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Background: F-627 (efbemalenograstim alfa) is a novel long acting granulocyte colony-stimulating factor (G-CSF) that contains two human G-CSF fused to a human immunoglobulin G2 (hIgG2) -Fc fragment with a peptide linker. This studyevaluated the efficacy and safety of F-627, also known as efbemalenograstim alfa (Ryzneuta®) in reducing neutropenia compared with filgrastim (GRAN®). Methods: This was a multicenter, randomized, open-label, active-controlled non-inferiority study. Two hundred thirty nine (239) patients were enrolled in thirteen centers and received the chemotherapy with epirubicin (100 mg/m2) and cyclophosphamide (600 mg/m2) on day 1 of each cycle for a maximum of four cycles. Patients were randomized to receive either a single 20 mg subcutaneous (s.c.) injection of F-627 on day 3 of each cycle or daily s.c. injection of filgrastim 5 µg/kg/d starting from day 3 of each cycle. The primary endpoint was the duration of grade 3 or 4 neutropenia in cycle 1. The safety profile was also evaluated. Results: The mean (SD) duration of grade 3 or 4 neutropenia in cycle 1 was 0.68 (1.10) and 0.71 (0.95) days for the F-627 and the filgrastim groups, respectively. The Hodges-Lehmann estimate of the between-group median difference (F-627 vs filgrastim) in the duration of grade 3 or 4 neutropenia in cycle 1 was 0 day and the upper limit of the one-sided 97.5% CI was 0 day, which was within the prespecified non-inferiority margin of 1-day. Results for all efficacy endpoints in cycles 2 − 4 were consistent with the results in cycle 1, however a trend towards a lower incidence and a shorter duration of grade 3 or 4 neutropenia and grade 4 neutropenia was observed in the F-627 group compared with the filgrastim group. The ANC nadir in the F-627 group was significantly higher than that in the filgrastim group in each cycle. A single fixed dose of F-627 was well tolerated and as safe as standard daily filgrastim. Conclusions: A single fixed dose of 20 mg of F-627 in each cycle was as safe and effective as a daily dose of filgrastim 5 µg/kg/d in reducing neutropenia and its complications in patients who received four cycles of EC. Trial registration: ClinicalTrials.gov: NCT04174599, on 22/11/2019. [ABSTRACT FROM AUTHOR]

Background: Current guidelines recommend using filgrastim or tbo‐filgrastim to mobilize hematopoietic progenitor cells in an autologous setting. However, previous studies have suggested other forms of granulocyte colony‐stimulating factor (G‐CSF) are equally efficacious, possibly with fewer leukaphereses required. Thus, we prospectively studied the efficacy of lenograstim, a glycosylated recombinant form of G‐CSF, in multiple myeloma (MM) patients. Methods: From November 2011 to January 2020, 98 MM patients undergoing autologous stem cell transplant (ASCT) from five academic centers in Korea were enrolled. Patients were mobilized with subcutaneous lenograstim (Neutrogin®) with fixed doses of 10 μg/kg for 4 days. Results: Most of the patients (N = 90, 91.8%) achieved at least the targets of 2 × 106 CD34+ cells/kg body weight, and more than half of MM patients (N = 57, 58.2%) reached a target of 5 × 106 CD34+ cells/kg body weight. The mobilization failure rate was 8.2% (N = 8). The median number of CD34 + cell/kg using G‐CSF only was 5.25 × 106/kg (range 0.49–13.47). Adverse events included transfusion (TF, N = 53, 54.1%), bone pain (N = 6, 6.1%), fever (N = 2, 2.0%), and gastrointestinal troubles (N = 2, 2.0%). There were no grade 3 or 4 adverse events during mobilization. Body surface area (BSA) at mobilization and platelet TF were factors associated with CD34+ collection. Most patients achieved neutrophil (N = 93, 98.9%) and platelet (N = 89, 95.7%) engraftment. Conclusion: Lenograstim can safely and effectively mobilize stem cells in MM autologous settings. [ABSTRACT FROM AUTHOR]

Over the past 20 years, granulocyte colony-stimulating factor (G-CSF) has driven the attention of researchers as a therapeutic agent for curing patients suffering from neutropenia. Despite the successful use of G-CSF, it currently requires daily injections, which are inconvenient, expensive, and distressing for children. Therefore, an alternative strategy for using G-CSF for treatment is needed. Understanding the G-CSF structure, expression, mechanism of action, and how it induces neutrophils mobilization is crucial to producing promising cancer therapy. The ability of G-CSF to mobilize hematopoietic stem cells from the bone marrow into the blood circulation was consequently exploited and altered the practice of hematopoietic stem cell transplantation. This is the motivation for the current review, which sheds light on the history of G-CSF and then focuses on the mechanism of action upon binding to its receptor (G-CSFR) and how that had led to the stimulation of neutrophils mobilization. The findings of this review show new insight into the mechanism of G-CSF that induces neutrophils mobilization. Thus, Understanding the G-CSF will provide a more effective treatment for all neutropenia patients. [ABSTRACT FROM AUTHOR]

The granulocyte colony-stimulating factor (G-CSF) is a hematopoietic cytokine that has important clinical applications for treating neutropenia. Nartograstim is a recombinant variant of human G-CSF. Nartograstim has been produced in Escherichia coli as inclusion bodies (IB) and presents higher stability and biological activity than the wild type of human G-CSF because of its mutations. We developed a production process of nartograstim in a 10-L bioreactor using auto-induction or chemically defined medium. After cell lysis, centrifugation, IB washing, and IB solubilization, the following three refolding methods were evaluated: diafiltration, dialysis, and direct dilution in two refolding buffers. Western blot and SDS-PAGE confirmed the identity of 18.8-kDa bands as nartograstim in both cultures. The auto-induction medium produced 1.17 g/L and chemically defined medium produced 0.95 g/L. The dilution method yielded the highest percentage of refolding (99%). After refolding, many contaminant proteins precipitated during pH adjustment to 5.2, increasing purity from 50 to 78%. After applying the supernatant to cation exchange chromatography (CEC), nartograstim recovery was low and the purity was 87%. However, when the refolding solution was applied to anion exchange chromatography followed by CEC, 91%–98% purity and 2.2% recovery were obtained. The purification process described in this work can be used to obtain nartograstim with high purity, structural integrity, and the expected biological activity. Key points: • Few papers report the final recovery of the purification process from inclusion bodies. • The process developed led to high purity and reasonable recovery compared to literature. • Nartograstim biological activity was demonstrated in mice using a neutropenia model. [ABSTRACT FROM AUTHOR]

