Reduced dose of lenograstim is as efficacious as standard dose of filgrastim for peripheral blood stem cell mobilization and transplantation: a randomized study in patients undergoing autologous peripheral stem cell transplantation

New insight into strategies used to develop long-acting G-CSF biologics for neutropenia therapy

Over the last 20 years, granulocyte colony-stimulating factors (G-CSFs) have become the major therapeutic option for the treatment of patients with neutropenia. Most of the current G-CSFs require daily injections, which are inconvenient and expensive for patients. Increased understanding of G-CSFs' structure, expression, and mechanism of clearance has been very instrumental in the development of new generations of long-acting G-CSFs with improved efficacy. Several approaches to reducing G-CSF clearance via conjugation techniques have been investigated. PEGylation, glycosylation, polysialylation, or conjugation with immunoglobulins or albumins have successfully increased G-CSFs' half-lives. Pegfilgrastim (Neulasta) has been successfully approved and marketed for the treatment of patients with neutropenia. The rapidly expanding market for G-CSFs has increased demand for G-CSF biosimilars. Therefore, the importance of this review is to highlight the principle, elimination's route, half-life, clearance, safety, benefits, and limitations of different strategies and techniques used to increase the half-life of biotherapeutic G-CSFs. Understanding these strategies will allow for a new treatment with more competitive manufacturing and lower unit costs compared with that of Neulasta.

Efficacy of hematopoietic stem cell mobilization regimens in patients with hematological malignancies: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

Efficient mobilization of hematopoietic stem cells (HSCs) from bone marrow niche into circulation is the key to successful collection and transplantation in patients with hematological malignancies. The efficacy of various HSCs mobilization regimens has been widely investigated, but the results are inconsistent.

METHODS

We performed comprehensive databases searching for eligible randomized controlled trials (RCTs) that comparing the efficacy of HSCs mobilization regimens in patients with hematological malignancies. Bayesian network meta-analyses were performed with WinBUGS. Standard dose of granulocyte colony-stimulating factor (G-CSF SD) was chosen as the common comparator. Estimates of relative treatment effects for other regimens were reported as mean differences (MD) or odds ratio (OR) with associated 95% credibility interval (95% CrI). The surface under the cumulative ranking curve (SUCRA) were obtained to present rank probabilities of all included regimens.

RESULTS

Databases searching and study selection identified 44 eligible RCTs, of which the mobilization results are summarized. Then we compared the efficacy of mobilization regimens separately for patients with multiple myeloma (MM) and non-Hodgkin lymphoma (NHL) by including 13 eligible trials for network meta-analysis, involving 638 patients with MM and 592 patients with NHL. For patients with MM, data are pooled from 8 trials for 6 regimens, including G-CSF in standard dose (SD) or reduced dose (RD) combined with cyclophosphamide (CY), intermediate-dose cytarabine (ID-AraC) or plerixafor. The results show that compared with G-CSF SD alone, 3 regimens including ID-AraC + G-CSF SD (MD 14.29, 95% CrI 9.99-18.53; SUCRA 1.00), G-CSF SD + Plerixafor SD (MD 4.15, 95% CrI 2.92-5.39; SUCRA 0.80), and CY + G-CSF RD (MD 1.18, 95% CrI 0.29-2.07; SUCRA 0.60) are associated with significantly increased total number of collected CD34+ cells (× 106/kg), among which ID-AraC + G-CSF SD ranked first with a probability of being best regimen of 100%. Moreover, ID-AraC + G-CSF SD and G-CSF SD + Plerixafor SD are associated with significantly higher successful rate of achieving optimal target (collecting ≥ 4-6 × 106 CD34+ cells/kg). For patients with NHL, data are pooled from 5 trials for 4 regimens, the results show that compared with G-CSF SD alone, G-CSF SD + Plerixafor SD (MD 3.62, 95% CrI 2.86-4.38; SUCRA 0.81) and G-CSF SD plus the new CXC chemokine receptor-4 (CXCR-4) antagonist YF-H-2015005 (MD 3.43, 95% CrI 2.51-4.35; SUCRA 0.69) are associated with significantly higher number of total CD34+ cells collected. These 2 regimens are also associated with significantly higher successful rate of achieving optimal target. There are no significant differences in rate of achieving optimal target between G-CSF SD + Plerixafor SD and G-CSF + YF-H-2015005.

