A new bioassay for human granulocyte colony-stimulating factor (hG-CSF) using murine myeloblastic NFS-60 cells as targets and estimation of its levels in sera from normal healthy persons and patients with infectious and hematological disorders

[3H]thymidine uptake by NFS-60 cells in microcultures was found to increase in a linear fashion with the increasing doses of purified recombinant human granulocyte colony-stimulating factor (rhG-CSF). Such increases were found neither with rhG-CSF samples pretreated with rabbit anti-rhG-CSF serum nor with other human colony-stimulating factors such as granulocyte-macrophage colony-stimulating factor (hGM-CSF) or macrophage colony-stimulating factor (hM-CSF). Based on these findings, sera from normal persons and patients with severe infections or various hematological disorders were tested after dialysis using this system in order to determine whether G-CSF levels in sera can be estimated or not. In ten normal persons, five patients with acute myelogenous leukemia (AML M1, M2, and M3), five with myelodysplastic syndrome, and four with chronic myelogenous leukemia, no increases in [3H]thymidine uptake were found within the dose range of 0.4 microliters to 50 microliters. In contrast, linear dose responses parallel to a G-CSF standard curve were observed in one patient with a severe bacterial infection, four with aplastic anemia, two with acute myelomonocytic leukemia (AMMoL) (M4), and two with idiopathic neutropenia tested. From the standard curve, the probable levels of G-CSF were calculated as follows: approximately 200 pg/ml with infection, 130-220 pg/ml with aplastic anemia, 150 and 200 pg/ml with AMMoL, and 1120 and 1200 pg/ml with idiopathic neutropenia. The activities of sera were reduced by the anti-rhG-CSF serum pretreatment in the same way as documented in the case of rhG-CSF. Furthermore, the level in a patient with a severe infection became undetectable soon after elimination of the infection and blood neutrophil counts had returned to normal. These findings indicate that the microbioassay system will be useful for measuring circulating G-CSF levels which would fluctuate in accord with requirements for stimulating neutrophil production or with abnormal production of hG-CSF.     

Serum levels of granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor in treated patients with chronic myelogenous leukemia in chronic phase

BACKGROUND: Despite the fact that granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony-stimulating factor (G-CSF) are increasingly used in clinical practice, little is known of their endogenous production, especially in myeloproliferative disorders such as chronic myelogenous leukemia (CML). METHODS: In order to define serum levels of GM-CSF and G-CSF in subjects affected by CML, the sera of 17 patients with CML in chronic phase treated either with hydroxyurea or interferon-alpha were tested by specific enzyme immunoassays. Fifteen age- and sex-matched healthy volunteers were used as normal controls. RESULTS: Eight out of the 17 patients (44%) with CML showed detectable (> 3 pg/mL) serum levels of GM-CSF (range 3.9-55 pg/mL). Detectable levels (> 50 pg/mL) of G-CSF were observed in 9 of these patients (52%) (range 150-2,830 pg/mL). On the contrary, among the normal controls only one had detectable GM-CSF concentrations, and none had detectable G-CSF concentrations. The highest concentrations of both GM-CSF and G-CSF were seen in patients with the highest white blood cell counts, although a linear correlation between the levels of these growth factors and the number of circulating leukocytes was not demonstrated. CONCLUSIONS: Our data indicate that significant amounts of both endogenous GM-CSF and G-CSF are detectable in the serum of a substantial percentage of patients with CML in chronic phase. The pathophysiological meaning of this finding remains to be determined.     

Measurement of endogenous plasma granulocyte colony-stimulating factor in patients with acquired aplastic anemia by a sensitive chemiluminescent immunoassay

Endogenous plasma granulocyte colony-stimulating factor (G-CSF) concentrations were serially measured in 68 patients with acquired aplastic anemia (AA). A very sensitive chemiluminescent immunoassay (CLEIA) was used to measure the plasma G-CSF concentration. The minimum detection limit of this assay (0.5 pg/mL) was sufficient for the determination of G-CSF concentrations in patients and normal subjects. The plasma G-CSF concentrations were significantly higher in 51 AA patients without signs of infection as compared with healthy control subjects. In AA patients with signs of infection, the G-CSF concentrations appeared to increase during the acute phase. There was a significant negative correlation between plasma G-CSF concentrations and absolute neutrophil counts (ANC) in AA patients without signs of infection. Although a decrease in the plasma G-CSF concentration was observed in all patients who achieved self-sustaining hematopoiesis following bone marrow transplantation (BMT) or immunosuppressive (IS) therapy, it was lower in patients undergoing BMT as compared with those receiving IS therapy for any given degree of neutropenia. Plasma G-CSF concentrations were higher in patients responding to IS therapy than in nonresponders. This study demonstrated the negative feedback regulation of G-CSF that plasma G-CSF concentrations may be useful in predicting the clinical response to IS therapy.     