Background: Stem cell factor (SCF) and granulocyte-colony stimulating factor (G-CSF) are well-characterized vital hematopoietic growth factors that regulate hematopoiesis. G-CSF and SCF synergistically exhibit a stimulatory effect on hematopoietic progenitors. The combination of G-CSF and SCF has been used for mobilization of peripheral blood progenitor cells in cancer and non-cancerous conditions. To overcome challenges connected with the administration of two cytokines, we developed two fusion proteins composed of human SCF and human G-CSF interspaced by an alpha-helix-forming peptide linker. Methods: The recombinant proteins SCF-La-GCSF and GCSF-La-SCF were purified in three steps using an ion-exchange and mixed-mode chromatography. The purity and quantity of the proteins after each stage of purification was assessed using RP-HPLC, SDS-PAGE, and the Bradford assays. Purified proteins were identified using high-performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS) and the Western blot analyses. The molecular weight was determined by size exclusion HPLC (SE-HPLC). The activity of heterodimers was assessed using cell proliferation assays in vitro. The capacity of recombinant fusion proteins to stimulate the increase of the absolute neutrophil count in rats was determined in vivo. The binding kinetics of the proteins to immobilized G-CSF and SCF receptors was measured using total internal refiection ellipsometry and evaluated by a standard Langmuir kinetics model. Results: The novel SCF-La-GCSF and GCSF-La-SCF proteins were synthesized in Escherichia coli. The purity of the heterodimers reached >90% as determined by RP-HPLC. The identity of the proteins was confirmed using the Western blot and HPLC/ESI-MS assays. An array of multimeric forms, non-covalently associated dimers or trimers were detected in the protein preparations by SE-HPLC. Each protein induced a dose-dependent proliferative response on the cell lines. At equimolar concentration, the heterodimers retain 70-140% of the SCF monomer activity (p ≤ 0.01) in promoting the M-07e cells proliferation. The G-CSF moiety in GCSF-La-SCF retained 15% (p ≤ 0.0001) and in SCF-La-GCSF retained 34% (p ≤ 0.01) of the monomeric G-CSF activity in stimulating the growth of G-NFS-60 cells. The obtained results were in good agreement with the binding data of each moiety in the fusion proteins to their respective receptors. The increase in the absolute neutrophil count in rats caused by the SCF-La-GCSF protein corresponded to the increase induced by a mixture of SCF and G-CSF. [ABSTRACT FROM AUTHOR]

In spite of the recent focus on the development of novel targeted drugs to treat cancer, cytotoxic chemotherapy remains the standard treatment for the vast majority of patients. Unfortunately, chemotherapy is associated with high hematopoietic toxicity that may limit its efficacy. We have previously established potential strategies to mitigate chemotherapy-induced neutropenia (a lack of circulating neutrophils) using a mechanistic model of granulopoiesis to predict the interactions defining the neutrophil response to chemotherapy and to define optimal strategies for concurrent chemotherapy/prophylactic granulocyte colony-stimulating factor (G-CSF). Here, we extend our analyses to include monocyte production by constructing and parameterizing a model of monocytopoiesis. Using data for neutrophil and monocyte concentrations during chemotherapy in a large cohort of childhood acute lymphoblastic leukemia patients, we leveraged our model to determine the relationship between the monocyte and neutrophil nadirs during cyclic chemotherapy. We show that monocytopenia precedes neutropenia by 3 days, and rationalize the use of G-CSF during chemotherapy by establishing that the onset of monocytopenia can be used as a clinical marker for G-CSF dosing post-chemotherapy. This work therefore has important clinical applications as a comprehensive approach to understanding the relationship between monocyte and neutrophils after cyclic chemotherapy with or without G-CSF support. [ABSTRACT FROM AUTHOR]

Recombinant form of granulocyte colony stimulating factor (G-CSF) was first approved by FDA in 1998 for chemotherapy induced neutropenia. However, despite production of its biosimilars, less expensive production of G-CSF could reduce the overall therapeutic cost. The aim of this study was to evaluate the possibility of producing biologically active recombinant G-CSF via a single step purification procedure mediated by a self-cleavable intein. G-CSF was expressed by E. coli BL21 (DE3) through IPTG induction, followed by its purification using pH optimization on a chitin column. Western blotting, ELISA, size exclusion chromatography, circular diachorism, peptide mapping, and in vitro assays were performed to compare the structural similarity and biological activity of the purified G-CSF with Neupogen™. Protein purification was confirmed by revealing a band of approximately 18.8 kDa on SDS-PAGE. Bioactivity and physicochemical assays based on the US pharmacopeia showed almost identical or acceptable ranges of similarities between recombinant G-CSF and Neopogen™. this study, biologically active soluble recombinant G-CSF was successfully produced with high purity without using chaotropic solvents through a one-step procedure. This shorter and more efficient purification procedure can reduce the cost and time of G-CSF production which makes its industrial production more cost-effective and might be also applicable for production of other biopharmaceuticals. [ABSTRACT FROM AUTHOR]

Neutrophils play a major role in tumor biology. Among other functions, neutrophils can release extracellular traps (NETs), mesh-like structures of decondensed chromatin fibers, in a process termed NETosis. Originally characterized as an antimicrobial mechanism, NETosis has been described in cancer, but cancer-related predisposition is not clear. In the current study, we investigated the predisposition of circulating neutrophils to release NETs in lung cancer and the impact of G-CSF on this function, comparing circulating neutrophils isolated from cancer patients to the LLC and AB12 mouse models. We find that neutrophils from both healthy donors and cancer patients display high NETotic potential, with 30–60% of cells undergoing NETosis upon PMA stimulation. In contrast, neutrophils isolated from tumor-bearing mice displayed only 4–5% NETotic cells, though significantly higher than naive controls (1–2%). Despite differential mechanisms of activation described, Ionomycin and PMA mainly triggered suicidal rather than vital NETosis. G-CSF secreting tumors did not increase NETotic rates in murine neutrophils, and direct G-CSF stimulation did not promote their NET release. In contrast, human neutrophils strongly responded to G-CSF stimulation resulting also in a higher response to PMA + G-CSF stimulation. Our data show clear differences in NETotic potentials between human and murine neutrophils. We do not find a predisposition of neutrophils to release NETs in lung cancer patients compared to healthy controls, whereas cancer may modulate neutrophils' NETotic potential in mice. G-CSF secreted from tumors differentially affects murine and human NETosis in cancer. These important differences should be considered in future studies of NETosis in cancer. [ABSTRACT FROM AUTHOR]