CONCLUSIONS

In conclusion, ID-AraC plus G-CSF is associated with the highest probability of being best mobilization regimen in patients with MM. For patients with NHL, G-CSF in combination with plerixafor or YF-H-2015005 showed similar improvements in HSCs mobilization efficacy. The relative effects of other chemotherapy-based mobilization regimens still require to be determined with further investigations.

Advances in the pharmacological management of neutropenia in solid tumors: the advent of biosimilars

Introduction: Severe neutropenia and infections are potentially life-threatening complications of cytotoxic antineoplastic therapies and often require hospitalization with a severe economic impact. Furthermore, hematological toxicity frequently results in chemotherapy dose reductions and delays that could interfere with disease control.Areas covered: This review provides an overview of granulocyte colony-stimulating factors (G-CSFs) including pegylated molecules, as well as more recent biosimilar G-CSFs, focusing on the toxicity, pharmacokinetics, and efficacy of these compounds.Expert opinion: The administration of hematopoietic growth factors in primary and secondary prophylaxis of neutropenia is a standard supportive care measure. Recently, several biosimilars have been developed. The market for biosimilar agents seems to be increasing over time thanks to their similar effectiveness and safety, compared with their originators, but lower costs.

Construction of a Pichia pastoris strain efficiently producing recombinant human granulocyte-colony stimulating factor (rhG-CSF) and study of its biological activity on bone marrow cells

Non-glycosylated, recombinant human granulocyte colony-stimulating factor (rhG-CSF), produced by Escherichia coli (filgrastim, leukostim) is widely used to treat a number of serious human diseases and aids in the recovery post bone marrow transplantation. Although glycosylation is not required for the manifestation of the biological activity of G-CSF, a number of studies have shown that the carbohydrate residue significantly increases the physicochemical stability of the G-CSF molecule. Therefore, the aim of the present study was to design a Pichia pastoris strain capable of producing glycosylated rhG-CSF, and to study its effects on rat bone marrow cells. The nucleotide sequence of the rhG-CSF gene has been optimized for expression in P. pastoris, synthesized, cloned into the pPICZαA vector and expressed under the control of the AOX promoter in P. pastoris X33. One of the selected clones secreting rhG-CSF, produced 100-120 mg/l of rhG-CSF three days post-induction with methanol. The recombinant cytokine was purified using two-step, ion-exchange chromatography. The final yield of purified G-CSF was 35 mg/L of culture medium. The biological activity of rhG-CSF was examined in rat bone marrow cells. The P. pastoris strain was designed to produce relatively high levels of rhG-CSF. The rhG-CSF protein had a strong stimulating effect on the growth of rat bone marrow cells, which was comparable to that of the commercial drug leukostim, but showed a more persistent effect on granulocyte cells and monocyte sprouts, enabling the enhanced maintenance of the viability of the cells into the 4th day of incubation.

Lenograstim and filgrastim in the febrile neutropenia prophylaxis of hospitalized patients: efficacy and cost of the prophylaxis in a retrospective survey

Purpose

We conducted a retrospective study to evaluate the efficacy and related costs of using two different molecules of granulocyte-colony stimulating factor (G-CSF) (lenograstim - LENO or filgrastim - FIL) as primary prophylaxis of chemotherapy-induced neutropenia in a hematological inpatient setting.

Methods

The primary endpoints of the analysis were the efficacy of the two G-CSFs in terms of the level of white blood cells, hemoglobin and platelets at the end of the treatment and the per capita direct medical costs related to G-CSF prophylaxis.

Results

Two hundred twelve patients (96 LENO, 116 FIL) have been evaluated. The following statistically significant differences have been observed between FIL and LENO: the use of a higher number of vials (11 vs 7; P<0.03) to fully recover bone marrow, a higher grade 3-4 neutropenia at the time of G-CSF discontinuation (29.3% vs 16.7%; P=0.031) and an increased number of days of hospitalization (8 vs 5; P<0.005). A longer hospital stay before discharge was necessary (12 vs 10), which reflects the higher final costs per patient (median treatment cost per cycle 10.706 € for LENO, compared to 12.623 € for FIL).

Conclusion

The use of LENO has been associated with a lower number of days of hospitalization, number of vials and less incidence of grade 3-4 neutropenia at the time of G-CSF discontinuation. LENO seems to be cost-saving when compared with FIL (-15.2%).