Low Fcgamma receptor III and high granulocyte colony-stimulating factor serum levels correlate with the risk of infection in neutropenia due to Felty's syndrome or systemic lupus erythematosus

PURPOSE: To determine whether serum levels of soluble Fcgamma receptor III and granulocyte colony-stimulating factor (G-CSF) are associated with the risk of infection in patients with neutropenia due to Felty's syndrome or systemic lupus erythematosus. SUBJECTS AND METHODS: Serum levels of G-CSF and soluble Fcgamma receptor III were measured by enzyme-linked immunosorbent assays in 13 patients with neutropenia due to Felty's syndrome, 10 patients with neutropenia due to systemic lupus erythematosus, and 41 controls with normal leukocyte counts (25 with systemic lupus erythematosus, 16 with rheumatoid arthritis). We calculated the area under the receiver operating characteristic (ROC) curves for the absolute neutrophil count, soluble Fcgamma receptor III levels, and G-CSF levels. RESULTS: Nine of the neutropenic patients (7 with Felty's syndrome, 2 with lupus) had one or more infections within 3 months before and after blood samples were obtained. Absolute neutrophil counts were similar in neutropenic patients who did or did not have infections. However, the median level of soluble Fcgamma receptor III (63 vs. 126 arbitrary units, P = 0.005) was significantly lower among patients who developed infections, whereas the median level of G-CSF (90.9 vs. 53.3 pg/mL, P = 0.04) was significantly higher compared with patients without infections. The area under the ROC curve was 0.58 (P = 0.49) for the absolute neutrophil count, 0.84 (P = 0.007) for soluble Fcgamma receptor III levels, and 0.73 (P = 0.03) for G-CSF levels. CONCLUSION: In patients with chronic neutropenia due to rheumatic diseases, low soluble Fcgamma receptor III levels and elevated G-CSF levels are better indicators of the risk of infection than is the neutrophil count.     

Increased serum levels of granulocyte colony-stimulating factor in patients with severe congenital neutropenia.

Severe congenital neutropenia (SCN), also known as Kostmann Syndrome, is characterized by a maturation arrest of myelopoiesis at the level of promyelocytes with absence of neutrophils in bone marrow (BM) and blood. Hypotheses of the pathophysiology of SCN include (1) defective production of granulocyte colony-stimulating factor (G-CSF), and/or (2) defective response to G-CSF. To exclude defective G-CSF production we tested sera from patients with SCN for the presence of G-CSF using Western blot analysis and NFS-60 proliferation assay. Using these assays we were able to detect increased G-CSF serum levels in SCN patients (150 to 910 pg/mL) as compared with normal controls (between undetectable and 100 pg/mL). These results suggest that patients with SCN have no defect in G-CSF production but a defective response of neutrophil precursors to endogenous G-CSF.     

Circulating granulocyte colony-stimulating factor (G-CSF) levels after allogeneic and autologous bone marrow transplantation: endogenous G-CSF production correlates with myeloid engraftment.

Myeloid engraftment after bone marrow transplantation (BMT) is influenced by a number of variables, including cytoreductive chemoradiotherapy, genetic disparity, number of reinfused committed myeloid progenitor cells, healthy microenvironment, and the presence of hematopoietic growth factors. Granulocyte colony-stimulating factor (G-CSF) stimulates proliferation of myeloid progenitor cells and enhances myeloid engraftment after BMT. We investigated the temporal relationship between endogenous G-CSF production and myeloid engraftment in both children and adults after allogeneic (ALLO) and autologous (AUTO) BMT. Circulating endogenous G-CSF levels ranged between 0 and 2552 pg/mL. The correlation coefficient between circulating serum G-CSF levels and the peripheral absolute neutrophil count (ANC) was r = -.875 (P less than .001). The endogenous serum G-CSF level was highest during the first week after BMT, when the ANC was less than or equal to 200/microL (699 +/- 82.3 pg/mL) (P less than .001). Both children and adults demonstrated a similar inverse relationship between circulating G-CSF level and degree of neutropenia. One patient failed to engraft after AUTO BMT and also failed to generate any endogenous G-CSF production. Lastly, once the serum G-CSF level decreased to less than 200 pg/mL, a mean of 6.1 +/- 0.9 days elapsed before the ANC was greater than or equal to 500/microL for 2 consecutive days. This study demonstrates that endogenous G-CSF production is associated with myeloid engraftment in both children and adults after AUTO and ALLO BMT and that the rate of increase and decrease in endogenous G-CSF may be predictive of either failure to engraft or duration of neutropenia.     

The effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) on childhood neutropenias]

The clinical effect of recombinant human granulocyte colony-stimulating factor (rG-CSF), produced by Chinese hamster ovary cells, was studied in 27 patients with childhood neutropenias. The sample consisted of 8 patients with congenital neutropenia (Kostmann type), 9 with neutropenia with miscellaneous causes (5 chronic benign, 2 associated with hypogammaglobulinemia, 1 drug-induced, and 1 hypoplastic type), 3 with cyclic neutropenia, and 7 with severe aplastic anemia. The rG-CSF was given subcutaneously (or in a few cases intravenously) at a dose of 2 micrograms/kg/day for 7 days and 5 micrograms/kg/day for additional 7 to 28 days in cases with poor response. The rG-CSF was effective in 18 of 27 cases (67%). Patients with congenital neutropenia and aplastic anemia responded less frequently and poorly. The mean level of absolute neutrophil counts of 8 congenital neutropenia cases increased from 88/microliters to 2,718/microliters. That of 9 miscellaneous cases changed from 189/microliters to 7,224/microliters at a dose of 2 micrograms/kg/day. In 7 aplastic anemia cases pretreatment level of 220/microliters rose to 851/microliters, usually after increasing the dose up to 5 micrograms/kg/day. The rG-CSF was apparently effective in 3 cases of cyclic neutropenia. In any type of neutropenia, the effect was largely transient; after the discontinuation of rG-CSF, the absolute neutrophil counts tended to decrease to pretreatment levels within 1 to 2 weeks. The G-CSF was well tolerated, and only one case with mild lumbago and another with minimal elevation of transaminases were observed. We conclude that the rG-CSF can be effective for treating various types of childhood neutropenia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection of myelodysplastic syndrome/ acute myeloid leukemia evolving from aplastic anemia in children, treated with recombinant human G-CSF

Backgrounds and Objectives: Recombinant human granulocyte colony-stimulating factor (G-CSF) has clear benefits in patients with severe neutropenia. However, recent reports of myelodysplastic syndrome/acute myeloid leukemia (t-MDS/AML) developing after treatment with immunosuppressants and G-CSF has raised concern over the use of this agent in patients with aplastic anemia. Design and Methods: We undertook a multi-institutional, non-randomized study of 112 children given a diagnosis of aplastic anemia, and then treated with different immunosuppressants with or without G-CSF. In each case, bone marrow specimens were tested at study entry and every 6 months for 3 years to detect t-MDS/AML, defined by stringent morphological and molecular/cytogenetic criteria. Incidence rates were calculated by the person-years statistical method. Results: As of December 2001, all eligible patients had been followed for a median of 3 years, and the G-CSF (+) group had received a median total G-CSF dose of 30,100 micrograms altogether, administered over a median of 4 months. Only one case of MDS developed among the G-CSF (+) patients (n=81), compared with three in the group receiving other agents (n=31). This isolated case was not associated with monosomy 7, the cytogenetic abnormality most often linked to G-CSF treatment. Incidence rates of MDS in the two groups were not significantly different (3.8 vs. 22.4 per 1,000 patient-years at risk, p=0.125). There were no cases of overt AML in either cohort. Interpretation and Conclusions: G-CSF therapy did not increase the risk of t-MDS/AML development in children with aplastic anemia over a median follow-up of 3.7 years     

Plasma/serum levels of flt3 ligand are low in normal individuals and highly elevated in patients with Fanconi anemia and acquired aplastic anemia