Recent studies reported granulocyte colony-stimulating factor (G-CSF) treatment can improve the cognitive function of Alzheimer's disease (AD) mice, and the mobilized hematopoietic stem cells (HSCs) or bone marrow mesenchymal stem cells (BM-MSCs) are proposed to be involved in this recovery effect. However, the exact role of mobilized HSC/BM-MSC in G-CSF-based therapeutic effects is still unknown. Here, we report that C-X-C chemokine receptor type 4 (CXCR4)/stromal cell-derived factor 1 (SDF-1) chemotaxis was a key mediator in G-CSF-based therapeutic effects, which was involved in the recruitment of repair-competent cells. Furthermore, we found both mobilized HSCs and BM-MSCs were able to infiltrate into the brain, but only BM-MSCs replenished the neural lineage cells and contributed to neurogenesis in the brains of AD mice. Together, our data show that mobilized BM-MSCs are involved in the replenishment of neural lineages following G-CSF treatment via CXCR4/SDF-1 chemotaxis and further support the potential use of BM-MSCs for further autogenically therapeutic applications. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) is an activator of neutrophil granulocytes. Neutrophil extracellular traps are a defensive mechanism consisting of neutrophils, platelets, DNA, histones and antimicrobial proteins. This study was performed to determine whether G-CSF increases histone-complexed DNA in the plasma of healthy volunteers. In total, 51 healthy volunteers (25 males and 26 females) were treated with G-CSF (18 with 300 µg single dose i.v., 27 with 5 µg/kg s.c. for 4 days) and six participants received a placebo. Histone-complexed DNA was measured by enzyme immunoassay in plasma samples at predefined time points (0, 2, 4, 6, 24 h after single dose, day 1, day 2 and day 5 after repeated doses). Histone levels were quantified by Western blotting. A single dose of G-CSF rapidly increased hc-DNA by about 50 % ( p < 0.05 for 2-24 h). After repeated doses the increase was even more pronounced: hc-DNA increased by about 50 % (3.0 ± 0.9, p < 0.001 after 24 h and about fourfold after 96 h ( p < 0.001)). A statistical significant increase in histone levels was detected as early as 4 h after G-CSF injection (0.43 ± 0.2 vs. 1.08 ± 0.3 µg/ml; p = 0.034). In the placebo group no significant changes occurred. Moreover, significantly higher levels of hc-DNA were measured in male compared to female subjects (226 ± 43 vs. 84 ± 19, p < 0.001). G-CSF injection substantially increases hc-DNA levels in healthy volunteers. There is a significant gender difference in hc-DNA at the baseline. [ABSTRACT FROM AUTHOR]

We develop a physiological model of granulopoiesis which includes explicit modelling of the kinetics of the cytokine granulocyte colony-stimulating factor (G-CSF) incorporating both the freely circulating concentration and the concentration of the cytokine bound to mature neutrophils. G-CSF concentrations are used to directly regulate neutrophil production, with the rate of differentiation of stem cells to neutrophil precursors, the effective proliferation rate in mitosis, the maturation time, and the release rate from the mature marrow reservoir into circulation all dependent on the level of G-CSF in the system. The dependence of the maturation time on the cytokine concentration introduces a state-dependent delay into our differential equation model, and we show how this is derived from an age-structured partial differential equation model of the mitosis and maturation and also detail the derivation of the rest of our model. The model and its estimated parameters are shown to successfully predict the neutrophil and G-CSF responses to a variety of treatment scenarios, including the combined administration of chemotherapy and exogenous G-CSF. This concomitant treatment was reproduced without any additional fitting to characterize drug-drug interactions. [ABSTRACT FROM AUTHOR]

Neutropenia and febrile neutropenia are two major complications of chemotherapy. Dose reductions, delays in treatment administration, and the use of granulocyte colony-stimulating factors are equally recommended options to preserve absolute neutrophil count in case of chemotherapy regimens bringing a risk of febrile neutropenia of 20% or higher. Recombinant granulocyte colony-stimulating factors, such as filgrastim and lenograstim, have a short elimination half-life (t1/2) and need to be used daily, while others, like pegfilgrastim and lipegfilgrastim, are characterized by a long t1/2 requiring only a single administration per cycle. Balugrastim is a novel long-acting recombinant granulocyte colony-stimulating factor obtained by means of a genetic fusion between recombinant human serum albumin and granulocyte colony-stimulating factor. Albumin binding increases the molecular weight and determines a high plasmatic stability leading to a t1/2 of ~19 days. Balugrastim's efficacy, safety, and tolerability have been assessed in four different clinical trials involving breast cancer patients treated with doxorubicin and docetaxel. Pegfilgrastim was chosen as a comparator. Balugrastim was noninferior to pegfilgrastim with regard to the reduction of mean duration of severe neutropenia during cycle 1. Moreover, both treatments were comparable in terms of efficacy and safety profile. Balugrastim was well tolerated, with the only related adverse event being mild to moderate bone pain. The aim of this review is to summarize the currently available literature data on balugrastim. [ABSTRACT FROM AUTHOR]

This paper traces the experimental, clinical and mathematical modeling efforts to understand a periodic hematological disease-cyclical neutropenia. It is primarily a highly personal account by two scientists from quite different backgrounds of their interactions over almost 40 years and their attempts to understand this intriguing disease. It's also a story of their efforts to offer effective treatments for the patients who suffer from cyclic neutropenia and other conditions causing neutropenia and infections. [ABSTRACT FROM AUTHOR]

