VLA-5 integrins. J Exp Med 1995;181:1805-1815.[Abstract/Free Full Text]

35. McNiece IK, Langley KE, Zsebo KM. Recombinant human stem cell factor synergizes with GM-CSF, G-CSF, IL-3 and EPO to stimulate human progenitor cells of the myeloid and erythroid lineages. Exp Hematol 1991;19:226-231.[Medline]

36. Andrews RG, Briddell RA, Knitter GH et al. Rapid engraftment by peripheral blood progenitor cells mobilized by recombinant human stem cell factor and recombinant human granulocyte colony-stimulating factor in nonhuman primates. Blood 1995;85:15-20.[Abstract/Free Full Text]

37. McNiece I, Glaspy J, LeMaistre F et al. Effects of recombinant methionyl human stem cell factor (rhSCF) and filgrastim (rhG-CSF) on mobilization of peripheral blood progenitor cells: preliminary laboratory results from a phase I/II study. Blood 1993;82(suppl 1):84a.

38. Verfaillie C, Hurley R, Bhatia R et al. Role of bone marrow matrix in normal and abnormal hematopoiesis. Crit Rev Oncol Hematol 1994;16:201-224.[Medline]

39. Simmons PJ, Masinovsky B, Longenecker BM et al. Vascular cell adhesion molecule-1 expressed by bone marrow stromal cells mediates the binding of hematopoietic progenitor cells. Blood 1992;80:388-395.[Abstract/Free Full Text]

40. Papayannopoulou T, Nakamoto B. Peripheralization of hematopoietic progenitors in primates treated with anti-VLA₄ integrin. Proc Natl Acad Sci USA 1993;90:9374-9378.[Abstract/Free Full Text]

41. Anderlini P, Przepiorka D, Seong D et al. Factors affecting mobilization of CD34⁺ cells in normal donors treated with filgrastim. Transfusion (in press).

42. Przepiorka D, Anderlini P, Ippoliti C et al. Allogeneic blood stem cell transplantation: reduction in early treatment-related morbidity and mortality for patients with advanced hematologic malignancies.Bone Marrow Transplant (in press).

43. Bjerke J, Bensinger W, Anasetti C et al. Circulating hematopoietic progenitor cell transplantation from unrelated donors: is this the future? Progressi in Ematologia Clinica 1996;15:135-141.

44. Russel JA, Brown C, Brown T et al. Allogeneic blood cell transplants for haematological malignancy: preliminary comparison of outcomes with bone marrow transplantation. Bone Marrow Transplant 1996;17:703-708.[Medline]

45. Anderlini P, Przepiorka D, Khouri I et al. Chronic graft-versus-host disease after allogeneic marrow or blood stem cell transplantation. Blood 1995;86:109a.

46. Ottinger HD, Beelen DW, Scheulen B et al. Improved immune reconstitution after allotransplantation of peripheral blood stem cells instead of bone marrow. Blood 1996;88:2775-2779.[Abstract/Free Full Text]

47. Anderlini P, Przepiorka D, Champlin R et al. Biologic and clinical effects of granulocyte colony-stimulating factor in normal individuals. Blood 1996;88:2819-2825.[Free Full Text]

48. Sakamaki S, Matsunaga T, Hirayama Y et al. Haematological study of healthy volunteers 5 years after G-CSF. Lancet 1995;346:1432-1433.[Medline]

49. Körbling M, Anderlini P, Durett A et al. Delayed effects of rhG-CSF mobilization treatment and apheresis on circulating CD34⁺ and CD34⁺Thy-1^dim CD38^– progenitor cells, and lymphoid subsets in normal stem cell donors for allogeneic transplantation. Bone Marrow Transplant (in press).

50. Martinez C, Urbano-Ispizua A, Rozman C et al. Effects of G-CSF administration and peripheral blood progenitor cell collection in 20 healthy donors. Ann Hematol 1996;72:269-272.[Medline]

51. Anderlini P, Przepiorka D, Seong D et al. Transient neutropenia in normal donors after G-CSF mobilization and stem cell apheresis. Br J Haematol 1996;94:155-158.[Medline]

52. Anderlini P, Lauppe J, Przepiorka D et al. Peripheral blood stem cell apheresis in normal donors: feasibility and yield of second collections. Br J Haematol (in press).

53. Gilman P, Jackson D, Guild H. Congenital agranulocytosis: prolonged survival and terminal acute leukemia. Blood 1970;36:576-585.[Abstract/Free Full Text]

54. de Planque MM, Bacigalupo A, Würsch A et al. Long-term follow-up of severe aplastic anemia patients treated with antithymocyte globulin. Br J Haematol 1989;73:121-126.[Medline]

55. Hasenclever D, Sextro M. Safety of alloPBPCT donors: biometrical considerations on monitoring long term risks. Bone Marrow Transplant 1996;17(suppl 2):S28-S30.

56. Kavanagh J, Hanania EG, Giles RE et al. Genetic modification of cells used for transplant following intensive therapy for ovarian cancer and breast cancer. Blood 1996;88:272a.

This article has been cited by other articles:

				P. Schwarzenberger, W. Huang, P. Oliver, P. Byrne, V. La Russa, Z. Zhang, and J. K. Kolls IL-17 Mobilizes Peripheral Blood Stem Cells with Short- and Long-Term Repopulating Ability in Mice J. Immunol., August 15, 2001; 167(4): 2081 - 2086. [Abstract] [Full Text] [PDF]

				N. A. Marshall, J. G. Howe, R. Formica, D. Krause, J. E. Wagner, N. Berliner, J. Crouch, I. Pilip, D. Cooper, B. R. Blazar, et al. Rapid reconstitution of Epstein-Barr virus-specific T lymphocytes following allogeneic stem cell transplantation Blood, October 15, 2000; 96(8): 2814 - 2821. [Abstract] [Full Text] [PDF]

				F. Arpaci, S. Komurcu, B. Ozturk, A. Ozet, C. Kinalp, A. Sengul, M. Beyzadeoglu, Y. Pak, and A. Yalcin A Successful and Simplified Filgrastim Primed Single Apheresis Method Without Large Volume Apheresis for Peripheral Blood Stem Cell Collection Jpn. J. Clin. Oncol., March 1, 2000; 30(3): 153 - 158. [Abstract] [Full Text] [PDF]

				M. Engelhardt, H. Bertz, M. Afting, C. F. Waller, and J. Finke High- Versus Standard-Dose Filgrastim (rhG-CSF) for Mobilization of Peripheral-Blood Progenitor Cells From Allogeneic Donors and CD34+ Immunoselection J. Clin. Oncol., July 1, 1999; 17(7): 2160 - 2160. [Abstract] [Full Text] [PDF]