The flt3 ligand is a growth factor that stimulates the proliferation of hematopoietic progenitor and stem cells. We established a sensitive enzyme-linked immunosorbent assay (ELISA) to measure the concentration of flt3 ligand in plasma or serum from normal individuals, as well as in patients with hematopoietic disorders. Concentrations of flt3 ligand in plasma or serum from normal individuals were quite low: only 12% (7 of 60) of normal individuals had flt3 ligand levels above 100 pg/mL (the limit of detection). In contrast, 86% (19 of 22) of samples from patients with Fanconi anemia and 100% (eight of eight) of samples from patients with acquired aplastic anemia had plasma or serum levels above 100 pg/mL. Mean plasma or serum concentrations (calculated by assigning a value of 0 pg/mL to any sample reading below the level of detection) were as follows: normal volunteers, 14 pg/mL; patients with Fanconi anemia, 1,331 pg/mL; and patients with acquired aplastic anemia, 460 pg/mL. Concentrations of flt3 ligand in blood are, therefore, specifically elevated to a level that may be physiologically relevant in hematopoietic disorders with a suspected stem cell component. The elevated flt3 ligand concentrations in these individuals may be part of a compensatory hematopoietic response to boost the level of progenitor cells.     

Sustained G-CSF plasma levels following administration of pegfilgrastim fasten neutrophil reconstitution after high-dose chemotherapy and autologous blood stem cell transplantation in patients with multiple myeloma

OBJECTIVE: Pegfilgrastim has shown to decrease the duration of severe neutropenia after conventional chemotherapy, but its use after high-dose chemotherapy and autologous blood stem cell transplantation has not been established yet. Therefore we studied the efficacy and the pharmacokinetic profile of pegfilgrastim in patients with multiple myeloma undergoing high-dose chemotherapy. METHOD: In total, 21 patients received a single subcutaneous injection of 6 mg pegfilgrastim on day +1 after transplantation and pegfilgrastim plasma levels were measured daily by enzyme-linked immunosorbent assay. Clinical outcome was compared with pegfilgrastim levels of 282 plasma samples and data of a historical control group of patients without granulocyte colony-stimulating factor (G-CSF) support. RESULTS: Pegfilgrastim levels showed an inverse correlation (r = -0.68, p < 0.01) with neutrophil counts. Peak levels were reached at day +4 (94 ng/mL; range: 37-205) and were maintained until day +7 (85 ng/mL; range: 35-186). Comparison with the control group without G-CSF support showed that time to neutrophil reconstitution was significantly shorter in the pegfilgrastim group with 10 vs 15 days, respectively (p < 0.001). There was no correlation of pegfilgrastim levels and the duration of neutropenia, although patients with a fivefold increase in neutrophil counts the day after pegfilgrastim administration had a significantly shorter median duration of neutropenia in comparison to patients who were less susceptible to G-CSF stimulation (5 vs 7 days, p < 0.01). CONCLUSION: Neutrophil reconstitution after high-dose chemotherapy could be accelerated by the use of pegfilgrastim in patients with myeloma. Responsiveness of neutrophils to pegfilgrastim before neutropenia was correlated with faster neutrophil reconstitution, whereas G-CSF levels had no impact on neutrophil recovery.     

BAL induces an increase in peripheral blood neutrophils and cytokine levels in healthy volunteers and patients with pneumonia

STUDY OBJECTIVES: To examine the peripheral effects of BAL on the neutrophil counts and cytokine levels in the circulation. DESIGN AND METHODS: WBC counts and plasma cytokines were measured before and 4 h after fiberoptic bronchoscopy (FOB) without further interventions (n = 6), or combined with BAL in normal volunteer subjects (n = 6), and in patients with bacterial pneumonia (n = 4). The bronchus of the right middle lobe was wedged, and three 50-mL aliquots of sterile saline solution was instilled. There was no endotoxin contamination in the saline solution or the fluid obtained through the working channel of bronchoscope. RESULTS: In volunteers, peripheral WBC counts and the number of nonsegmented and segmented neutrophils increased after the BAL procedure (p < 0.05) associated with the increase in plasma concentration (mean +/- SEM) of interleukin (IL)-6 (0.99 +/- 0.32 pg/mL before BAL and 20.38 +/- 13.42 pg/mL after BAL; p < 0.05) and granulocyte colony-stimulating factor (G-CSF; 14.1 +/- 1.7 pg/mL before BAL and 38.5 +/- 9.7 pg/mL after BAL; p < 0.05). The increase in WBC counts and neutrophil counts was positively correlated to the increase in IL-6 (p < 0.05) and the increase in G-CSF (p < 0.05). In patients with pneumonia, IL-6 and G-CSF levels were higher after BAL than in normal volunteer subjects (p < 0.05). There was no increase in plasma concentration of IL-1beta, tumor necrosis factor-alpha, or IL-8 after BAL in normal volunteer subjects or in patients with pneumonia. FOB without BAL did not increase the WBC count, neutrophil count, or plasma cytokine levels. CONCLUSION: The BAL procedure increases the number of WBCs, and segmented and nonsegmented neutrophils in the peripheral circulation as well as circulating IL-6 and G-CSF levels.     