Lenograstim 5 µg/kg is not superior to biosimilar filgrastim 10 µg/kg in lymphoma patients undergoing peripheral blood stem cell mobilization after chemotherapy: preliminary results from a prospective randomized study

BACKGROUND

Randomized trials comparing chemomobilization efficiency between lenograstim and biosimilar filgrastim are lacking. Our previous retrospective study suggested that lenograstim could be more effective than biosimilar filgrastim when used at the same conventional dosage (5 µg/kg) only in lymphoma patients undergoing peripheral blood stem cell mobilization. We planned a prospective randomized study comparing lenograstim 5 µg/kg with biosimilar filgrastim 10 µg/kg to verify the hypothesis of lenograstim superiority even at half the dosage (stress test). Herein we report data after enrolling 60% of planned patients.

STUDY DESIGN AND METHODS

From October 2014 to November 2017, a total of 42 of 70 planned patients with lymphoma were randomly assigned to receive lenograstim 5 µg/kg (21) or biosimilar filgrastim 10 µg/kg (21). Patients were stratified according to treatment line at the time of mobilization (1 or ≥2). Primary endpoint was the rate of achievement of the CD34+ cell collection target dose (≥ 4 × 10⁶ /kg). An improvement by 23% was expected to validate the hypothesis of lenograstim superiority.

RESULTS

The two cohorts were balanced for all the baseline features. We observed an identical rate of patients able to reach the targeted CD34+ cell dose and of mobilization failures (90.4 and 4.8% in both cohorts) and a perfect equivalence in any of the secondary collection outcomes. The hypothesis of lenograstim superiority was not corroborated at interim analysis.

CONCLUSION

Lenograstim at conventional dosage has failed to demonstrate its superiority over biosimilar filgrastim at double the dosage at interim analysis in their first head-to-head trial.

Granulocyte colony-stimulating factor for the treatment of cardiovascular diseases: An update with a critical appraisal

Heart failure and acute myocardial infarction are conditions that are associated with high morbidity and mortality. Significant dysfunction of the heart muscle can occur as the consequence of end-stage chronic cardiovascular diseases or acute ischemic events that are marked by large infarction area and significant tissue necrosis. Despite the remarkable improvement of conventional treatments, a substantial proportion of patients still develops severe heart failure that can only be resolved by heart transplantation or mechanical device implantation. Therefore, novel approaches based on stem-cell therapy can directly modify the disease process and alter its prognosis. The ability of the stem-cells to modify and repair the injured myocardium is a challenging but intriguing concept that can potentially replace expensive and invasive methods of treatment that are associated with increased risks and significant financial costs. In that sense, granulocyte colony-stimulating factor (G-CSF) seems as an attractive treatment approach. Based on the series of pre-clinical experiments and a limited amount of clinical data, it was demonstrated that G-CSF agents possess the ability to mobilize stem-cells from bone marrow and induce their differentiation into cardiomyocytes or endothelial cells when brought into contact with injured regions of the myocardium. However, clinical benefits of G-CSF use in damaged myocardium remain unclear and are the topic of expert discussion. The main goal of this review is to present relevant and up-to-date evidence on G-CSF therapy use in pre-clinical models and in humans and to provide a rationale for its potential clinical applications in the future.

Autologous Stem Cell Mobilization and Collection

Peripheral blood stem cell collection is an effective approach to obtain a hematopoietic graft for stem cell transplantation. Developing hematopoietic stem/progenitor cell (HSPC) mobilization methods and collection algorithms have improved efficiency, clinical outcomes, and cost effectiveness. Differences in mobilization mechanisms may change the HSPC content harvested and result in different engraftment kinetics and complications. Patient-specific factors can affect mobilization. Incorporating these factors in collection algorithms and improving assays for evaluating mobilization further extend the ability to obtain sufficient HSPCs for hematopoietic repopulation. Technological advance and innovations in leukapheresis have improved collection efficiency and reduced adverse effects.

Use of biosimilar filgrastim compared with lenograstim in autologous haematopoietic stem-cell transplant and in sibling allogeneic transplant

OBJECTIVES

Biosimilar filgrastim was compared with lenograstim for autologous haematopoietic stem-cell transplant (HSCT) in patients with haematological malignancies. Data from a separate group of sibling donors who underwent allogeneic HSCT are also reported.