Bi-weekly (R)-CHOP therapy is one of the standard treatmentS for elderly patients with aggressive B-cell lymphoma, but it is only feasible with supportive G-CSF treatment. In the trials of the DSHNHL, either unpegylated G-CSF was given daily over 7 or 10 days or pegylated G-CSF was applied at day 4 of each cycle. These schedules were planned on the basis of simulations of a biomathematical pharmacokinetic/pharmacodynamic model. By analysing the observed data, we investigated whether our model predictions were correct and whether even better schedules can be proposed. We used data on 249 matched patients of two prospective trials, RICOVER-60 and PEGFILGRASTIM. The three G-CSF-schedules showed similar outcomes regarding leukocytopenia, infections and days in hospital, with pegylated G-CSF having slightly but not significantly better scores in all three endpoints. Regarding pegylated G-CSF, the best timing is predicted to be any day between days 4 and 7. With respect to unpegylated G-CSF, the starting day is less important, but it should be continued until the end of each cycle.The three G-CSF-schedules are interchangeable in (R)-CHOP-14 for elderly patients with aggressive B-cell lymphoma. Our model correctly predicts time courses of leukocytes. Further model predictions are presented, which can be tested in subsequent clinical trials. [ABSTRACT FROM AUTHOR]

The human granulocyte colony stimulating factor (hG-CSF) plays an important role in hematopoietic cell proliferation/differentiation and has been widely used as a therapeutic agent for treating neutropenias. Nartograstim is a commercial G-CSF that presents amino acid changes in specific positions when compared to the wild-type form, which potentially increase its activity and stability. The aim of this work was to develop an expression system in Escherichia coli that leads to the production of large amounts of a recombinant hG-CSF (rhG-CSF) biosimilar to Nartograstim. The nucleotide sequence of hg- csf was codon-optimized for expression in E. coli. As a result, high yields of the recombinant protein were obtained with adequate purity, structural integrity and biological activity. This protein has also been successfully used for the production of specific polyclonal antibodies in mice, which could be used in the control of the expression and purification in an industrial production process of this recombinant protein. These results will allow the planning of large-scale production of this mutant version of hG-CSF (Nartograstim), as a potential new biosimilar in the market. [ABSTRACT FROM AUTHOR]

Myeloid colony-stimulating factors (M-CSFs), which include granulocyte colony-stimulating factor (G-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF), regulate the proliferation and differentiation of myeloid cells. Their use has an important role in the treatment of hematologic malignancies. Guidelines for the use of colony stimulating factors have been published by the American Society of Oncology (ASCO) in 1996 and have been updated several times, most recently in 2006. Meta-analyses of randomized controlled trials are regarded as the highest grade of evidence in clinical research and as such, compared to individual studies, they have more power in answering unresolved clinical issues. In this review, our aim is to evaluate the role of M-CSFs in hematologic malignancies based on meta-analyses conducted in the field. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Further to the patent expiry of Neupogen (Amgen filgrastim), Hospira has developed a biosimilar filgrastim (Nivestim) that may offer a clinically effective alternative for multiple hematologic and oncologic indications. Here results are reported from a phase I trial, primarily designed to compare the pharmacodynamic profiles of Hospira filgrastim and Amgen filgrastim. A phase I, single-center, double-blind, randomized trial was undertaken to demonstrate equivalence of the pharmacodynamic characteristics of Hospira filgrastim and Amgen filgrastim. Fifty healthy volunteers were randomized to receive 5 or 10 microg/kg dosing, before further randomization to treatment sequence. All volunteers received five daily subcutaneous doses of Hospira filgrastim or Neupogen, with subsequent crossover to the alternative treatment. Bioequivalence was evaluated by analysis of variance; if the estimated 90% confidence intervals (CIs) for the ratio of 'test' to 'reference' treatment means were within the conventional equivalence limits of 0.80-1.25, then bioequivalence was concluded. Forty-eight volunteers completed the study. Geometric mean absolute neutrophil count area under the curve from time 0 to the last time point at day 5 (primary endpoint) was comparable in volunteers given Hospira filgrastim or Amgen filgrastim at 5 microg/kg (ratio of means, 0.98; 90% CI, 0.92-1.05) or 10 microg/kg (ratio, 0.97; 90% CI, 0.93-1.01); 90% CIs were within the predefined range necessary to demonstrate bioequivalence. Hospira filgrastim was well tolerated with no additional safety concerns over Amgen filgrastim. Hospira filgrastim is bioequivalent with Amgen filgrastim with regard to its pharmacodynamic characteristics. [ABSTRACT FROM AUTHOR]

Recombinant human granulocyte colony-stimulating factor (filgrastim) has multiple hematologic and oncologic indications as Neupogen (Amgen filgrastim). Hospira has developed a biosimilar filgrastim (Nivestim). Here, results are reported from a phase I trial, primarily designed to compare the pharmacokinetic profiles of Hospira filgrastim and Amgen filgrastim. A phase I, single-center, open-label, randomized trial was undertaken to demonstrate equivalence of the pharmacokinetic characteristics of Hospira filgrastim and Amgen filgrastim. Forty-eight healthy volunteers were randomized to receive intravenous (i.v.) or subcutaneous (s.c.) dosing and then further randomized to order of treatment. Volunteers in each of the two dosing groups received a single 10microg/kg dose of Hospira filgrastim or Amgen filgrastim, with subsequent crossover. Bioequivalence was evaluated by analysis of variance; if the estimated 90% confidence intervals (CIs) for the ratio of 'test' to 'reference' treatment means were within the conventional equivalence limits of 0.80-1.25, then bioequivalence was concluded. Forty-six volunteers completed the study. Geometric mean area under the curve from time 0 to the last time point (primary endpoint) was similar in volunteers given Hospira filgrastim or Amgen filgrastim following i.v. (ratio of means: 0.96; 90% CI: 0.90-1.02) or s.c. (ratio of means: 1.02; 90% CI: 0.95-1.09) dosing; 90% CIs were within the predefined range necessary to demonstrate bioequivalence. Hospira filgrastim was well tolerated with no additional safety concerns over Amgen filgrastim. Hospira filgrastim is bioequivalent with Amgen filgrastim in terms of its pharmacokinetic properties and may provide a clinically effective alternative. [ABSTRACT FROM AUTHOR]