Rapid leukaemic evolution in a cutaneous blastic NK-celllymphoma initially diagnosed as pseudolymphoma

This study was aimed to evaluate the efficacy of G-CSF (Granulocyte colony stimulating factor) administration to 37 patients with neutropenia following intensive combination chemotherapy. The patients were divided into two subgroups including solid tumors given ifosfamide and etoposide combination chemotherapy (IMET subgroup) and acute myeloid leukemia (AML) patients treated with mitoxantrone and cytarabine. Control group consisted of 31 acute myeloid leukemia patients. G-CSF was started on the first day of absolute neutropenia until the absolute neutrophil count was above 1000/mm³ for two consecutive days. G-CSF was found to be effective for early recovery of neutrophil count. Expected response was achieved within 14 days in 91.5% of the courses with a median of fifth day of G-CSF treatment. In conclusion, this study showed the efficacy of G-CSF in early recovery of neutrophil count without any reduction in the incidence of febrile episodes and documented rates of bacterial and fungal infections in patients with acute myeloid leukemia.     

Lithium therapy of children with chronic neutropenia

We treated five children with chronic neutropenia using lithium carbonate and studied the effect in vivo on granulopoiesis. Granulocyte precursors (CFU-C) from blood and marrow, and colonystimulating activity (CSA) from peripheral blood leukocytes, were assayed in a methylcellulose tissue culture system. Three patterns of response to lithium were seen. In patients with aplastic anemia (one acquired and two Fanconi's aplastic anemia) despite increased colony-stimulating activity, CFU-C numbers remained very low and the neutropenia persisted. In a patient with Kostmann neutropenia colony-stimulating activity, and blood and marrow CFU-C numbers increased, but the agranulocytosis was unchanged. An impressive therapeutic effect was seen in one patient with idiopathic neutropenia with low colony-stimulating activity who responded to lithium with an increase in colony-stimulating activity and CFU-C resulting in persisting normal neutrophil counts. Lithium appears useful in treating a select group of neutropenic patients in whom colonystimulating activity production is responsive to lithium, and the granulocytic progenitor compartment is capable of producing mature neutrophils.     

Granulocyte colony-stimulating factor in cerebrospinal fluid from patients with meningitis.

Granulocyte colony-stimulating factor (G-CSF) in the cerebrospinal fluid from patients with meningitis was measured by our modified enzyme-linked immunosorbent assay for G-CSF. The minimal detection level was 20 pg/mL G-CSF. In patients with bacterial meningitis, the G-CSF levels in the cerebrospinal fluid were extremely elevated, showing a mean value of approximately 1,500 pg/mL. On the other hand, G-CSF levels in the cerebrospinal fluid from 67% patients with aseptic meningitis were moderately increased, showing a mean value of about 80 pg/mL, whereas G-CSF levels in 33% samples remained undetectable. The G-CSF levels and neutrophil counts in the cerebrospinal fluid were proven to be related by Spearman's rank correlation coefficient analysis (r = .724). These elevations of G-CSF levels at inflammation sites associated with bacterial meningitis may indicate that G-CSF plays an important role in the combat of bacterial infections.     