METHODS

Patients with lymphoma or multiple myeloma (MM) who underwent autologous HSCT with biosimilar filgrastim were compared with a historical control group of patients who received lenograstim. Peripheral blood (PB) cells counts were monitored after 7-8 consecutive days of granulocyte-colony stimulating factor (G-CSF) injection and apheresis was performed on day 8 if PB CD34+ cell count was ⩾10 cells/µl. The target PB CD34+ cell doses were ⩾2.0 × 10(6)/kg (lymphoma), ⩾4.0 × 10(6)/kg (MM ⩾60 years old) or ⩾8.0 × 10(6)/kg (MM <60 years old).

RESULTS

A total of 259 patients were included in the autologous HSCT comparison (biosimilar filgrastim, n = 104; lenograstim, n = 155). In patients with lymphoma and older MM patients (⩾60 years old), no significant differences were observed between groups with regard to stem-cell mobilization parameters. However, in MM patients <60 years old, all parameters were significantly superior in the biosimilar filgrastim group, including the need for 1 rather than 2 apheresis procedures. No significant differences were observed between groups in median number of days to absolute neutrophil count (ANC) or platelet recovery. In the allogeneic setting, 47 sibling donors received biosimilar filgrastim. Mean CD34+ count at the first apheresis was 6.1 × 10(6)/kg. A total of 13 donors needed a second apheresis and 4 required a third. Among recipients, median days to ANC recovery was 16 (10-28) and to platelet recovery was 13 (9-54).

CONCLUSIONS

Biosimilar filgrastim is as effective as lenograstim for autologous HSCT in patients with lymphoma or MM patients ⩾60 years old. However, mobilization with biosimilar filgrastim appeared to be superior to that with lenograstim in younger MM patients.

The current status in hematopoietic stem cell mobilization

Hemotopoietic stem cell mobilization with cytokines alone, has still been widely accepted as the initial attempt for stem cell mobilization. Chemotherapy based mobilization can be preferred as first choice in high risk patients or for remobilization. But mobilization failure still remains to be a problem in one third of patients. Salvage mobilization strategies have been composed to give one more chance to 'poor mobilizers'. Synergistic effect of a reversible inhibitor of CXCR4, plerixafor, with G-CSF has opened a new era for these patients. Preemptive approach in predicted poor mobilizers, immediate salvage approach for patients with suboptimal mobilization or remobilization approach of plerixafor in failed mobilizers have all been demonstrated convincing results in various studies. Alternative CXCR4 inhibitors, VLA4 inhibitors, bortezomib, parathormone have also been emerged as novel agents for mobilization failure.

Filgrastim, lenograstim and pegfilgrastim in the mobilization of peripheral blood progenitor cells in patients with lymphoproliferative malignancies

Patients with lymphoproliferative disorders, candidate to autologous stem cell transplantation (ASCT), require mobilization with chemotherapy and granulocyte colony -stimulating factor (G-CSF). This study looked for differences in hematopoietic peripheral stem cells (HPSCs) mobilization in response to the three available G-CSFs, namely lenograstim, filgrastim, and pegfilgrastim. Between 2000 and 2012, 146 patients (66 M and 80 F) who underwent ASCT for multiple myeloma, non-Hodgkin's lymphoma or Hodgkin's lymphoma were studied. All patients received induction therapy and then a mobilization regimen with cyclophosphamide plus lenograstim, or filgrastim, or pegfilgrastim. From days 12 to 14, HPSCs were collected by two to three daily leukaphereses. Our results show that high-dose cyclophosphamide plus lenograstim achieved adequate mobilization and the collection target more quickly and with fewer leukaphereses as compared to filgrastim and pegfilgrastim. No differences between the three regimens were observed regarding toxicity and days to WBC and platelet recovery. Thus, lenograstim may represent the ideal G-CSF for PBSC mobilization in patients with lymphoproliferative diseases. Further studies are needed to confirm these results and better understand the biological bases of these differences.

Peripheral blood stem cell mobilization and engraftment after autologous stem cell transplantation with biosimilar rhG-CSF

INTRODUCTION

Biosimilar versions of filgrastim [recombinant human granulocyte colony-stimulating factor (rhG-CSF)] are now widely available. To date, biosimilar rhG-CSF has demonstrated a comparable quality, safety and efficacy profile to the originator product (filgrastim [Neupogen(®)], Amgen Inc., CA, USA) in the prevention and management of neutropenia. Biosimilar rhG-CSFs have also been used to induce peripheral blood stem cell (PBSC) mobilization in patients undergoing autologous stem cell transplantation (AHSCT). The authors have examined the effectiveness of a biosimilar rhG-CSF (Zarzio(®), Sandoz Biopharmaceuticals, Holzkirchen, Germany) in two retrospective studies across two medical centers in Hungary.