Recombinant human (rHu) G-CSF has been widely used to treat neutropenia and mobilize PBPCs for their autologous and allogeneic transplantation. It shortens neutropenia and thus reduces the frequency of neutropenic fever. We compared the efficiency of glycosylated rHu and non-glycosylated Hu G-CSF in mobilizing hematopoietic progenitor cells (HPCs). In total, 86 patients were consecutively enrolled for mobilization with CY plus either glycosylated or non-glycosylated G-CSF, and underwent leukapheresis. The HPC content of each collection, toxicity, days of leukapheresis needed to reach the minimum HPC target and days to recover WBC (500 and >1000/mm3) and plts (>50 000/mm3) were evaluated. Glycosylated G-CSF mobilized more CD34+ cells than did the non-glycosylated form. The ability to reach a collection target of >3 × 106 CD34+/kg body weight in two leukaphereses was higher for glycosylated G-CSF. No significant differences between the two regimens were observed with regard to toxicity and days to WBC and plt recovery. High-dose CY plus glycosylated G-CSF achieved adequate mobilization and the collection target more quickly and with fewer leukaphereses. [ABSTRACT FROM AUTHOR]

We previously reported that under the stress condition caused by the addition of 2-hydroxyethyl disulfide, a thiol-specific oxidant, to growing cultures of Escherichia coli BL21(DE3), a population of stress-responsive proteins [peptidyl-prolyl cis– trans isomerase B (PpiB), bacterioferritin (Bfr), putative HTH-type transcriptional regulator yjdC (YjdC), dihydrofolate reductase (FolA), chemotaxis protein cheZ (CheZ), and glutathione synthetase (GshB)] were significantly upregulated when compared with the nonstress condition. When those stress-responsive proteins were used as fusion partners for the expression of human granulocyte colony-stimulating factor (hG-CSF), the solubility of hG-CSF was dramatically enhanced in E. coli cytoplasm, whereas almost all of the directly expressed hG-CSF were aggregated to inclusion bodies. In addition, the spectra of circular dichroism measured with the purified hG-CSF were identical to that of standard hG-CSF, implying that the synthesized hG-CSF has native conformation. These results indicate that the bacterial stress-responsive proteins could be potent fusion expression partners for aggregation-prone heterologous proteins in E. coli cytoplasm. [ABSTRACT FROM AUTHOR]

A complete resection of a hepatocellular carcinoma (HCC) producing the granulocyte colony-stimulating factor (G-CSF) was performed and is reported here. The patient had a few general symptoms and complications, such as the paraneoplastic syndrome. He had marked granulocytosis, and his serum levels of G-CSF and interleukin-6 were elevated. The pathological findings of the resected specimen revealed poorly differentiated HCC with sarcomatous change and showed, immunohistochemically, staining of G-CSF. Only a few cases of G-CSF-producing HCC have been reported, and they resulted in rapid tumour growth and poor prognosis. The case presented here may be the first complete resection ever performed, but the patient's prognosis was similar to that observed in typical cases. [ABSTRACT FROM AUTHOR]

This analysis was conducted to characterize the pharmacokinetics and pharmacodynamics of pegfilgrastim and to develop a pharmacokinetic-pharmacodynamic model to describe the granulopoietic effects of pegfilgrastim and the homeostatic regulation of pegfilgrastim clearance in healthy subjects. Pegfilgrastim serum concentration data and differential white cell counts were obtained from an open-label, single-dose, dose escalation study. Healthy subjects (8 subjects/dose group) received a single subcutaneous dose of 30, 60, 100, or 300 µg/kg pegfilgrastim. Pegfilgrastim exhibited nonlinear pharmacokinetics; clearance decreased with increasing dose. A dose-dependent increase in absolute neutrophil count with an increase in the percentage of band cells was observed. A pharmacokinetic-pharmacodynamic model was developed that adequately described the nonlinear pharmacokinetics of pegfilgrastim, feedback regulation of pegfilgrastim clearance by neutrophils, and the differential effects of pegfilgrastim on neutrophil populations in blood. [ABSTRACT FROM PUBLISHER]

Mobilization of CD34+ into peripheral blood is attained by either glycosylated (lenograstim) or non-glycosylated recombinant G-CSF (filgrastim). 101 donors, 57 males, median age 42 years (range 16-63) entered this retrospective study. Group I (55 cases) received filgrastim and group II lenograstim subcutaneously for 5-6 days. The peak number of CD34+ cells/μl blood observed on day 4 and 5 was not significantly different in the two groups. No differences were shown in terms of both circulating CFU-GM at the time of harvesting and CD34+ target of collection. The most frequent side effects were bone pain (18.2% grade I; 36.4% grade II, 7.3% grade III), headache (18.2%), nausea (9.1%), fever (5.5%) and a mild splenomegaly (>2cm) (5.5%) in filgrastim group, and bone pain (37.0% grade I, 26.1% grade II, 2.2% grade III), headache (17.4%), nausea (15.2%), fever (4.4%) and a mild splenomegaly (4.3%) in lenograstim group, respectively. CD34+ collection was associated with thrombocytopenia, which was not significantly different between the two groups. No donor in either group developed long-term adverse effects. We conclude that both G-CSFs are comparable in terms of CD34+ cell collection, safety and tolerability. J. Clin. Apheresis © 2005 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Abstract: We tested capabilities of drugs elevating extracellular adenosine and of granulocyte colony-stimulating factor (G-CSF) given alone or in combination to modulate regeneration from severe myelosuppression resulting from combined exposure of mice to ionizing radiation and carboplatin. Elevation of extracellular adenosine was induced by joint administration of dipyridamole (DP), a drug inhibiting the cellular uptake of adenosine, and adenosine monophosphate (AMP), serving as an adenosine prodrug. DP + AMP, G-CSF or all these drugs in combination were administered in a 4-d treatment regimen starting on day 3 after induction of myelosuppression. Comparable enhancements of haematopoietic regeneration due to elevation of extracellular adenosine or to action of G-CSF were demonstrated as shown by elevated numbers of haematopoietic progenitor cells for granulocytes/macrophages (GM-CFC) and erythrocytes (BFU-E) in the bone marrow and spleen in early time intervals after termination of the drug treatment, i.e. on days 7 and 10 after induction of myelosuppression. Coadministration of all the drugs further potentiated the restoration of progenitor cell pools in the haematopoietic organs. The effects of the drug treatments on progenitor cells were reflected in the peripheral blood in later time intervals of days 15 and 20 after induction of myelosuppression, especially as significantly elevated numbers of granulocytes and less pronounced elevation of lymphocytes and erythrocytes. The results substantiate the potential of drugs elevating extracellular adenosine for clinical utilization in myelosuppressive states, e.g. those accompanying oncological radio- and chemotherapy. [ABSTRACT FROM AUTHOR]