Clinical course of non-severe aplastic anemia in adults

The clinical course of non-severe aplastic anemia is variable, and risk factors related to disease progression are not well known. We reviewed clinical and laboratory data of the patients who were diagnosed with non-severe aplastic anemia from 1997 to 2007 at Seoul National University Hospital and analyzed the clinical course and outcomes in these patients. We defined non-severe aplastic anemia as hypocellular marrow with cytopenia in the peripheral blood, which does not meet the criteria for severe aplastic anemia (at least two of the following: ANC < 500/μl, platelet < 20,000/μl or reticulocyte < 20,000/μl). Among a total of 96 patients, 53 (55.2%) were male and the median age was 37.6 years old. As much as 41.7% (40) of the patients were initially asymptomatic. Sixty-two patients who were treated with oxymetholone, ATG/ALG, cyclosporin or other agents after initial diagnosis showed significantly lower levels of initial hemoglobin, red blood cell count and platelet count than those who did not receive any treatment. During the follow-up period, 18 patients progressed to severe aplastic anemia. Their median age was 29.9 years and the median progression time was 18 months. Initial white blood cell count and absolute neutrophil count in the evolution group tended to be lower than in the other group. The patients whose thrombocytopenia did not respond to treatment showed markedly higher frequency of progression to severe aplastic anemia. Treatment itself and responsiveness in reticulocyte and absolute neutrophil count were not correlated with their clinical courses. Sixteen patients showed overall improvement, whereas three patients developed secondary hematologic disease, acute myeloid leukemia, myelodysplastic syndrome and paroxysmal nocturnal hemoglobinuria. Non-severe aplastic anemia has a relatively indolent and mild clinical course. However, 18.8% of the study population progressed to severe disease. White blood cell and absolute neutrophil count at diagnosis and treatment responsiveness of thrombocytopenia were associated with disease progression. Careful monitoring and early management are needed for patients at risk.     

Transformation of severe aplastic anemia into acute myeloblastic leukemia with monosomy 7

 A cytogenetically normal man with severe aplastic anemia was treated with granulocyte colony-stimulating factor (G-CSF), erythropoietin (EPO), cyclosporin A, anti-thymocyte globulin, and interleukin-6 (IL-6), which resulted in a gradual improvement in his neutrophil count and hemoglobin level. After 2 years of the therapy, monosomy 7 was detected during cytogenetic analysis of his bone marrow, which evolved during a period of 5 months into acute myeloblastic leukemia. An in vitro proliferation assay of cytokine responses showed that leukemic blasts were sensitive only to G-CSF, and not to EPO or IL-6. Although allogeneic bone marrow transplantation from an HLA-matched unrelated donor was carried out in the non-remission stage, the patient died of systemic fungal infection on day 25, without any evidence of hematological engraftment. As long-term use of cytokines and immunomosuppressants in patients with severe aplastic anemia may induce or hasten the onset of a malignant transformation, careful attention must be paid to clonal evolution. Due to the poor prognosis of secondary myelodysplasia and leukemia, allogeneic bone marrow transplantation for such patients must be carried out early in the course of the disease. Received: 27 September 1995 / Accepted: 19 December 1995     

Mice lacking granulocyte colony-stimulating factor have chronic neutropenia, granulocyte and macrophage progenitor cell deficiency, and impaired neutrophil mobilization

Mice lacking granulocyte colony-stimulating factor (G-CSF) were generated by targeted disruption of the G-CSF gene in embryonal stem cells. G-CSF-deficient mice (genotype G-CSF-/-) are viable, fertile, and superficially healthy, but have a chronic neutropenia. Peripheral blood neutrophil levels were 20% to 30% of wild-type mice (genotype G- CSF+/+) and mice heterozygous for the null mutation had intermediate neutrophil levels, suggesting a gene-dosage effect. In the marrow of G- CSF-/- mice, granulopoietic precursor cells were reduced by 50% and there were reduced levels of granulocyte, macrophage, and blast progenitor cells. Despite G-CSF deficiency, mature neutrophils were still present in the blood and marrow, indicating that other factors can support neutrophil production in vivo. G-CSF-/- mice had reduced numbers of neutrophils available for rapid mobilization into the circulation by a single dose of G-CSF. G-CSF administration reversed the granulopoietic defect of G-CSF-/- mice. One day of G-CSF administration to G-CSF-/- mice elevated circulating neutrophil levels to normal, and after 4 days of G-CSF administration, G-CSF+/+ and G-CSF- /- marrows were morphologically indistinguishable. G-CSF-/- mice had a markedly impaired ability to control infection with Listeria monocytogenes, with diminished neutrophil and delayed monocyte increases in the blood and reduced infection-driven granulopoiesis. Collectively, these observations indicate that G-CSF is indispensible for maintaining the normal quantitative balance of neutrophil production during "steady-state" granulopoiesis in vivo and also implicate G-CSF in "emergency" granulopoiesis during infections.     