METHODS

In Study 1, 70 patients with hematological malignancies scheduled to undergo AHSCT received chemotherapy followed by biosimilar rhG-CSF (2 × 5 μg) for facilitating neutrophil, leukocyte, and platelet engraftment. In study 2, 40 additional patients with lymphoid malignancies and planned AHSCT received chemotherapy followed by biosimilar rhG-CSF for PBSC mobilization. The effectiveness of treatment was assessed by the average yield of cluster of differentiation (CD) 34+ cells and the number of leukaphereses required.

RESULTS

In Study 1 (patients undergoing AHSCT), the median age was 56 years and most patients were male (60%). The conditioning regimens were mainly high-dose melphalan (n = 41) and carmustine (BiCNU(®), Bristol-Myers Squibb, NJ, USA), etoposide, cytarabine and melphalan BEAM (n = 21). Median times to absolute neutrophil and leukocyte engraftment were 9 (range 8-11 days) and 10 (8-12) days, respectively. Median time to platelet engraftment was 10.5 days (7-19 days). In Study 2, the patients' median age was 54 years and the majority (57.5%) were female. The median time interval between day 1 of mobilizing chemotherapy and first leukapheresis was 12 (9-27) days. In the autologous PBSC grafts, the median number of CD34+ cells harvested was 5.2 × 10(6)/kg (2.22-57.07 × 10(6)/kg). The median yield of CD34+ cells per leukapheresis product was 2.47 × 10(6)/kg. In total, 58 leukaphereses were performed in 40 successfully harvested patients.

CONCLUSIONS

In line with previous studies with originator rhG-CSF, the findings of this study indicate that biosimilar rhG-CSF following AHSCT is effective and generally well tolerated in the engraftment setting. In addition, biosimilar rhG-CSF is comparable to the originator rhG-CSF in terms of kinetics of PBSC mobilization and yield of CD34+ cells. In conclusion, the authors have demonstrated that the use of biosimilar rhG-CSF is effective and safe in autologous PBSC mobilization and engraftment after AHSCT.

The effect of gradual increment in rhG-CSF dose on stem cell yields in patients with multiple myeloma mobilized with intermediate dose cyclophosphamide plus rhG-CSF

Cyclophosphamide along with recombinant human granulocyte-colony stimulating factor (rhG-CSF) is a commonly used strategy for mobilization. However, the optimal timing for rhG-CSF initiation after cyclophosphamide has not been determined as conclusively as has the G-CSF dose. In this paper, we aimed to present gradual dose increment of rhG-CSF between the third day of mobilization and time to apheresis that is started with 5 μg/kg (from day 3 to day 7) and continued with 10 μg/kg (from day 8 to time to apheresis) for peripheral blood stem cell (PBSC) mobilization in multiple myeloma (MM) patients and its effect on stem cell yield and mobilization success. Data from 30 consecutive patients with MM who underwent PBSC mobilization between October 2011 and June 2013, were retrospectively reviewed. While twenty-eight of 30 patients (93.3%) were successfully mobilized, 2 patients (6.7%) had mobilization failure. The final median CD34+ cell dose harvested from the patients was 9.5×10(6)/kg. The median number of apheresis was 2.5 (range, 0-3). Twenty-four patients (80%) yielded >2×10(6) CD34+ cells/kg in one apheresis procedure. In conclusion, our regimen might be used to decrease the mobilization failure regarding the low dose rhG-CSF use and provide a cost effective strategy.

Comparison of filgrastim and lenograstim in pediatric solid tumors

PURPOSE

Chemotherapy-induced febrile neutropenia (FEN), which causes treatment delays or chemotherapy dose reductions, is a serious side effect of cancer treatment. In Turkey, recombinant G-CSF (rG-CSF) has been used since 2000 to control neutropenia. The purpose of this prospective randomized study is to compare the effectiveness, toxicities and the cost of these two drugs in children.