We have developed a transgenic female goat harboring goat beta-casein promoter/human granulocyte colony stimulating factor (G-CSF) fusion gene by microinjection into fertilized one-cell goat zygotes. Human G-CSF was produced at levels of up to 50 μ g/ml in transgenic goat milk. Its biological activity was equivalent to recombinant human G-CSF expressed from Chinese hamster ovary (CHO) cell when assayed using in vitro HL-60 cell proliferation. Human G-CSF from transgenic goat milk increased the total number of white blood cells in C57BL/6N mice with leucopenia induced by cyclophosphamide (CPA). The secreted human G-CSF was glycosylated although the degree of O-glycosylation was lower compared to CHO cell-derived human G-CSF. [ABSTRACT FROM AUTHOR]

Patients with neutropenia, especially neutropenia following aggressive myeloablative therapy, are at high risk for developing infectious complications caused by bacteria and opportunistic fungi. Infections remain one of the leading causes of treatment failure in patients with cancer. Thus, new and innovative therapeutic strategies are needed for management of neutropenic patients with infection. Because neutrophils represent the first line of host defense, granulocyte transfusion therapy should be a logical therapeutic approach. Although such therapy has been employed sporadically for several decades, clinical benefit has been compromised by technical problems and low granulocyte yields resulting from inadequate donor stimulation. The discovery of granulocyte colony-stimulatng factor (G-CSF) as a means to elevate blood neutrophil counts when administered to normal donors has rekindled interest in granulocyte transfusion therapy. Extensive experience has been gained worldwide with G-CSF in clinical practice, and adverse events have been minimal when G-CSF has been administered to patients or healthy persons in human trials. This review focuses on the use of G-CSF in granulocyte transfusion therapy, including technical considerations of granulocyte leukapheresis and storage, donor selection and stimulation, as well as treatment results and associated risks. [ABSTRACT FROM AUTHOR]

We analyzed the expression of cell surface antigens and granulocyte colony-stimulating factor (G-CSF) receptors using flow cytometry, the expression of G-CSF mRNA receptor, using reverse transcription (RT)-PCR, and tested the effect of G-CSF on leukemia colony formation. A total of 14 lymphocytic leukemia patients were examined, seven with acute lymphocytic leukemia (ALL), two with adult T-cell leukemia (ATL), two with B-chronic lymphocytic leukemia (CLL), two with chronic myelocytic leukemia in lymphoid blastic crisis (CML-LBC), and one with plasma cell leukemia (PCL). The presence of G-CSF receptors was demonstrated in 4/14 (29%) patients, two with ALL, one with CLL, and one with CML-LBC, and was associated with stimulation of leukemia clonogenic cell growth by G-CSF. In addition, all four positive leukemia cell types expressed typical B-cell antigens. Our results indicated that G-CSF receptors are expressed on some portion of B-lymphoid leukemia and that their receptors are functional as growth stimulators. [ABSTRACT FROM AUTHOR]

We report a patient with refractory anemia with excess blasts who showed a lineage-unrestricted hematologic response to granulocyte colony-stimulating factor (G-CSF). After 17 months of a stable disease state, the patient developed pneumonia, progression of cytopenia, and reduced cellularity and blast mass in the bone marrow. He was given G-CSF to overcome the pneumonia. Not only the neutrophil count, but also the platelet count increased soon after initiation of the G-CSF therapy; both counts became normal on the fifth day of the G-CSF therapy. Additionally, the anemia improved gradually. The neutrophil and platelet counts were maintained in the normal range for 3 months after cessation of the G-CSF. In vitro studies showed that G-CSF alone stimulated megakaryocyte colony formation from bone marrow mononuclear cells (BMMNC), and accessory cells in the BMMNC were necessary for expression of this G-CSF-induced in vitro megakaryocytopoiesis. These results suggest that, in coordination with accessory cells, G-CSF stimulated megakaryocytopoiesis in the patient. This case provides valuable information for understanding the mechanisms of a lineage-unrestricted hematologic response to G-CSF, which is very rarely observed in MDS. [ABSTRACT FROM AUTHOR]

Five patients with drug-induced agranulocytosis received 300 micrograms recombinant human granulocyte colony-stimulating factor (rh G-CSF) subcutaneously twice daily for 2-5 days. G-CSF therapy resulted in a steep increase of the neutrophil count, which was faster than that in patients with spontaneous recovery reported in the literature. In all four patients with infectious complications fever rapidly declined with the increase of granulocytes. G-CSF may be useful in the management of drug-induced agranulocytosis. [ABSTRACT FROM AUTHOR]

To evaluate the effect of colony-stimulating factors and interferon gamma on the oxidative burst capacity of neutrophils in chronic granulomatous disease (CGD) we studied the neutrophils of a patient with variant CGD both from peripheral blood and from bone marrow culture on day 7 and 14. The results revealed that preincubation of peripheral neutrophils for 24 h in medium containing recombinant human granulocyte colony-stimulating factor (rhG-CSF), recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF), and recombinant human interferon gamma (rhIFN-gamma) alone or in combination did not improve the maximal oxidative burst activity measured by MTT assay. The colonies of this patient formed in agar assay were either composed of predominantly nitroblue tetrazolium (NBT)-positive cells or completely unable to reduce NBT. Despite variable colony numbers in the presence of different cytokines, the rate of NBT-positive colonies was less than 17% of the total number of colonies. However, more than 72% of the colonies were NBT positive in controls. In liquid culture, bone marrow cells yielded a comparable rate of NBT-positive and -negative populations at day 7. These data indicate that rhG-CSF, rhGM-CSF, and rhIFN-gamma alone or rhG-CSF and rhGM-CSF in combination with rhIFN-gamma are not able to reconstitute the oxidative burst defect in CGD in vitro. Indeed, regarding colony-forming capacity, the bone marrow cells from the patient responded to CSFs as well as those from control donors did. This fact may warrant the administration of hematopoietic growth factors, at least in variant CGD, in order to enhance the absolute number of functionally normal neutrophils. [ABSTRACT FROM AUTHOR]