Serum G-CSF levels are not increased in patients with antibody-induced neutropenia unless they are suffering from infectious diseases

By the use of a G-CSF-specific ELISA we determined the serum granulocyte-colony stimulating factor (G-CSF) levels in 63 patients with antibody-induced neutropenia including neonatal immune neutropenia, autoimmune neutropenia, and drug-induced immune neutropenia. In the sera of 20 patients, elevated G-CSF levels of 60-1006 pg/ml (normal <39 pg/ml) were observed. These patients suffered from infectious diseases at the time of blood collection. G-CSF levels normalized after successful antibiotic treatment, indicating that increased G-CSF production in patients with immune neutropenia may be primarily the result of infection and not of neutropenia.     

Therapy for neutropenia in hairy cell leukemia with recombinant human granulocyte colony-stimulating factor

STUDY OBJECTIVE: To determine whether recombinant human granulocyte colony-stimulating factor (G-CSF) is effective in increasing neutrophil counts in patients with hairy cell leukemia and neutropenia. DESIGN: Open label, phase I/II study of G-CSF, given by daily subcutaneous injection for up to 7 weeks. SETTING: Outpatient oncology clinic of a university medical center. PATIENTS: A consecutive sample of four patients with hairy cell leukemia complicated by severe neutropenia. Three patients completed the study; one patient was removed after 2 weeks of therapy. INTERVENTIONS: Granulocyte colony-stimulating factor was given by daily subcutaneous injection. Each patient began therapy with 1 microgram/kg body weight.d; after 1 week the dose was increased to 3 micrograms/kg.d, and 1 week later to 6 micrograms/kg.d. Therapy was continued for 5 to 6 weeks. Patients were taught self-injection, and administered treatment at home. MEASUREMENTS and MAIN RESULTS: In three patients, an increase in absolute neutrophil counts from less than 0.9 X 10(9)/L to greater than 4.0 X 10(9)/L was noted within 2 weeks of beginning G-CSF therapy. In two patients, infections resolved during therapy. One patient developed acute neutrophilic dermatosis (the Sweet syndrome) while receiving 3 micrograms/kg.d of G-CSF, and drug therapy was discontinued. CONCLUSIONS: Granulocyte colony-stimulating factor may increase neutrophil counts within 2 weeks in patients with hairy cell leukemia and neutropenia. This therapy may be a useful adjunct to definitive treatment of hairy cell leukemia with interferon or pentostatin.     

Treatment of myelodysplastic syndromes with recombinant human granulocyte colony-stimulating factor. A phase I-II trial

STUDY OBJECTIVE: To determine the hematopoietic effects and toxicity of recombinant human granulocyte colony-stimulating factor (G-CSF) in patients with myelodysplastic syndromes. DESIGN: The G-CSF was administered by daily subcutaneous injection to outpatients in a phase I-II trial. Dose was escalated every 2 weeks between 0.1 to 3.0 micrograms/kg body weight.d over an 8-week treatment period. SETTING: Outpatient clinical research center at a university hospital. PATIENTS: Twelve consecutive patients with myelodysplastic syndromes: two refractory anemia, seven refractory anemia with excess of blasts, three refractory anemia with excess of blasts in transformation. MEASUREMENTS AND MAIN RESULTS: In 10 of 12 patients, elevations in blood leukocyte counts (2- to 10-fold) and absolute neutrophil counts (5- to 40-fold) were seen over the 8-week treatment period. Five of seven severely neutropenic patients (absolute neutrophil count, less than 0.5 x 10(9)/L) had a rise in count to 1.2 to 16.3 x 10(9)/L. Increased reticulocyte counts occurred in 5 patients, and were associated with decreased transfusion requirements in 2 of 9 erythrocyte transfusion-dependent patients. Treatment with G-CSF enhanced marrow myeloid cell maturation in 9 of 11 evaluable patients. Neutrophil chemotaxis and phagocytosis in vitro were improved or unchanged after treatment in 6 of 8 patients tested. In 11 of 12 patients, there were no substantial changes in platelet, lymphocyte, eosinophil, or monocyte counts. Three responding patients initially had abnormal cytogenetics that persisted after G-CSF therapy, suggesting induced differentiation of the abnormal clone. The therapy was associated with minimal toxicity. None of the patients' conditions converted to acute leukemia during treatment or in short-term follow-up. CONCLUSIONS: Treatment with G-CSF administered by subcutaneous injection is well tolerated and effective for improving the neutropenia, and less commonly the transfusion-dependent anemia, over 6 to 8 weeks in patients with myelodysplastic syndromes.