METHODS

Between April and December 2008, 29 patients were administered 40 courses of chemotherapy in each arm. A randomized crossover study was designed. All patients were administered rG-CSF 24 hours after the last day of chemotherapy as a secondary prophylaxis. Complete blood counts as well as peripheral blood progenitor (CD34+) cell levels were measured before G-CSF treatment and on the fifth and the seventh day of treatment.

RESULTS

The median duration of neutropenia, FEN, the length of hospitalization, the incidence of FEN, and documented infection was not different between the two rG-CSF treatment groups. Erythrocyte and platelet transfusion rates were also similar. After 7 days, the mean leukocyte (WBC [white blood cell]) and neutrophil count (ANC [absolute neutrophil count]), hemoglobin and platelet levels were not significantly different. However, the CD34+ cell level was significantly higher in the lenograstim group. Lenograstim was also more expensive than filgrastim. No serious side effects were reported for either rG-CSF treatment.

CONCLUSIONS

There is no difference following the administration of either lenograstim or filgrastim for the duration of neutropenia, FEN or hospitalization for pediatric cancer patients. For stem cell mobilization, lenograstim was superior to filgrastim.

New G-CSF agonists for neutropenia therapy

INTRODUCTION

Granulocyte colony-stimulating factor (G-CSF; filgrastim) and its pegylated form (pegfilgrastim) are widely used to treat neutropenia associated with myelosuppressive chemotherapy and bone marrow transplantation, AIDS-associated or drug-induced neutropenia, and neutropenic diseases. G-CSF facilitates restoration of neutrophil counts, decreases incidence of infection/febrile neutropenia and reduces resource utilization. G-CSF is also widely used to mobilize peripheral blood stem cells for hematopoietic transplant.

AREAS COVERED

We review the therapeutic use, cost effectiveness and disease impact of G-CSF for neutropenia, development of G-CSF biosimilars and current next-generation discovery efforts.

EXPERT OPINION

G-CSF has impacted the treatment and survival of patients with congenital neutropenias. For chemotherapy-associated neutropenia, cost effectiveness and impact on survival are still unclear. G-CSFs are expensive and require systemic administration. Market entry of new biosimilars, some with enhanced half-life profiles, will probably reduce cost and increase cost effectiveness. There is no evidence that marketed or late development biosimilars display effectiveness superior to current G-CSFs. Second-generation compounds that mimic the activity of G-CSF at its receptor, induce endogenous ligand(s) or offer adjunct activity have been reported and represent attractive G-CSF alternatives, but are in preclinical stages. A significant therapeutic advance will require reduced depth and duration of neutropenia compared to current G-CSFs.

Advances in stem cell mobilization

The use of mobilized peripheral blood stem cells (PBSCs) has largely replaced the use of bone marrow as a source of stem cells for both allogeneic and autologous stem cell transplantation. G-CSF with or without chemotherapy is the most commonly used regimen for stem cell mobilization. Some donors or patients, especially the heavily pretreated patients, fail to mobilize the targeted number of stem cells with this regimen. A better understanding of the mechanisms involved in hematopoietic stem cell (HSC) trafficking could lead to the development of newer mobilizing agents and therapeutic approaches. This review will cover the current methods for stem cell mobilization and recent developments in the understanding of the biology of stem cells and the bone marrow microenvironment.

Current status of stem cell mobilization

New advances in effective mobilization of peripheral blood stem cells have permitted a greater proportion of patients to benefit from autologous stem cell transplantation. In this review, the relative merits of peripheral blood and mobilized bone marrow are discussed. All available agents are reviewed. A critical assessment of the appropriate dosing and frequency of available growth factors is undertaken, and the most commonly used chemotherapy plus growth factor combinations are covered. Specific recommendations for patients who are poor mobilizers are dealt with including the role of plerixafor.