CARN 750 (injectable acemannan) is a polydispersed β-(1,4)-linked acetylated mannan isolated from the Aloe barbadensis plant. It has multiple therapeutic properties including activity in wound repair and as a biological agent for the treatment of neoplasia in animals as well as the ability to activate macrophages. We report herein that CARN 750 directly or indirectly has significant hematoaugmenting properties. We observed that the subcutaneous administration of CARN 750 significantly increases splenic and peripheral blood cellularity, as well as hematopoietic progenitors in the spleen and bone marrow as determined by the interleukin-3-responsive colony-forming unit culture assay and the high-proliferative-potential colony-forming-cell (HPP-CFC) assay (a measure of primitive hematopoietic precursors) in myelosuppressed (7 Gy) CBL/6 mice. The greatest hematopoietic effect was observed following sublethal irradiation in mice receiving 1 mg CARN 750/animal, with less activity observed at higher or lower doses. Further, CARN 750, following daily injection, has activity equal to or greater than the injection of an optimal dose of granulocyte-colony-stimulating factor (G-CSF) in myelosuppressed mice. In this comparison, significantly greater activity was observed in the splenic and peripheral blood cellularity, and in the frequency and absolute number of splenic HPP-CFC as compared to the mice receiving G-CSF at 3 μg/animal. CARN 750, when administered to myelosuppressed animals. decreased the frequency of lymphocytes with a concomitant significant increase in the frequency of polymorphonuclear leukocytes (PMN). However, owing to the increased cellularity, a significant increase in the absolute number of PMN, lymphocytes, monocytes and platelets was observed, suggesting activity on multiple cell lineages. The latter is the primary difference in activity as compared to G-CSF which has activity predominantly on PMN. [ABSTRACT FROM AUTHOR]

We examined the effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and cefmetazole sodium on survival, neutrophil count, and neutrophil function in rats with peritonitis produced by cecal ligation and puncture. Rats with peritonitis received either rhG-CSF (50 or 100 μg/kg) with or without cefmetazole (50 mg/kg) for 3 days, cefmetazole alone, or no treatment and were evaluated as controls. The mortality rate of all treated rats was significantly lower than that of the untreated rats. The survival rate was 57.1% for the rats given both rhG-CSF and cefmetazole, but there was no significant improvement of survival as compared with cefmetazole therapy alone. Treatment with rhG-CSF at 100 |Gmg/kg caused the circulating neutrophil count to increase significantly. The phagocytic activity for latex beads and neutrophil HO production showed a greater enhancement by phorbol myristate acetate (PMA) in the untreated rats, thus indicating that neutrophils from treated rats were more activated. These findings show that rhG-CSF can improve survival and neutrophil function in rats with peritonitis, while combined therapy with cefmetazole was also found to be beneficial. [ABSTRACT FROM AUTHOR]

The effect of recombinant human granulocyte colony-stimulating factor (rh G-CSF) on bone was evaluated by histomorphometry using Sprague-Dawley rats. rh G-CSF was injected at doses of 0, 50, 150, and 450 microg/kg for 6 weeks. In vivo double fluorochrome labeling was performed before sacrifice. No significant change in body weight was observed. Bone mineral density (BMD) of lumbar vertebrae and femora was significantly decreased in G-CSF-treated groups. In the lumbar vertebra, osteoid surface, osteoid thickness, trabecular thickness, and labeled surface in G-CSF-treated groups were also significantly lower. In addition, osteoclast number and osteoclast surface were significantly higher in the G-CSF-treated groups. The endocortical surface at the mid-tibia showed lower labeled surface and mineral apposition rate in G-CSF-treated groups, without significant changes at the periosteal surface. Furthermore, numerous granulocytes fully occupied the bone marrow area. We conclude that proliferating granulocytes in the bone marrow may inhibit bone-forming cells from contacting the bone surface, resulting in reduction of bone formation; and increased osteoclastic bone resorption induced by G-CSF treatment contributed to the reduction of BMD. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease is associated with mucosal neutrophil recruitment and activatation, mediated in part by arachidonic acid metabolites. G-CSE attenuates the immune response lo sepsis and ameliorates glycogen storage disease Ib-related colitis. These actions may be effected through the shedding of neutrophil adhesion molecules, or inhibition of proinflammatory mediator synthesis. Immune complex colitis was used to evaluate the effect of rhG-CSF on colonic mucosal inflammation, neutrophil recruitment and the generation of eicosanoids. Immune complex colitis was induced in White New Zealand rabbits. Animals were pretreated with rhG-CSF either 24 h before induction, or at induction, with dosages of 50 and 200/&um;g/kg, rhG-CSF caused a time- and dose-dependent neutrophilia in all animals. Pretreatment with rhG-CSF resulted in increased tissue myeloperoxidase levels, despite a histologically similar mucosal polymorphonuclear cell infiltrate between treated and control colitis groups. Leukotriene B4 (LTB4) and thromboxane B2 (TXB2) dialysis fluid levels were lower in treated animals, in particular in the groups receiving two doses (LTB4: both P < 0.01; TXB2: both P < 0.01. Prostaglandin E2 (PGE2) levels in dialysis fluid of the rhG-CSF-treatcd animals showed no difference from controls. In this model of experimental colitis, high-dose therapy with G-CSF resulted in a marked decrease of proinflammatory mediators, but mucosal generation of the protective PGE2 was preserved. These results suggest that prolonged high-dose therapy with G-CSF may have anti-inflammatory effects in colitis. [ABSTRACT FROM AUTHOR]

Effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) against severe infections in cyclophosphamide (CY)-induced neutropenic mice were investigated by its single use or by its combination with cephem antibiotics. Treatment with rhG-CSF increased the number of peripheral blood leucocytes and strikingly shortened the duration of the neutropenic state. Most of the regained population in the peripheral blood leucocytes were neutrophils. Functions of neutrophils, such as phagocytic activity, superoxide release, and expression of Mac-1 molecules, were remarkably enhanced by administration of rhG-CSF. When rhG-CSF was administered to CY induced neutropenic mice before infection, protective effects against various kinds of bacteria were remarkable. On the other hand, such remarkable effects were not observed when rhG-CSF was administered after infections. However, even in the case of post-infectious treatment, a combination therapy of rhG-CSF with cephem antibiotics, particularly with Cefodizime (CDZM), showed a significant improvement in the survival rate and a decrease in the number of viable bacteria in the liver. These results suggest that a combination therapy of rhG-CSF with cephem antibiotics, especially with CDZM. is an efficient regime against severe infections in patients with neutropenia induced by a heavy anti-tumour chemotherapy. [ABSTRACT FROM AUTHOR]

The superoxide (O2--releasing capacity in response to N-formyl-methionyl-leucyl-phenylalanine (FMLP) and the priming effects of recombinant human granulocyte colony-stimulating factor (rhG-CSF) and granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on FMLP-induced O2- release were investigated in neutrophils from 14 patients with myelodysplastic syndromes (MDS). The O2- -releasing capacity in MDS neutrophils varied from patient to patient. As compared with normal neutrophils, the O2--releasing capacity in MDS neutrophils was increased in 9/14 patients, normal in three patients and decreased in two patients. There was no close relationship between the 02--releasing capacity and the peripheral blood neutrophil count or the plasma concentration of C-reactive protein. The priming of neutrophils by rhG-CSF was not observed in five patients, whereas rhGM-CSF primed neutrophils from all patients. The priming effect of rhGM-CSF was consistently greater than that of rhG-CSF in each patient. The intravenous administration of rhG-CSF (300μg/body) to two MDS patients showed an increase in the peripheral blood neutrophil count and enhancement of neutrophil O2- release. These findings demonstrate that the neutrophil O2- -releasing capacity in MDS varies from patient to patient and is not always impaired, and that rhGM-CSF is able to prime neutrophils which never respond to rhG-CSF. [ABSTRACT FROM AUTHOR]

We performed a series of experiments using alanine-scanning mutagenesis to locate side chains within human granulocyte colony-stimulating factor (G-CSF) that are involved in human G-CSF receptor binding. We constructed a panel of 28 alanine mutants that examined all surface exposed residues on helices A and D, as well as all charged residues on the surface of G-CSF. The G-CSF mutants were expressed in a transiently transfected mammalian cell line and quantitated by a sensitive biosensor method. We measured the activity of mutant proteins using an in vitro proliferation assay and an ELISA binding competition assay. These studies show that there is a region of five charged residues on helices A and C employed by G-CSF in binding its receptor, with the most important residue in this binding patch being Glu 19. Both wild-type G-CSF and the E19A mutant were expressed in E. coli. The re-folded proteins were found to have proliferative activities similar to the analagous proteins from mammalian cells: furthermore, biophysical analysis indicated that the E19A mutation does not cause gross structural perturbations in G-CSF. Although G-CSF is likely to signal through receptor homo-dimerization, we found no compelling evidence for a second receptor binding region. We also found no evidence of self-antagonism at high G-CSF concentrations, suggesting that, in contrast to human growth hormone (hGH) and erythropoietin (EPO), G-CSF probably does not signal via a pure 2.1 receptor:ligand complex. Thus, G-CSF, while having a similar tertiary structure to hGH and EPO, uses different areas of the four helix bundle for high-affinity interaction with its receptor. [ABSTRACT FROM AUTHOR]

A 24-year-old woman with osteomyelitis was diagnosed as having p47-phox-deficient chronic granulomatous disease (CGD). The patient showed a marked deficiency of p47-phox, which is very rare in Japan. As the clinical response to various antibiotics including sulfamethoxazole-trimethoprim was not satisfactory, we added recombinant human granulocyte colony-stimulating factor (rhG-CSF) to the treatment protocol. We report the beneficial clinical course of the patient, together with the effect of rhG-CSF on the granulocyte function, and the present report indicates that rhG-CSF is useful for the treatment of antibiotic-resistant infection in the variant type of p47-phox-defective CGD. [ABSTRACT FROM AUTHOR]

The effects of both daily G-CSF administration and subsequent peripheral blood progenitor cell collection (PBPCC) by apheresis on 20 healthy adult donors were studied. All received daily G-CSF (filgrastim) 10 micrograms/kg for 5-7 days by subcutaneous injection. G-CSF administration was well tolerated, except for moderate bone pain and headache. Peak values of CD34+ cells were observed on days 5 (n = 12) or 6 (n = 8). In all donors a significant increase in CD3+, CD4+, CD8+, CD19+, and NK cells was observed on day 5 in relation to the baseline values. CD4/CD8 lymphocyte ratio was unmodified by G-CSF. None of the donors required a central venous line for PBPCC. Immediately after PBPCC, a platelet count below 100 x 10(9)/1 was observed in nine of 18 cases, although in all donors platelet counts were over 100 x 10(9)/1 7 days later. A lymphocytopenia on day 7 following PBPCC was observed, although there was a tendency to achieve baseline values 30-90 days after the procedure. Mean numbers ( +/- SD) of collected cells x 10(6)/kg after a median of two (1-4) apheresis sessions and a median of 20 1 (10-40) processed were: CD34+ 5.5 ( +/- 2.3), CD3+ 326 ( +/- 105), CD4+ 207 ( +/- 64), CD8+ 164 ( +/- 60), CD19+ 88 ( +/- 32), and NK cells 32 ( +/- 14). We conclude that G-CSF administration to healthy donors is a well-tolerated procedure which is associated with (a) obtaining a high number of hematopoietic progenitor cells, and (b) a significant increase in T, B, and NK cells in donors' blood. In addition, PBPCC by apheresis results in a moderate, rapidly reversible, and clinically irrelevant thrombocytopenia and a moderate lymphocytopenia, which tends to resolve within 3 months following the procedure. [ABSTRACT FROM AUTHOR]