The Mobilization and Effect of Endogenous Bone Marrow Progenitor Cells in Diabetic Wound Healing

Diabetic patients suffer from impaired wound healing, characterized by only modest angiogenesis and cell proliferation. Stem cells may stimulate healing, but little is known about the kinetics of mobilization and function of bone marrow progenitor cells (BM-PCs) during diabetic wound repair. The objective of this study was to investigate the kinetics of BM-PC mobilization and their role during early diabetic wound repair in diabetic db/db mice. After wounding, circulating hematopoietic stem cells (Lin-c-Kit+Sca-1+) stably increased in the periphery and lymphoid tissue of db/db mice compared to unwounded controls. Peripheral endothelial progenitor cells (CD34+VEGFR+) were 2.5- and 3.5-fold increased on days 6 and 10 after wounding, respectively. Targeting the CXCR4—CXCL12 axis induced an increased release and engraftment of endogenous BM-PCs that was paralleled by an increased expression of CXCL12/SDF-1α in the wounds. Increased levels of peripheral and engrafted BM-PCs corresponded to stimulated angiogenesis and cell proliferation, while the addition of an agonist (GM-CSF) or an antagonist (ACK2) did not further modulate wound healing. Macroscopic histological correlations showed that increased levels of stem cells corresponded to higher levels of wound reepithelialization. After wounding, a natural release of endogenous BM-PCs was shown in diabetic mice, but only low levels of these cells homed in the healing tissue. Higher levels of CXCL12/SDF-1α and circulating stem cells were required to enhance their engraftment and biological effects. Despite controversial data about the functional impairment of diabetic BM-PCs, in this model our data showed a residual capacity of these cells to trigger angiogenesis and cell proliferation.

Usage of granulocyte colony-stimulating factor every 2 days is clinically useful and cost-effective for febrile neutropenia during early courses of chemotherapy

BACKGROUND

In order to analyze the clinical activity and cost-effectiveness of granulocyte colony-stimulating factors (G-CSF), the prophylactic usage of G-CSF in patients treated with a single chemotherapy regimen during early courses was prospectively evaluated.

METHODS

Thirty patients with newly diagnosed non-Hodgkin lymphoma (NHL) treated with the first course of an R-CHOP regimen were enrolled randomly. After treatment with the first course of chemotherapy, a daily dose of G-CSF (lenograstim, 100 μg) was administered to half (15 cases) of the patients, and a dose of G-CSF (100 μg) was administered every other day to the other half of the patients when leukocytopenia (<1.5 × 10(9)/L) and/or neutropenia (<0.5 × 10(9)/L) occurred. Changes in leukocyte and neutrophil counts, prophylaxis, febrile neutropenia (FN) events, and cost performance between the two groups were analyzed.

RESULTS

No significant difference between the two groups was observed in recoveries of leukocyte and neutrophil counts and evidence of FN. The only difference was the total cost of G-CSF.

CONCLUSION

We concluded that every-other-day use of G-CSF was as clinically effective for the prophylaxis of FN as the daily use of G-CSF, and economically speaking, the administration of G-CSF every other day should be more beneficial for patients with NHL during early courses of R-CHOP chemotherapy.

Inductive potential of recombinant human granulocyte colony-stimulating factor to mature neutrophils from x-irradiated human peripheral blood hematopoietic progenitor cells

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) has been used for treatment of neutropenia. Filgrastim, Nartograstim, and Lenograstim are clinically available in Japan. However, the differences in potential benefit for radiation-induced disorder between these types of rhG-CSFs remain unknown. Therefore, the effects of three different types of rhG-CSFs on granulocyte progenitor cells and expansion of neutrophils from nonirradiated or 2 Gy X-irradiated human CD34+ hematopoietic progenitor cells were examined. For analysis of granulocyte colony-forming units (CFU-G) and a surviving fraction of CFU-G, nonirradiated or X-irradiated CD34+ cells were cultured in methylcellulose containing rhG-CSF. These cells were cultured in serum-free medium supplemented with rhG-CSF, and the expansion and characteristics of neutrophils were analyzed. All three types of rhG-CSFs increased the number of CFU-G in a dose-dependent manner; however, Lenograstim is superior to others because of CFU-G-derived colony formation at relatively low doses. The surviving fraction of CFU-G was independent of the types of rhG-CSFs. Expansion of neutrophils by rhG-CSF was largely attenuated by X-irradiation, though no significant difference in neutrophil number was observed between the three types of rhG-CSFs under both nonirradiation and X-irradiation conditions. In terms of functional characteristics of neutrophils, Lenograstim-induced neutrophils produced high levels of reactive oxygen species compared to Filgrastim, when rhG-CSF was applied to nonirradiated CD34(+) cells. In conclusion, different types of rhG-CSFs lead to different effects when rhG-CSF is applied to nonirradiated CD34+ cells, though Filgrastim, Nartograstim, and Lenograstim show equal effects on X-irradiated CD34+ cells.